RT Systems Programing Software Accessibility Review

Posted on June 14, 2013 by The Active Elements Team

By Dave Marthouse N2AAM

June 2013

I would like to bring a few things to the attention of folks who are looking for a speech-friendly no hassle software method of programming amateur gear.

Rt Systems http://www.rtsystems.com produces a line of software programming
packages for a large variety of amateur radios. They produce software packages to program the Kenwood TH-F6A, the Wouxun KG-UV series of hand-helds, Yaesu, Icom, and loads of others.

As a screenreader user naturally I was concerned with accessibility. The software for the TH-F6A can not be used with jfw. I haven’t tested it with WindowEyes so I can’t comment on it’s usability there. The good news is it works flawlessly with NVDA.

The app is arranged like a giant spread sheet. You use your up and down arrows and the tab key to navigate around the settings. There is a convenient standard pull-down menu for settings like cut/paste, copy save, read and write to radio etc.

Another great thing about this package is the system works with all state of the art machines including Windows8. The programming cable has a usb connecter so you don’t have to worry about usb to serial adaptors and compatible drivers and other hassles.

I plugged in the supplied usb cable and the computer recognized it right away. Then it was a matter of just installing and running the software. If you know just a minimum about spread sheets you will have no difficulty with this app. I had the system running within 5 minutes of installation. For me it was so intuitive that I didn’t need to consult the documentation.

The only minor sticking point is if you order the app on cd you must type in a serial number when you install it. Access to a set of working eyeballs is highly recommended for this step. LOL! The serial number is on a label on the envelope in which the cd is shipped. You can also download the software after you purchase it on-line. I’m not sure how the serial number is handled if you use that purchasing method.

The bottom line is the app works great with the TH-F6A and is accessible using NVDA. If their other apps work as well with NVDA this in my opinion is a very good speech-friendly way to program a wide variety of amateur gear.

As far as price you will spend about $25 for the software and slightly less for the cable. You can get the software separately from the cable as some radios use a single cable, (example the Kenwood and Wouxun).

I give the app five stars. I know this sounds like a commercial. I can assure you that I get nothing from Rt Systems. I’m just posting this for those who may be interested and would benefit from the information.

Dave Marthouse N2AAM

Related Downloads

R T Systems Youtube demonstration using the NVDA screen reader

Thoughts on touch screen technology and amateur radio

Posted on June 8, 2013 by The Active Elements Team

I recently wrote the following on an email list for blind radio amateurs. It was in response to concerns about the increasing use of touch screens to replace physical controls. I thought it would be useful to post here, and might help explain why touch screens, even with full talking accessibility, might not be ideal for all radio applications.

If the accessibility has been implemented properly, touch screen technology can be easily used by a blind person, and in the case of the Smartphone, can lead to the use of apps that would never be found with a traditional device. On this basis I certainly wouldn’t dismiss touch screens out of hand.

Saying all that, there is a problem with touch screen technology that I’ve not heard mentioned anywhere else. Basically, you need to be listening ‘fully’ to know what you are doing. On a device with voice feedback and traditional buttons, you can probably get most things done with only cursory attention to the voice, because you remember the sequence of physical operation. Using a touch screen needs you to be listening to the feedback completely at every stage.

On a radio, this is not a useful function. Ideally you will want to make adjustments without any chatter that might distract you from the signal. I touch on this scenario in my review of the Kenwood TS-590, when pressing the button to hear the sub VFO. The frequency is announced by the voice every time you press and release the button. Fortunately, you can turn off the automatic chatter, and it can be seen that Kenwood have given this some careful thought. Too much talk is as bad as not enough!

Turning a silent physical control to adjust say Noise Reduction is likely to be much more comfortable for a blind operator, than one being forced to use a chattering touch screen. It is for this same reason I prefer not to use software, with a talking screen reader, to control a radio in real time. The only audio I ideally want to hear is the incoming signal, anything else can be a distraction <big smile>!

N1MM Accessibility Review

Posted on June 7, 2013 by The Active Elements Team

N1MM audio review and demonstration

By Kelvin Marsh M0AID

June 2013

This is a review of N1MM Logger 13.5. N1MM Logger is a main stream amateur Contest logging program, and despite it’s complexity, it can be satisfactorily used by a blind operator.

To download N1MM please visit the developers
Website at
N1MM.COM

The following Mp3 files take you through the installation, setup, and basic operation of N1MM using a screen reader. In the recordings I use Window-Eyes 8.2 and Windows 7 64 bit Professional.

Related Downloads

1 Installation.MP3

2 Entering personal data.MP3

3 Configuring the radio CAT interface.MP3

4 Configuring the Winkeyer interface.MP3

5 Changing the function keys.MP3

6 Selecting and using a contest log.MP3

7 Monitoring areas on the screen.MP3

8 Editing QSOs.MP3

9 Reviewing the logging screen.MP3

10 Setting up and using a rotator.MP3

11 Tips.MP3

Recent Additions

Posted on May 17, 2013 by The Active Elements Team

Thanks to the recording skills of Ian DJ0HF we have recently added MP3 manuals for both the original and SDA 100 SteppIR antenna controllers.

Tim GI4OPH sent us the RNIB cassettes for the TR-751 and TR851 Manual, and Chris M5AGG converted these to MP3.

The above MP3 audio can be found on the Manuals page, accessed from Recordings.

Rob K6DQ sent us the files he produced for the TM-V71A and E. He converted the complete manual into HTML format and it opens as a fully indexed web page. He also sent us an HTML table of the menu system, and a mike keyboard and front panel description. These are on the Kenwood TM-V71E page under the Related Downloads section.

You can also use the Search field at the top of each page to find items of interest!

Elecraft KX3 Accessibility Review

Posted on May 15, 2013 by The Active Elements Team

Accessibility Evaluation of the Elecraft KX3

By Kelvin Marsh M0AID

May 2013

The KX3 Is the first Elecraft radio I have tried. Several of my amateur friends have been using Elecrafts for several years, and the brand certainly seems to engender a loyal following!

I have had the opportunity to borrow a KX3, serial number 1907, while my friend G4JZL has gone on holiday. Reading comments from others on the Active Elements email group, I count myself very privileged to have been entrusted with such a prized possession!

The KX3 in this evaluation used firmware version 1.1.2, a very early firmware version. The very latest Beta firmware in early May 2013 is 1.4.7, and Rob K6DQ has tried out some of my findings with version 1.4.4. Rob describes the firmware progress as being akin to having a new radio every few weeks, and it is interesting to note the improvements already made to the CW readout in recent upgrades.

I have only spent a few hours with the accessibility documentation, and I feel I only understand the basic operation. Due to the rapid development of the KX3 firmware It is very likely that the findings in this review will have changed again, or I have overlooked something obvious!

The KX3 is an HF radio covering from 160m to 6m. The power output is up to 10 watts from an external power source, and it has an internal battery and an internal auto ATU capable of matching a 20 to 1 SWR. There are many optional extras such as the 100 watt amplifier and the narrower roofing filters, and the microphone is itself an additional option.

While primarily a portable radio, the KX3 has base station receiver performance in several areas. The April 2013 RadCom review by Peter Hart was very favourable, and on paper some of the figures were comparable with the very best.

It is perhaps too easy to categorise the KX3 as a CW only portable radio, but I can confirm it sounds excellent on SSB transmit, and I found during my testing that the noise reduction on SSB reception is superb. Listening with the KX3 to a weak DX station on a noisy frequency, the Noise Reduction excelled at reducing the fatigue of listening to a weak signal through the crackles and hiss of HF.

My initial impressions of the KX3 was that it was a shape and size unlike anything else I have used before. It is about 200mm wide, 100mm deep, and 90mm high including controls. I can best describe it as being in the shape of a house brick, with the controls on the top surface.

The KX3 has a BNC aerial socket on the right side, and power input and sockets for microphone, Morse key, headphones and PC connection on the left side. There are future plans for an additional 2m antenna connection, and you are given the impression the KX3 is very much at the start of the development cycle. As the KX3 is offered as a kit, I speculate that some of the hardware improvements, such as the 2m VHF capabilities, might be offered as a module for existing radios.

I will describe the top panel as though you are looking down on it from above, in a plan view.

There are 6 buttons on the far left, running from top to bottom. These include the up and down band buttons, the direct frequency initiation, and the auto ATU. The bottom button is the zero in the numeric keypad.

6 more buttons run along the bottom of the panel, starting in the bottom left corner next to the zero button, and ending about two thirds of the way along the facia. These buttons control receiver functions such as Pre-Amp, Attenuation, Noise Reduction etc. These buttons toggle settings on and off with a momentary tap, and toggle other settings with a longer press. An abbreviated CW announcement is given for every press. The pitch of the CW changes as commands are switched on and off. These buttons also act as 1 through 6 in the numeric keypad.

Above these buttons are 3 rotary knobs. As well as turning, these knobs can also be momentarily pressed or held. Often a function is entered by pressing a knob, and the adjustment is made by turning the same knob. Again, you are given adequate CW feedback at each stage. These knobs also act as 7 through 9 when used for frequency input.

To change the transmit power, the third knob is held for about half a second. A beep is heard, and adjustment is made by turning the knob. There is CW feedback when you pause turning the knob, and typically you will hear:

4 R 6

Meaning the output power is set at 4.6 watts.

When in SSB mode, the second knob can be used to control band pass filtering. Tapping the knob switches between High and Low cut, and rotating the knob changes the filter width. A longer press puts the filtering back to normal. You are given CW feedback for High, Low and Normal positions.

Above these 3 knobs and virtually in the top centre of the facia is the LCD display.

The main VFO tuning knob is to the right of the third knob described previously, about three quarters of the distance from the left edge, and finally to the right is the Sub Band tuning knob. This smaller tuning knob is also used for RIT and XIT tuning, and for scrolling through the menu.

There are 6 buttons in two columns of three at the top right of the panel. These buttons change the Mode, and control the swapping of frequencies between the Main and Sub VFOs and the Split functions. The bottom two buttons of this block are programmable, and can be assigned to menu options.

Finally, there are a further two buttons at the bottom right for changing tuning step size and for announcing frequency in CW. The bottom right button also accesses the configuration menu when held, And when not used for CW frequency readout is used for switching the VFO B area of the LCD display to show various parameters, such as power supply voltage, battery voltage, current draw temperatures and other non accessible info. It is worth mentioning here that the HamPod reads all of this information, and this is discussed later.

In terms of usability by a blind op, it is very interesting to discover how Elecraft have put considerable thought into accessibility. The radio can be setup to produce CW feedback for almost all of the controls. This means the KX3 is highly accessible if you read CW. The CW announcements are turned on in the menu system, and it would be nice if this was an option assigned to one of the programmable buttons as a default. It would mean a blind customer could purchase the KX3, turn on the announcements independently, and start using it without sighted assistance.

Although the menu system gives no aural feedback at this stage, the accessibility documentation indicates that Elecraft plan to give CW access to the menu system in future firmware upgrades.

I think that one of the most exciting aspects of this KX3 review is the discovery of the accessibility documentation prepared by Elecraft. The document is specifically written for blind operators, and describes the radio controls. You are encouraged to read the full manual for more in depth information, but the accessibility documentation covers the basic operation of each control. One improvement that could be made to the accessibility documentation is to give each control a structured number. For example, I added A-1, A-2, etc to each of the 6 buttons on the left side. The 6 buttons along the bottom edge became B-1, B-2, etc. Without this additional indexing, it is unnecessarily difficult to search the file, to find the purpose of one control. Similarly, by assigning each control an individual reference number, I can search for ‘Split’, and instantly see it is button C2.

There is a copy of the accessibility document at the foot of this page, and I would imagine it will be updated as new features become available. I would therefore encourage you to find the latest copy yourself as it is unlikely I will be able to keep it up-to-date.

Unless you have a HamPod, having just CW feedback available will no doubt limit the radio’s appeal to non CW operators. The CW feedback speed can be slowed to accommodate a beginner, but it can become laborious as the CW speed decreases.

With the early firmware version on the test radio I could not find a method of interrupting the CW readout once it had started. For example, if I used the band up button to move from 40m to 15m, if I pressed the button quickly, I rapidly moved through 30m, 20m, 17m and onto 15m. The 15m frequency was then announced in CW. If I pressed the band up button slowly, I had to listen to the complete 30m frequency in CW, before further button presses worked. I found all announcements were not automatically interrupted by subsequent button presses, and I had to wait for the readout to finish before I could proceed. I was therefore very pleased to learn the lack of readout interruption on frequency changes has been addressed in later firmware releases, and this demonstrates the advantages of the rapid development cycle, and Elecraft’s continued attention to the accessibility issues.

The readout duration may not be a problem if the CW announcement is set to a rapid 35 words per minute, but for slower speeds, the need to wait for the CW readout to complete was occasionally frustrating.

When pressing the band up and down buttons, you will hear in CW something like:

C 1 4 0 1 1

The ‘C’ at the beginning of the announcement shows the Mode is CW.

Note, the Megahertz and Kilohertz are read back, but the Hertz are not. During my evaluation I could not find a way of having the Hertz announced. The button in the bottom right corner reads back the current frequency. You will hear something like:

C 0 1 1

Note, only the Kilohertz are read back.

Direct frequency input is possible, but with the limitation of only the Megahertz and Kilohertz being accepted. As there is no traditional keypad on the KX3, the buttons running along the bottom and the 3 knobs are used for inputting the numbers. This method works, but I found I could not quickly tap in a frequency without waiting for the CW announcement of each previous key press to finish. I understand there is some improvement to the interruption of playing CW readout, but to be totally certain of accurate input it is still prudent to wait until the completion of each number before pressing the next.

In my experience, it is extremely useful for a blind operator to be able to enter an exact frequency. If the person you are in QSO with says they are moving up 750 Hertz, to get away from QRM, it is often easier and quicker to tap in the direct frequency, than to tune with the VFO, and then need to check you have made the correct adjustment by listening to the readout.

I feel the limitation of not being able to read or enter the frequency more precisely than one Kilohertz, is a serious obstacle for a blind operator.

I was pleased to find there was a Dual Watch feature, and both the Main and Sub receiver can be heard in separate ears. The Dual Watch operation is turned on and off from within the menu, and I believe this can be assigned to a Programmable button. There is a 15kHz tuning limit for the sub receiver, in Dual Watch mode, but it is unusual to have a wider spread for DX.

Rob K6DQ has been working on HamPod compatibility, using a KX3 loaned by Elecraft. Rob tells me ‘support for the KX3 is now equal to the K3.’. Rob had to add code for 26 additional menu screens, and the HamPod knows if it is connected to a K3 or a KX3, so it can process queries and commands accordingly. Rob also tells me existing HamPods can be upgraded with new firmware to include the KX3 support!

I would encourage any blind operator to check Rob’s pages at http://www.hampod.com for the latest information.

In summary, the KX3 is very accessible if you read CW, and will no doubt be improved. Congratulations to Elecraft for going the extra mile, and putting considerable effort into accessibility!

Comment 1

From Chris G5VZ, May 2013:

I think it might be useful to readers to also mention the use of the radio with HDSDR.
I started checking this out last weekend and needed to source a couple of leads to
connect the radio up (The interface connectors are a mix of 3.5mm and 2.5mm jacks
with three poles – standard stereo, that is – and four poles.) Having spent an entertaining
time finding suppliers of these odd combinations of plugs and wires I then discovered
that Elecraft part KX3-PCKT is a KX3 connector cable kit with everything you need
to interface the radio to an amplifier, PC, foot-switch PTT and all that sort of
stuff. With these connectors properly sorted, though, I think other software is
opened up – not just the SDR functions using the KX3’s I/Q input and output but also
HRD and the likes. I imagine that’s an accessibility benefit in the grand scheme
of things. And it also demonstrates that Elecraft’s support of the radio is genuinely
100% of everything you need to get it on the air plus their customer service seems
to be faultless.

Comment 2

From Buddy Brannan, KB5ELV – Erie, PA – May 2013

I fully expect things to get even better in regard to the KX3 accessibility. I just love mine! One thing I’ve done, just yesterday in fact, was to set up the programmable function keys to switch between hand key and paddles, and to switch various antenna tuner on/off, AGC on/off, and dual watch on/off in a five-way toggle. If you or any other KX3 users want the macros, let me know and I’m happy to share.

Comment 3

From Chris G5VZ, June 2013:

The menu control of the Morse user interface is essentially through the menu option headed SW Tone. This can be set to none – shown on the display as OFF – when no beeps are generated on any key presses or to ON, in which case button presses are indicated by beep or bee beep and
so on. The other menu settings are CODE and a speed digit-pair; so it’s CODE 10, CODE 15, CODE 20 and so on for feedback at 10 words per minute,
fifteen or twenty. A bit fiddly though. All covered in the original owner’s manual.

If the radio is powered up with the CWT button (Bottom row, button five counting from the left) pressed then the Morse user interface is activated at 20wpm. That is press and hold CWT then press the two power buttons (BAND and ATU TUNE simultaneously) then when the radio powers up release the power buttons first and finally release the CWT button.

This was implemented in firmware MCU 1.26 / DSP 0.99, 10-24-2012 and anything programmed before October last year doesn’t do this. In the current firmware there is a bug and powering up with CWT pressed and Morse UI already enabled can cause the radio to go into MCU Load status. It doesn’t happen every time and, in fact, only happens very
infrequently. This has happened to me once. The way to switch off Morse UI is through the SW Tone menu option.

As far as I know you cannot select or deselect Morse UI using the KX3 Utility Program with the radio connected to a computer.

The current firmware functionality is named “Morse User Interface (Phase 1)” and the documentation suggests that the later phase or phases will include Morse announcements on menu options as well as the button and rotary control operations already implemented.
Elecraft are very receptive to ‘wish list’ emails so anyone with actual experience should
probably get in touch with Wayne at Elecraft if there are specific (And achievable!) ideas for future firmware.

Hope this is useful.
73 Chris G5VZ

HamPod SteppIReader Accessibility Revieww

Posted on March 31, 2013 by The Active Elements Team

Evaluation of the HamPod SteppIR Reader

By Kelvin Marsh M0AID

March 2013

I have been using a 3 element SteppIR antenna since Autumn 2010. It is a large antenna, and requires a rotator and a substantial mast. In other words, it represents a significant investment, both financially and in execution. The advantage of the SteppIR antenna is its ability to automatically adjust the element lengths, giving a perfectly matched aerial system on the majority of HF frequencies. As the antenna itself is outside, the operator will be controlling it by interacting with the SteppIR control box. This will sit on the bench, and in General mode will automatically adjust the antenna as needed. You can read the accessibility evaluation of the SteppIR controller elsewhere on this site.

If the transceiver interface board is fitted, the antenna is automatically adjusted by the radio, and Apart from the Power button, the only button in very regular use is the Direction button. On the original controller, this button cycles through Forward, 180, and Bi-directional modes. As my normal method of working DX Is to Search and Pounce, the ability to have the rotator pointing West, but within seconds have the beam electrically rotate to the East, is a terrific feature of the SteppIR. Within seconds you can check both the Long and Short paths, Whereas it might take you minutes to swing a traditional beam through 180 degrees and back.

The downside to using the Direction button, for a blind operator, is the constant need to check its status! Because the Direction button cycles through 3 positions on the original controller, I found I very easily lost track of my button presses, and constantly needed to remind myself of the direction.

I did this using an audible light probe. This is a pen shaped device that emits a tone when pointed at a light source. My SteppIR controller uses LEDs to show the direction of the Yagi, and I found I was feeling for the slight indentation of the LEDs, and then checking their status, on almost every long distance QSO. As a DX operator I’m listening for signals on the absolute limit, often 10 thousand miles away. If I found a weak signal in the Pacific, it was natural to also check the Long path, and to press the Direction button to rotate the antenna by 180 degrees. The result of all this was that I was using my light probe literally hundreds if not thousands of times over the course of a year!

OK, it’s taken me a page of meanderings to get here, but you can understand why the SteppIReader, http://www.hampod.com, caught my attention. It seemed I could send my SteppIR control box to Rob K6DQ, and he would make it talk!

If you have read my accessibility evaluation of the SteppIR controller, you will know the Setup menu is not accessible. The need to Calibrate, and create or modify the element lengths requires sighted help. Whilst you can live without this access, the SteppIReader gives you spoken feedback, and complete independence.

My SteppIR control box took less than three weeks to travel to Rob K6DQ and back. I don’t think I have been so excited to receive a parcel
for a long time!

The control box functions in exactly the same way as it did before the modification, but is now fully accessible. I think I would have purchased the mod just to
have the directional modes spoken, but of course there is so much more to it.

The SteppIReader comes with a 4 button keypad and speaker unit that plugs into
the rear of the controller. The only visible modification to the SteppIR control box itself is the addition of the port for the new keypad.

The LCD display on the SteppIR control box has two lines of 16 characters. The first button on the SteppIReader keypad reads both lines of the display, plus the antenna direction which is taken by new internal connections to the LED’s.

Button one therefore reads the control box mode, the frequency, and the direction.

Typically, it might say:
‘General Mode, 18.050mHz, 180.’

Button 2 reads the top line of the display, and button 3 reads the bottom line. Button 4 toggles automatic speech on and off.

I have the original SteppIR control box, and in Ham mode the antenna can be adjusted manually. As the band buttons are pressed, the controller’s frequency is now spoken by the SteppIReader. ** I understand the terminology for General and Ham modes has changed in the new SDA 100 controller.

In general mode, the antenna is adjusted automatically if the interface board is fitted. In this scenario, the frequency is now spoken as new bands are selected using the radio, and is again spoken as the antenna adjusts every 50kHz, as you tune through a band. I really like this feature, as it is wonderful to have the SteppIReader unobtrusively telling me what the antenna is doing.

There is a potential to damage the antenna if high power is used while it is adjusting, and it can be very easy to miss the visual indicator, even for sighted users. The SteppIReader handles this by beeping when the antenna elements are moving.

With the introduction of the SDA 100 controller, the little used Options menu has moved to the main Setup menu. This means the Option menu is now displayed on the LCD display, and is spoken by the SteppIReader. The options menu is still accessible using a light probe on the original controller, and I would imagine the inclusion of spoken prompts would have required a lot of complex internal connections for very little benefit.

Undoubtedly, the major achievement of the SteppIReader is the complete access it gives to the Setup menu. The real excitement for a blind operator is to now be able to use the Create/Modify menu. This allows the operator to independently adjust any of the elements, and save the setting. I won’t write pages on the Setup menu, but its use is much more easily explained in the audio demonstration on this page. Also, if you own the original SteppIR controller, the SteppIReader gives you full control over the Calibration and Retraction functions.

Finally, I need to mention the SteppIReader’s own Configurability. The volume of the voice can be raised or lowered by holding buttons 1 and 2, and the configuration menu is entered by holding button 3. Hear you can tailor the voice to your requirements with Volume, Rate, and Tone adjustments, and change a host of parameters. the configuration even allows you to enable or disable speech for various constant indicators on the display, such as the letter M that is shown when the antenna lengths have been modified, or the letter P that is shown when the 6m passive element has been added. Just in this respect, the understanding that there might be a need to suppress unnecessary repetitions on the display is outstanding.

In my experience, it is unusual to find a third party accessibility solution for a piece of amateur radio equipment, and almost unheard of to fine one with this level of technical integration. This is a 10 out of 10 product, and is truly breathtaking in its concept and application.

Related Downloads

HamPod SteppIReader MP3 Demonstration
HamPod SteppIReader Text Manual

MFJ 1786 Accessibility Review

Posted on March 14, 2013 by The Active Elements Team

Active Elements – working to improve accessibility for radio amateurs with disabilities

Review of MFJ-1786 Magnetic Loop

By Ian DJ0HF

March 2013

Hi,

my name is Ian, my callsign is DJ0HF/G3ULO and this is a review of the MFJ-1786 Magnetic Loop antenna for the Active-Elements web-site.

The MFJ loop is approximately 1 metre in diameter, made from thick aluminium tubing and the tuning capacitor and motor of the loop are enclosed by a thick black ABS plastic housing which also allows the loop to be bracketed onto a mast and it can be used on any frequency between 10 and 30Mhz.

The coaxial cable from the loop carries both the RF signals and the voltage to drive the motor and tune the loop and connects with the controller unit which is mounted in the shack.

I have owned the loop for a number of years and have it mounted in the loft on a short wooden stub mast, my loft is not very large but I have mounted it as far away from any metal as possible and oriented for maximum radiation in the East/West direction. My loft doesn’t have any metal foil lining in the eves so there is just the heavy concrete roof tiles between it and the outside world.

For those who have never used a loop, they are usually mounted vertically and if you look at the loop rather like a polo mint, then the minimum radiation occurs through the hole which for me is North/South and the maximum radiation off of the ends of the loop (for me East/West) and the radiation pattern has the typical dipole figure eight pattern which I can confirm is the case with the MFJ loop.

The advantages of a magnetic loop are that you get a fairly effective antenna in a very small space (1 meter diameter), the disadvantage is that you have to tune the loop very accurately for the frequency you are working on. Though for reception you can listen plus or minus 100Khz or so on most bands and still hear most signals but for transmitting you do need to get the tuning on the nose for good results.

The tuning is done using the remote controller in the shack which requires a 12 volt power supply, which normally comes with the controller and is for 220V AC. The controller has 7 buttons and a crossed needle SWR meter. There is a power on button and lamp on button to illuminate the meter. There is also a Range High/Low button to set the SWR meter for 300W or 50Watts full scale deflection. The maximum power allowed for the loop is actually 150 Watts. I did once try 300 Watts and the loop was fine but the controller didn’t like it and started to smoke. Normally I use 100 Watts which is no problem.

The other 4 buttons are 2 coarse up/down and 2 fine up/down buttons and there is more than one way to tune the loop but this is how I usually do it.
On receive I depress either the coarse up or down button which locks depressed and the motor starts and begins rotating the butterfly capacitor on the loop. In the receiver I hear a weak interference signal from the motor (typical motor hash) and as the loop approaches resonance the interference gets louder and louder on my receiver normally ending up around S8 to S9 and I then press the coarse up or down button again to release it. I’ve usually then gone just past resonance so I press and hold the fine tune up or down button to go back to the resonant point where the S meter reading is highest and that’s it for receive. On transmit I then send a carrier and just use the fine tune up or down button to reduce the SWR to minimum, usually below 1.2:1 and I’m ready to transmit. Of course if I wander up or down the band or change bands then I need to retune the loop but that’s the price you pay for using a Magnetic loop.

The other way to tune the loop is to transmit say 10 watts or so of carrier through it and depress either the coarse up or down button depending on the direction you want to travel and wait until the controller issues a tone indicating it has found the resonant frequency, it then automatically stops the motor and you just have to press the coarse up or down button again to release it. In reality you may still have to jiggle the fine up and down buttons again to get the minimum SWR. A VI operator would need some sort of audio indication of minimum SWR to be able to tune the loop effectively.
There is an adjustment for the speed at which the motor rotates so you can set it to whatever you are comfortable with. A slow speed will make tuning easier but takes a bit longer. I tend to use a relatively slow speed though too slow and the fine buttons may not start the motor at all so there is a minimum you can realistically use.

But the important thing is how well does it work in practice and my first comment would be surprisingly well. Obviously if you can get up a multi-band 3 Element beam then you are not going to bother with a Magnetic loop antenna but many of us are not that lucky and in this situation the Magnetic loop can be a useful solution.

Here I have an FD4 Windom antenna running down the garden, this is an 80 metre dipole but fed offset (about 1/3rd of the way along it’s length) with a step down Balun to match the 50 ohm coax and has a fairly low SWR on 80, 40, 20 and 10 metres. Though works on the other bands with an ATU. I also have a 10 Metre Dipole in the loft.

The lowest usable frequency with the MFJ-1786 is 10Mhz and on this band it is usually around 2 S points or so down on the FD4 at best which is not surprising. Though as 10Mhz is nearly all CW the 12db drop in signal strengths still allows lots of contacts around Europe and beyond, but obviously I normally use the FD4 on this band.

The loop starts to do much better when you get to 14Mhz on this band the signal strength on the Loop is normally around the same as the FD4 in the East/West direction but a couple of S points down for stations located North or South, showing that the loop has real directivity. Whereas the FD4 being really an 80 metre dipole has lots of lobes and becomes almost omni-directional on all the HF bands from 20 Metres up.

In the direction of the loop East/West signals are rarely much down on the FD4 and sometimes up to 3db stronger on the loop. This applies to most signals around Europe and also most of the USA, though I notice that the loop does less well on the very distant DX such as Japan etc. Indicating that the radiation angle of the loop is not really low enough for this DX. I had thought about trying to tilt the loop to lower the angle of radiation but have never got around to trying it. I’ve worked many W/K stations on 20 Metre SSB with the loop.

On 15 metres my best DX is VK and again the loop works as well or better than the FD4 on this band in the East/West direction. On 10 metres it is the same though the 10 metre Dipole usually out performs the loop by 3 to 6db.

Commercial loops are not cheap and the MFJ-1786 is no exception but it really can allow you to put out a reasonable signal on 10 to 30Mhz from a very small space indeed. If you mount it somewhere where it can be touched then be very, very careful indeed as there are thousands of volts generated on the loop which can result in very nasty RF burns even on quite low power. If you really want to get the maximum out of the loop then being able to rotate it through 90 degrees is the way to go and you can either peak the signals in a particular direction or null out signals you don’t want to hear. I’ll get around to doing it one day.

Would I buy the MFJ-1786 loop again if I was looking for a compact HF antenna, the answer for me is a most definite ‘yes’. Just don’t expect it to compete with Kelvin’s (M0AID) SteppIR.

Related Downloads

None

SteppIR Antenna Controller Accessibility Review

Posted on March 14, 2013 by The Active Elements Team

Active Elements – working to improve accessibility for radio amateurs with disabilities

Accessibility Evaluation of SteppIR Antenna Controller.
href=”https://kelvinsite.files.wordpress.com/2013/03/steppir-control-box-photo-for-review.jpg”> picture of steppir control box

By Kelvin Marsh M0AID

March 2013

In Summer 2010 I was looking to replace my 3 element 3 band HF Yagi, and I wanted the new beam to work on as many HF bands as possible. The SteppIR antennas were very attractive as they mechanically adjust the length of the elements, giving a good match on the chosen band. I wanted the 3 element SteppIR, with the 30m and 40m option. This would give me coverage from 6m to 40m. The elements are adjusted by moving a metal tape inside a hollow fibreglass tube, and the lengths are measured accurately with the use of stepper motors. I felt the antenna would be ideal, provided I could operate it without sight! After a lot of research, and a long chat with Tim GI4OPH, I was reassured, and I went ahead and bought the SteppIR.

In 2010 SteppIR were selling their antennas with the original control box, and this has now been replaced with the SDA 100. I am basing this evaluation on the original controller, but the new SDA 100 controller has similar accessibility issues, albeit with some noticeable changes. Although I have not used the SDA 100, I have read the manual, and feel able to add a few comments.

The original control box has an LCD display top left, and below the display are a row of square buttons for band selection. To the right of the display is the Direction button, and below this the Up and Down buttons. At the top right is the Power button, and below this the Mode and Select buttons. My controller has 6 band buttons and I understand this will vary depending on the configuration of the SteppIR you purchase. ** The SDA 100 controller has up and down buttons for band changes, but does not have dedicated buttons for each band. Please listen to the MP3 recording for a description of the SDA 100 control box layout.

In its basic configuration, the control box is used manually to select the element lengths for the operating band. The Up and Down buttons will move the elements by 50kHz for fine adjustment. ** Adjustment can be finer on the SDA 100.

In reality, it is slightly more complicated than this, as some of the band buttons cover two bands. For example, on my controller, the first button is used for both the 30m and 40m bands, and the sixth button is used for the 10m and 6m bands.

The 4 remaining dedicated band buttons can be used to cycle through preset points within the band. For example, a press of the 15m button can adjust the antenna for 21.050mHz, the next press moves to 21.200mHz, and a further press moves to 21.350mHz. To complicate things further, if a press of the 15m button took you to 21.200mHz, and you then moved to another band, the frequency would again be 21.200mHz when you next press the 15m button. This behaviour can be extremely useful, but because you do not always returned to the same known point, for example 21.050mHz, using this system without sight requires a good memory and a lot of discipline, mainly because you might not use 15m again for several weeks, and might easily forget it was last on 21.200mHz. If you use this manual approach for adjusting the elements, one solution is to use an accessible SWR meter to determine when the SteppIR is resonant. Tim GI4OPH explains his own ingenious approaches in the Comments following this evaluation.

Saying all this, you will imagine my appreciation when I discovered the control box can be fitted with a transceiver interface board! This is an optional extra, and the interface allows your SteppIR antenna to be driven by your radio. As you switch to a band, the SteppIR automatically adjusts. As you tune through a band on the radio, the antenna automatically adjusts every 50kHz. This means there is no need to ever press the band buttons! If you accidentally press a Band button or the Up and Down buttons, the antenna will attempt to change length, but will then immediately return to the correct setting as the radio is polled. This is how I use the SteppIR controller, and the transceiver interface removes any concerns over frequency adjustment.

There are however several other features on the SteppIR control that either cannot be used at all, or require other strategies. One of the most useful features of the SteppIR beams is the ability to electrically rotate the antenna by 180 degrees, in just a few seconds. The Direction button allows you to select forward, 180, and bi-directional modes. The same button is used to cycle through the three directions, and the status is indicated by two small LEDs. The LEDs are slightly recessed and can be located and interrogated with an audible light probe. ** The SDA 100 controller now has three buttons for selecting the direction. “Norm” for normal forward direction, “180” for reverse direction, and “BI (3/4)” for Bi-directional when controlling a Yagi antenna or three quarter wavelength mode when controlling a vertical.

The Options menu is the place you perform one off setup, such as telling the control box you have the 30m/40m kit, and the extra passive element for 6m. The status of these options can also be determined using an audible light probe. The Options menu is accessed by holding the Mode button for three seconds. ** Access to the Options menu on the new SDA 100 controller has been integrated into the main Setup menu.

Undoubtedly the area with the least accessibility is the Setup menu. Here you can Test the motors, return to factory defaults, select the make of radio, Create and Modify antenna lengths, and Calibrate and Retract elements. Whilst it is possible to memorise the key strokes for some of these functions, the antenna customisation options available in the Create Modify menu are not accessible.

It is likely you will occasionally want to Calibrate the antenna. If you have a power cut when the SteppIR is adjusting, you may find a calibration is required to get back to the correct element lengths. Also, you may more frequently want to retract the elements if there is an electrical storm, or the system is not to be used for a while. Fortunately, I found I could program one of my band buttons to memorise the retracted position, and so just one button press would achieve this without the need to enter the Setup menu. ** The SDA 100 controller has a dedicated button to Retract the elements.

The SteppIR antenna can be damaged if more than 200 watts is transmitted while the antenna is moving. There is a visual indication on the display for element tuning, but no audio cue. There can be some electrical noise on the receiver itself when elements are moving, and Tim GI4OPH describes how this can be useful in the Comments below.

There are a couple of options available to add reliable aural feedback for element movement. These include the SteppIR Tuning Relay Unit from N8LP, and the HamPod SteppIReader from K6DQ. Both of these units are soon to be evaluated on the Active Elements site. ** An additional tuning relay board can be fitted to the SDA 100, and this will prevent RF damage, by interrupting the amplifier’s PTT circuit when the elements are moving.

In theory, you do not need to use an ATU with this antenna. As the antenna can be adjusted for every frequency, you should always have a perfect match. If required, it is very easy to make small adjustments to element lengths and get a low SWR, but you will of course need an accessible SWR meter to check the resonance.

In summary, The SteppIR antenna works automatically if a transceiver interface board is fitted, but there is no accessibility to the Setup menu. The antenna can be used manually with the aid of an aural SWR meter, but the interface board makes adjustment automatic. For complete spoken accessibility, please read the shortly to be published evaluation of the HamPod SteppIReader from K6DQ.

Comments

From Tim GI4OPH:
I also have the rig interface capability, however as I tend to do a fair bit of hopping around from band to band, I prefer to adjust the Steppr manually when I need it to be resonant.
Regarding the status of the 30/40M selection button, one can normally tell by comparing the loudness of received signals, and indeed even by the general noise level, on which band the antenna is currently resonant.
If in any doubt, one dit at low power is enough to trigger an audible warning from my P2000 swr/power meter. Again I use the P2000 meter as an indicator to ascertain which segment is
selected on those bands with multiple frequency ranges. When the tapes are moving, the motors seem to produce some electrical noise, which is picked up by the receiver. This has been a source of some complaint on the Steppir reflector, however I personally find it advantageous, in that whenever the hash is present it informs me the antenna is tuning.
I suppose some of these methods are a little unorthodox, but it works for me smile!

Related Downloads

SteppIR OriginalControl Box MP3 Manual
SteppIR SDA 100 Control Box MP3 Manual

Kenwood TS-570 Accessibility Review

Posted on March 1, 2013 by The Active Elements Team

Accessibility Evaluation of the Kenwood TS570D HF Transceiver by Phil 2E0OCD

This review is being written in February 2013. At this time, I have been using the TS570D for over a year. I am not a power user, but I’ve used it enough in every-day operation to form a reasonable opinion of its pros and cons as a rig for blind operators, and it is from this perspective that I shall comment.

My TS570D has been fitted with the optional VS3 voice chip. This chip has been superseded in more modern Kenwood models (such as the TS590) by the newer VGS1 chip. The VGS1 generally provides far superior speech access to visual information than the VS3 does. Nevertheless, the tactile nature of this rig’s controls, combined with auditory feedback in the form of bleeps and the spoken information provided by the VS3, mean that the TS570D can largely be operated by a blind op without too much difficulty. Having said this, some initial assistance in setting up the rig would be helpful, and may be invaluable if troubleshooting certain problems.

This review is organised around a description of the rig’s main controls. In the course of describing its controls, I shall also explain how a blind op might best operate the rig, and describe the auditory and spoken feedback which is provided during operation.

Here are my observations in more detail.

The rig is fairly chunky, measuring approximately 273mm back to front (excluding the additional depth of front controls and rear sockets), 285mm side to side, and 105mm top to bottom. The rig has a flip out metal stand which runs across the width of the rig, just underneath and slightly back from the front edge. This helps to slightly elevate the front of the rig and place its controls at a more ergonomic angle.

All the controls on this rig are on the front panel. The controls comprise a combination of tactile rubber buttons of different shapes and sizes, and plastic rotary dials. The controls are arranged into different zones, or groups. Although there are a lot of buttons and dials on this rig, they are sensibly organised and are relatively straight forward to distinguish by touch.

Towards the top left corner of the front panel is a cluster of eight buttons in two columns of four buttons.

The top left most of these is a small round PF (programmable function) button. This can be programmed to perform one of a range of functions. I have programmed this button on my rig to speak the RX signal strength via the VS3 voice chip. (This is achieved by changing menu 41 from a value of 51 to 52.) The remaining seven buttons in this cluster are all rectangular in shape. The first of these is the power button. This is located immediately to the right of the small round PF button, and it has a series of raised dots along its surface which make it easy to find.

The remaining six buttons in this cluster are as follows: buttons to activate VOX and send/receive, buttons to activate attenuation, pre-amp and processor, and a button to activate and tune the internal ATU. There is bleep feedback when these six functions are toggled on and off, the pitch of which is slightly higher when the relevant function is activated and slightly lower when it is deactivated. However, this difference in pitch is quite slight and so may be hard to detect reliably.

The ATU button is the one located at the bottom right of the group of eight buttons. Pressing the ATU button in and then quickly releasing it will toggle between turning the ATU on and off. You will want the ATU on unless you are intending to use an external ATU, in which case you will want it off; you should be able to tell whether it is on or off by the pitch of the bleep made when the button is pressed. With the ATU on, pressing and holding the ATU button in for a second or so will cause the internal ATU to look for a match. Whilst doing so, the ATU provides good auditory feedback through the sound made by the latching of the relays. If a match is found, there is a single beep. If a match is not made, then a longer sequence of CW characters is played. I do not know CW, but I understand from other blind ops that the CW spells out “SWR”. In any case, even if you do not know CW, the sequence of bleeps produced when no match is found is noticeably longer than the bleep produced when it makes a match.

Immediately to the right of this group of eight buttons, and stretching most of the way along the top of the control panel, is a smooth plastic area. This is the LCD display.

Below this group of eight buttons is a 6mm headphone socket, and below this is a standard Kenwood mic socket.

To the right of these two sockets, and below the LCD display, is the numeric key pad made up of twelve round rubber buttons. These have a slightly convex shape. They are organised like a telephone key pad in three columns of four, with the 1 key in the top left, and the 0 key bottom middle. There are four small raised dots on the 5 key making this easy to locate. The bottom left button is Clear, and the bottom right button is the Enter key.

Direct frequency input is very easy: simply press the enter key, enter the desired frequency (omitting the decimal point), and then press enter again. All key entries are spoken, including “enter” when the Enter key is pressed. The new frequency is also spoken after the second press of the Enter key. Pressing the Enter key twice in succession will cause the VS3 chip to speak the current frequency, which is very handy.

Most of the buttons in the numeric key pad perform secondary functions which are activated if they are selected without the Enter key having been pressed first. For example: the 4 key toggles the TX and RX between Antenna 1 and Antenna 2 sockets; the 6 key modifies the operation of the VFO control so that one rotation of the VFO is either 1kHz or 10kHz; and the 7 key toggles the Noise Blanker on and off. Unfortunately, the VS3 chip does not speak the status of these functions, and whilst these keys do issue a bleep when pressed, there is no difference in the pitch of the tone of the bleep to indicate whether a function is in one state or another, so it may not always be easy for a blind operator to determine this. However, with some trial and error, and use of lateral thinking, this can often be overcome. For instance, it will be obvious when toggling between Antenna 1 and 2 which you are on if you only have one antenna connected, or if you have two, if you disconnect one of them. Using frequency read out by pressing Enter twice will tell you whether your VFO is moving in 1kHz or 10kHz steps if you check the frequency before and after a single rotation of the VFO tuning dial. These days, One can even use on-line software defined radios accessed through websites to listen to one’s transmissions to try and determine the setting of other TX related functions.

Moving on, there is a further column of four round buttons to the right of the numeric buttons. These are smaller in size than the numeric buttons, but also have a convex shape. They are the transmit functions which are used in conjunction with the Multi Channel selector dial found towards the bottom right of the rig. From top to bottom, these buttons are: Mic, to set the microphone gain; Power, to set the TX power; Key, to set the internal keyer speed; and Delay, to adjust the delay between TX and RX when VOX is activated. These buttons produce a high tone when activated and a low tone when deactivated.

So, for example, to adjust the TX power, you press the second button down once, then use the Multi Channel selector knob to set the desired power level, then press the Power button again to store the change. The Power button produces a high pitch bleep when the power setting function is activated, and it issues a lower pitch bleep when storing / deactivating the function. The difference in pitch is significant and so will be easy for most people to detect. Unfortunately, the VS3 does not voice the power level (nor any of the other values which can be altered with these four buttons such as the microphone gain level). Nevertheless, it is possible to set power accurately, since the lowest power setting in the range is 5 Watts, the highest level in the range is 100 Watts, and the incremental change is always 5 Watts. So, to set power to 50 Watts, press the Power button once and listen for the high pitched bleep. Then turn the multi channel selector anti-clockwise at least 20 clicks. This brings the power level down to the minimum of 5 Watts. Then turn the Multi Channel selector nine clicks clockwise, which increases the power to 50 Watts. Finally, press the Power button again and listen for the low pitch bleep to confirm that the new power setting has been saved.

The main control to the right of this column of four buttons, is a large VFO tuning dial. It is easy to grip as it has a ridged and rubberised outer surface. On the front face of the VFO tuning dial, there is also a finger indentation. A torque switch is located at six o’clock directly underneath the tuning dial which, when slid to the left provides a light touch movement to the dial. When slit to the right, it provides greater friction in the movement of the VFO dial making it easier to move the VFO in very small increments. I like to have the VFO set to tune by 10 kHz per rotation, but this is adjustable as already indicated by pressing the 6 key which will reduce it to 1 kHz per rotation.

To the left of the VFO tuning dial and hugging the curve are a further three round buttons. These are slightly larger than the numeric buttons, but have a concave shape. These are the mode selectors, and from top to bottom they are: LSB/USB selector; CW/FSK selector; and FM/AM selector. When pressed, the VS3 chip announces the selected function in CW bleeps. This is not very helpful if, like me, you don’t know CW. However, I have learned to recognise the difference between LSB and USB because the CW bleeps for LSB are noticeably longer than the CW for USB (note that both “LSB” and “longer” start with the letter l, which is how I recall it).

Below these three buttons and still to the left of the VFO tuning dial are two very small round buttons (though I understand that on some versions of the TS570D these may be rectangular in shape). When pressed, they bleep, but there is no difference in the pitch to indicate what state they are in. This should not present any difficulties though, as we will see.

The right hand of these two buttons is the 1MHz / Amateur Band mode button. This button toggles the function of the Down and Up buttons between 1MHz and Amateur Band modes – I shall mention this again later.

The left hand of these two buttons is the Menu button. When pressed, the Menu button toggles the menu system on and off. Blind ops considering the TS570D will be pleased to know that the menu system is accessible via spoken prompts from the VS3 voice chip.

To activate the menu system, press the Menu button once. There will be a single bleep and the VS3 chip will announce the menu number, eg, “menu eleven”, and the state of the setting associated with that menu, eg, “on” or “off”. Once the menu system is activated, you use the Multi Channel selector dial to move up and down through the different menus, and each menu is announced by reference to its number. This means that one needs a separate list detailing what each of the numbered menus are in order to make sense of the spoken information. In order to change the setting associated with any given menu, one uses the Down and Up buttons, either on the rig itself, or on the supplied Kenwood microphone. I will discuss the Down and Up buttons on the rig shortly, but on the microphone, they are located on its top surface. The options within a menu do not wrap, so when the last option is reached at the start or end of a menu, further presses of the relevant Down or Up buttons will only elicit a bleep. Each time a menu setting is changed in response to a press of the Down / Up button, the new setting is announced, eg “on” or “off”. Again, one must refer to an external list detailing what the various settings associated with each menu are in order to make sense of this information. Once all changes are made, press the Menu button again, a short bleep is heard and the menu system is deactivated.

Thankfully, a list describing the numbered menus and their settings is provided in the manual, a recording of which is available on the Active Elements and RAIBC websites.

Moving to the right of the VFO tuning dial, there are four further groups of buttons. With the exception of the first and last of these, these are generally used for more advanced operation such as working split frequencies, and, not being a power user, I am less familiar with their operation. So my tour of this part of the rig will be less detailed.

The first is a row of four round, convex shaped buttons, located immediately below the LCD display. Working from left to right, these are as follows: the Down button; the Up button; the Quick Memory Recall button; and the Quick Memory In button.

The Down and Up buttons have a minus and plus sign, respectively, inscribed into their surface. Someone with sensitive touch may be able to make this out. These buttons perform three functions. As already seen, when the menu system is activated, they move down and up through the available settings within the selected menu. Otherwise, there other two functions involve moving the frequency of the currently active VFO: when the rig is in 1MHz mode, they move the frequency by exactly 1MHz; when Amateur Band mode is active, they move the frequency from one amateur band to the next.

The Quick Memory buttons provide a quick way of writing, and then recalling, operating settings into quick memory. There are five quick memory positions. Each time new settings are added to quick memory, the oldest entry drops out of memory and the remaining four entries are shuffled along one place to make way for the new entry, which is added into the number 1 memory position. Data that can be entered into and recalled from Quick Memory includes frequency and mode, as well as other settings. To add a frequency and its associated settings into quick memory, simply press the Quick Memory In button. This button has a tactile dot on its surface. It will bleep to confirm. To recall a frequency and its associated settings from quick memory, press Quick Memory Recall. There will be a bleep, and the VS3 will speak the number of the currently selected memory position, followed by the frequency stored there (it will not speak any of the other settings such as mode). Use the Multi Channel selector knob to click up an down through the five available quick memories. As you do this, the VS3 will speak the memory position and the frequency stored there, and the VFO will jump to that frequency so that the RX can be heard. At this point, a user has two choices. You can either exit quick memory and return to your previous frequency and settings by pressing Quick Memory Recall again. Alternatively, you can choose to exit quick memory and return to normal operation using the settings stored in the selected quick memory position. To do the latter, you need to press the N>VFO button (discussed below) instead of the Quick Memory Recall button. Pressing the N>VFO button causes the contents of the selected quick memory to be copied to the VFO and puts you there whilst also exiting quick memory. In either case, there will be a bleep to confirm.

The next group of buttons is below the row containing the Down/Up and Quick Memory buttons. This group is arranged in two rows of four round buttons. The buttons themselves are slightly larger, and are concave in shape. These buttons largely relate to split operation, which is not an area I have explored in any detail. I shall therefore skip over this section. However, I understand from other blind ops that it is possible to operate this rig in split mode, if that is something you are interested in doing.

The next group is a row of three rectangular shaped buttons immediately below the buttons used for split operation. From left to right these are the Scan button; the N>VFO button; and the Memory In button. The N>VFO button is used, as mentioned above, to copy the contents of a quick memory to the VFO.

The last group of buttons is a column of four rectangular shaped buttons immediately to the right of the LCD display. The top button is a Noise Reduction filter which toggles between three settings: off, and two filters referred to as NR1, and NR2. The next button down is a DSP beat cancellation filter which toggles between on and off. It is usually obvious from the RX audio whether these filters are activated. The next button down activates the CW zero beat function. The bottom button enables the RX bandwidth to be changed if an optional filter chip is installed, which it is not in my rig.

The remaining five controls on this rig are smallish plastic rotary control dials which are all easy to locate and use. The first two are located below the column of four buttons which I have just mentioned. The top one is the RIT / XIT dial which is used for split operation. The bottom dial, which is located at the bottom of the front panel, is the Multi Channel selector dial. This clicks as it turns. This makes the selection of frequency (when in VFO mode), menus (when the menu system is activated), and quick memories (when Quick Memory mode is activated) straight forward. Using menus 4 and 5 in the menu system, the Multi Channel dial can be set so that, when changing frequency in VFO mode, it does so in steps of 1kHz, and to the round frequency, for every click of the dial; this is a very useful setting to bear in mind.

At the extreme right hand edge of the control panel are three further dials which effect the RX audio. They are all designed with an inner and an outer dial which move independently of each other. The top dial is a DSP sloping pass band used to cut out high / low frequency noise. The middle dial is the RF gain and the audio volume. The bottom dial is the squelch, and the IF band pass control which enables you to slightly adjust the RX band pass higher or lower when interference is present. These are all perfectly usable by a blind op as their effect is obvious from the RX audio.

With the exception of the headphone and microphone sockets, all other sockets are located on the rear of the unit. I shall not discuss these as they are amply described in the manual, a recording of which is available on the Active Elements and RAIBC websites.

Three final observations will complete this accessibility evaluation of the TS570D.

First, just to make clear that whilst the VS3 provides spoken access to certain information such as the current frequency, the frequency in quick memories, and the menu system, it does not speak the status of other settings such as mode (although these are indicated using CW tones), filters, and other TX and RX settings.

Secondly, it is worth knowing that the TS570D retains the status of certain settings within each amateur band allocation. Settings being used for each band are stored independently of the settings being used in other bands. The settings that are stored are those which are set when the VFO moves in and out of the band, whether this occurs via direct frequency input, by turning either the VFO tuning or Multi Channel dials, or by moving via the Down and Up buttons. Therefore, if you adjust a setting, such as switching from LSB to AM, this will be retained when you return back to the band. This is the case even if you have powered off the unit and then powered back on. This clearly has advantages, but it can be a little annoying if a setting is changed inadvertently as it may take some time to realise that you have made a change and what that change is. I would suggest, therefore, adopting a fairly strict routine of trying to ensure that all settings are returned to an expected state before switching bands or powering off, in order to avoid unexpected surprises when that band is revisited, or the rig is switched on next time.

Third, whilst it is adequate, the sound quality from the internal speaker is not as good as you may wish, and therefore a separate speaker may be desirable. One of the nice things about the audio on this rig, especially when using an external speaker with an independent volume control, is that you are able to independently control the volume of the RX audio and the information spoken by the VS3 chip. The AF dial on the rig itself can be used to control the RX audio, but this does not change the volume of the VS3 announcements; to do this, you can use the separate volume control on your external speaker. When working with the internal speaker, or on headphones, the VS3 volume is set to a specific level which can not be altered, but I find that it is set to a perfectly acceptable level for my normal hearing.

Related Downloads

TS-570 MP3 Manual
TS-570 Front and rear panel layouts, and Menu system.doc

Yaesu Rotator MP3 Manual

Posted on February 21, 2013 by The Active Elements Team

A recording of the Yaesu G800 G1000 and G2800 rotator handbook has been added to the Manuals section.

Snap Circuits

Posted on February 20, 2013 by The Active Elements Team

Electronics Training by Phil 2E0OCD

February 2013

I recently came across something called Snap Circuits. It’s a product made by Elenco intended to be a fun and educational way of teaching children from 8 to 17 years about electronics. Whilst looking at these, it struck me that they could also be an excellent way of introducing blind amateurs to the subject of electronics, and perhaps, even, in enabling them to complete a
qualifying intermediate project with relatively little support.

Snap Circuits are sold in sets. Each set contains everything you need in order to build a number of circuits. Various sets are available which range in complexity from a set enabling you to build 100 fairly simple circuits, up to a set enabling you to build 750 circuits some of which are fairly complex.

One of the mid range sets is called Snap Circuits SC-300. See this link for product info:
(Please note, depending on your browser, you may need to Copy and Paste this link)
http://www.elenco.com/product/productdetails/snap_circuits®=OTQ=/snap_circuits®_300-in-1_with_computer_interface=MzU3
includes all the parts necessary to build 300 projects. Parts include different coloured LEDs, a photo sensitive cell, fixed resistors of different values, variable resisters, capacitors, lamps, switches, a speaker, microphone, antenna coil, a motor and fan blade, transistors, and various integrated circuit components such as RF and audio amplifiers and sound generators, as well as connectors and jump leads, and of course, a battery holder.

Three of the projects which you can build with the SC-300 set are of particular interest: they include a Morse code generator, and a couple of AM radios.

With the SC500 you get further components and you can also build an FM radio.
No tools or soldering are required for any of the projects. All components snap together. Each kit is supplied with a plastic base onto which projects can be built to make it easier.

The manuals are available for download from the manufacturer’s website in pdf format. The manuals provide an introduction to the Snap Circuits concept, a description of every component included with the kit, and a circuit diagram showing how each project should be constructed together with a short narrative for each project which provides some explanation.

The manuals are fairly accessible with a screen reader insofar as the text goes,
but a screen reader will not provide access to the circuit diagrams themselves.

Learning electronics using Snap Circuits is, of course, not the same as doing so whilst getting your hands dirty in a real workshop, but it could be a bit of fun, and it may be the closest some blind folk with no past electronics experience, or who lack the dedicated support of sighted electronics friends, may ever get to messing about with electronics. And I wonder how different this is from buying a simple off-the-shelf AM radio assembly kit and submitting that for your intermediate project – the process, and end result, is similar in either case.

Snap Circuits kits are sold online. Type “Snap Circuits SC-300” into amazon.co.uk and you will be presented with several kits. If you do this, you may also see another, quite similar product, called Hotwires, which is made by John Adams. It works on the same principle as Snap Circuits, and like Snap Circuits, Hotwires has a good rating. Unfortunately, the manual for Hotwires (which I obtained by calling John Adams head office) is completely inaccessible with a screen reader. This makes it significantly less attractive for a blind user.

Has anyone ever used Snap Circuits (or Hotwires), or have any views on how useful they might be for blind people? I quite fancy having a go myself!

I can only envisage two barriers to a blind person using Snap Circuits independently.
First, one would need a verbal description of each of the circuits in the manuals. This would be fairly easy to do because of the way in which all the connection points are numbered and lettered, and each component is likewise separately identifiable. So a simple description might say something like: snap the battery holder with the positive terminal to E2 and the negative terminal to E4. Then snap the Lamp (L1) to C2 and C3. Etc.

The issue would be to find a reader who was willing and able to record the manual, or at least record a description of the circuit diagrams, as it would be time consuming.

Secondly, one might need some initial help in actually identifying some of the individual components in the set. A battery holder will be readily identifiable, but resisters of different values may be harder to distinguish by touch alone. The components are probably fairly chunky so adhesive braille labels produced using a Dymo gun could probably be used.

Alternatively, tactile markings could be applied to the components using TactiMark or Tulip glass / fabric paint. The polarity of certain components will also need to be indicated as well as the identity of the component. This might be something individuals could get help with from local volunteers.
Any thoughts? Is it a good idea, or a total waste of time? Useful, or not?
Phil

RNIB Recorded Manuals

Posted on February 5, 2013 by The Active Elements Team

We’ve had the great news, the Royal National Institute of Blind People, the RNIB, has given permission for the Active Elements website to host their recordings of Amateur Radio manuals!

Unfortunately, many older recordings were not transcribed from cassette when the RNIB library moved to digital output, and many recordings were made for an individual and not archived.

Amateur radio equipment can be fully serviceable for decades, and can be heard on the air for years. We would ask anyone with recordings of manuals, to please not assume there are copies available elsewhere, and to please contact us. You never know, the fact there is a manual available might just keep someone in the hobby.

HF Inverted L, dipole, and Yagi MP3 Comparison

Posted on January 28, 2013 by The Active Elements Team

One of the most common questions from any amateur new to the HF bands is, what antenna is the best? This is a question that is almost impossible to answer simply, and you can guarantee everyone has a different opinion! By the way, the word ‘antenna’ is interchangeable with ‘aerial’, they both mean the same!

Generally, a large aerial is best for the low end of the HF spectrum, where the wavelength is long, and a much smaller antenna will give you better results on the higher HF frequencies, where the wavelength is shorter.

This is the main reason many amateurs will use more than one antenna, but just as many will use one aerial, either a large wire one giving better results on the low bands, or a small aerial favouring the higher bands. As they are using just one antenna, they accept it will be a compromise and work better on certain bands than others.

If the aerial is resonant on a given frequency, this means it is exactly the right length. This also means the correct impedance is seen by the transmitter, and all of the power generated by the transmitter can be radiated through the antenna. The aerial is said to be a good match.

If you have an aerial that is too long or too short for the given frequency, the aerial will not be resonant, and the transmitter will not be able to transfer full power, the aerial is therefore a poor match.

Fortunately, if the antenna is not too far away from resonance, it can be matched with a matching unit, otherwise known as an Antenna Tuning Unit.

The same is true for received signals, the longer or shorter the antenna is from the resonant length, the poorer the incoming signal will be unless matched. If the aerial is far too long or far too short it may be impossible to match, depending on the matching unit.

If you have a small garden, the most practical solution will be to have just one antenna. Fortunately, one antenna can be made to have multiple band characteristics, and there are a variety of methods employed to give low impedances on multiple bands. The antenna will still be a compromise on certain bands, but not everyone has the space needed for an Antenna Farm!

In my experience, it can be important for a blind operator to use a low impedance antenna. If the aerial has low impedance characteristics on multiple bands, it is likely the operator will be able to match the aerial using the automatic antenna tuning unit built into the radio. This built in antenna tuning unit or ATU will only have a limited range, and only be able to deal with small impedance variations.

The aerial I have used for many years is the trapped dipole. It is a wire antenna and is T shaped in profile. The feeder rises vertically to a T piece at 40 feet high, and the signal is radiated by the wire element, extended each side of the T piece. The overall length of the wire is 106 feet, or 53 feet each side of the T piece. Each leg of the element contains a 40m trap. This means that moving from the T piece, the wire extends for about 33 feet, there is then the trap, and the wire extends approximately a further 20 feet. On the 40m band, the traps isolate the final 20 feet of wire on each side of the dipole, but the whole length of the antenna is used on each of the other bands. Because of the 40m traps, The trapped dipole can be tuned on multiple bands with an internal Antenna Tuning Unit.

My second HF antenna is a Yagi beam. It is a Steppir 3 element Yagi, and the elements mechanically adjust to the correct length for the chosen frequency. The advantage of a beam is its ability to focus the signal in the chosen direction. Whilst most serious DXers (hams wanting to work long distances) will use a beam, they are relatively large, and require a strong mast and a method of turning or rotating the beam. The Steppir is a 3 element beam on 10m to 20m, and a rotary dipole on 30m and 40m.

The subject of this review is the trapped inverted L with very limited grounding. This antenna is more suited to a smaller garden, and gives access to all the HF bands. I literally wince at the prices of some of the small multi-band verticals, but my trapped inverted L was homebrew.

Basically, the trapped inverted L is equivalent to just one leg of my trapped dipole. The length is 53 feet, and the 40m trap is about 33 feet from the feed point, with a further 20 feet of wire to the end.

The feeder, or in this case the coax, runs along the ground to the base of the aerial. Here we mounted a small connections box on a copper ground rod driven into the earth. The coax is split, with the outer screen connected to ground, and the inner conductor bonded to the base of the inverted L wire.

With all antennas, it is important to get it off the ground and as far from surrounding obstructions as possible. In my case we used the bough of a tree to take the wire vertically up by about 20 feet to a pulley, and the remaining 33 feet was pulled horizontally to another support. If you don’t have a tree handy, your pulley could be at the top of a 20 foot pole.

As you can see, you now have an inverted capital letter L. Ideally, the vertical section needs to be at least 20 feet high, but can be as high as you can get it. The higher it is, the less wire will be left to pull horizontally.

So, my inverted L rises vertically 20 feet. Turns at a right angle and runs for about 13 feet to the trap, and then continues horizontally for the remaining 20 feet.

Ideally, the antenna’s grounding would be much more than one ground rod. I have no doubt it can be improved by adding radials, but this review is to see how the basic aerial performs. If you have a small garden, you will not have the space for radials.

In this RX comparison of the trapped inverted L with my other HF aerials, I have made recordings on each of the HF bands. I have marked the start of the inverted L with one beep, the dipole with two beeps, and the Steppir with three.

On 80m you will hear LY1TR in Lithuania, some 1100 miles. Firstly the inverted L followed by the stronger dipole, and then the sequence is repeated. Interestingly, RA4LHD in European Russia calls in at a distance of 1800 miles, and I think he is slightly stronger on the inverted L.

80m LY1TR

On 40m we hear GB4C in England, this is a local contact. Firstly he is quite faint on the inverted L, primarily because the inverted L is vertically polarized, and will favour a longer distance. There is not much to choose between the trapped dipole and the rotary dipole of the Steppir which is broadside to the station.

40m GB4C

Again on 40m we hear Jr1CFP in Japan at a distance of 6000 miles. The inverted L is slightly stronger than the trapped dipole, and the Steppir is the strongest, rotated towards the station.

40m JR1CFP

On 30m we hear SD7W in Sweden on IOTA EU-138 at a distance of 1000 miles. I think the inverted L is slightly stronger than the dipole.

30m SD7W

Again on 30m we hear ZP6CW in Paraguay at 6200 miles. Here, the inverted L is noticeably stronger than the trapped dipole.

30m ZP6CW

On 20m we hear EG5INT on a Spanish IOTA Island with a distance of about 800 miles. Here the inverted L is stronger than the dipole and not far off the beam. We hear the inverted L followed by the trapped dipole, then the Steppir, and finally the inverted L again.

20m EG5INT.

On 17m we hear VK2DX in Australia at about 9500 miles. Following The sequence of three, the inverted L is repeated.

17m VK2DX

On 15m we hear W7VJ in Washington at 4800 miles. The inverted L is receiving almost as clearly as the 3 element at over twice the height. I’m sure the beam would be showing a higher signal strength, but in terms of clarity there is not much to choose between them.

15m W7VJ

Again on 15m we hear W0IZL in Nebraska some 4200 miles.

15m W0IZL

On 12m we hear KU1T in West Virginia some 3700 miles. The inverted L is much stronger than the dipole, but there is noticeably much less noise on the beam.

12m KU1T

On 10m we hear 9A3TY in Croatia at 1000 miles. We hear the three antennas, and then the inverted L again. The inverted L is a workable strength, but with heavy QSB on the final clip.

10m 9A3TY

Again on 10m we hear KH7Y in Hawaii a distance of 7200. Faint on the inverted L, no copy on the dipole.

10m KH7Y

In summary, the trapped inverted L is suitable for a small garden, and is relatively low profile above ground, and has a tiny footprint on the ground. My antenna cost less than the 20m of coax used, and the 40m trap can be bought if you can’t make one. My inverted L was positioned down the garden, and pulled back to the house. I mention this because the horizontal part of the aerial is directly above the coax lying on the ground, and I recall reading somewhere this is desirable. Perhaps the coax acts as a counter poise.

Yaesu G-1000DXC Accessibility Review

Posted on January 18, 2013 by The Active Elements Team

Accessibility evaluation of Yaesu G-1000DXC Rotator

By Kelvin Marsh M0AID

January 2013

During a recent conversation with Rob G0WSC, he told me he was installing a new Yaesu G1000 DXC rotator, and he was looking forward to having computer control. I was immediately interested, because if computer controlled, the rotator would be accessible for a blind user. Rob then mentioned he could adjust the bearing by turning a knob and pressing a button. This all seemed very promising, so Rob brought his rotator control box over to my QTH for me to have a look at.

The Yaesu G1000 DXC is classed as a heavy duty rotator, capable of turning a full size 3 element HF beam. The rotation torque inch / lbs is 950, and the braking torque inch / lbs is 5200 (figures taken from the Vine Communication rotator comparison table).

Looking at the other Yaesu rotors, I would say it is in about the middle of the range. The control box was marked T1AL, and was 200 x 130 x 193mm, and weighs 2.8kg.

It turns out Rob is not actually going to control the rotator from the PC, but from his Yaesu DMU. But, looking at the control box, the rotator appears to be completely accessible as a standalone unit.

My very first rotator was a Kenpro KR600. This rotator had Clockwise and Anticlockwise levers, but the needle was hidden under the glass facia. Fortunately, the axle for the needle protruded through the glass, and we were able to fix a tactile pointer to this central boss, on the outside of the glass. This meant I could hold down either lever and feel the direction of the antenna as the pointer moved.

The G1000 DXC control box is several times better than this. Firstly, it has a tactile knob allowing you to select the bearing. I guess the knob is about an inch in diameter, and has a small bump on the front face. Just turn the bump to the 9 o’clock position, and this will equate to a bearing of 270 degrees, or West. Then, just press the Start button, and the rotator will turn. There is no need to keep your fingers held on either the Clockwise or Anticlockwise buttons!

We then had a look at the glass plate covering the analogue direction pointer. Much to my surprise, the glass plate is designed to be removed, so a more detailed clock face can be fitted! Within seconds, the glass cover was off, and I found the direction pointer to be very tactile. I do not know how robust the needle would be, if the glass cover was permanently removed, and the pointer continually checked.

It is possible to connect the G1000 DXC to a PC for computer control. This requires an additional Yaesu interface box with appropriate cables, but the unit appears to be very expensive. In fact, I found the price to be very slightly more than the rotator itself! The interface model is GS232A and measures 110 x 21 x 138mm, weighing 380gms.

There is also a small knob on the control box to adjust the speed of the rotator. As there is no automatic slow start and slow stop on this rotator, I assume it would be easy to increase the speed manually if you are moving the rotator over a large distance, but decrease the speed again for the stop.

In summary, the Yaesu G1000 DXC seems to be perfectly accessible as a standalone rotator control box. You can either select the heading using the tactile knob and then press the start button, or you can hold either the Clockwise or Anticlockwise buttons and monitor the pointer with your fingers. Connecting the rotator to a computer is possible, but unless I am mistaken, appears to be very expensive.

Finally, if you are looking at the G1000DXC based on this evaluation, please make sure the control box is the same. I can well imagine the rotator could be supplied with another controller. Likewise, other Yaesu rotators in the range.

Comment 1:

By Tim GI4OPH, January 2013

Very interesting. Prior to owning the PST rotor, I used a Yaesu g1000sdx for around 8 years. The controller appears to have been re-designed, as there was no pre-set control on the original unit I had here.

I employed the method of removing the glass facia plate to great effect. The direction pointer was reasonably robust, and providing one wasn’t too heavy handed, it remained in place.

It certainly made for a very accessible method of rotator control, which has been made even better with the addition of the pre-set facility.

Comment2:

By Alan R. Downing KD7GC July 2013
The Yaesu rotors are good, particularly the G1000 and G2800. I turned my 4 element SteppIr with a G1000 for 5 years without problems, and when I replaced the 4 element SteppIr with the much larger DB36, I bought the largest of Yaesu’s line, the G2800. I just took the front cover off and I touch the needle to find out where the rotor is pointing, and I have never moved the needle inadvertently. The G1000 and G2800 both have a button that
can be pressed to turn the rotor from where ever it is to a preset direction. the rotor will automatically go to where you had set it up to go. There is a knob that you can adjust the stop point to, so when the button is pressed, the rotor goes to that set point. I set mine to stop at due North. So, no matter where I am pointing, the rotor always returns to North. I don’t know if the G800 has this feature or not, but just call HRO, and they could tell you.
If you intend to only put up a small yagi, the G800 may well be adequate, but if you are putting up a large yagi with many square feet of wind load, then opt for the G1000, or if the yagi will be huge, better go for the G2800.
Yaesu rotors are not cheap. I don’t remember what the G800 costs, but I think I paid about $800 for the G1000, and over $1500 for the G2800.

Related Downloads

G800DXA G1000DXA and G2800DXA rotator and control box MP3 Manual

Yaesu FT-2000 Accessibility Review

Posted on January 10, 2013 by The Active Elements Team

Accessibility evaluation of Yaesu FT 2000.

I have wanted to evaluate the FT2000 for some time. My good friend Rob G0WSC has been using the FT 2000 for about four years, and whilst Rob is sighted, it became obvious that once initially set up, the Menu seldom needed to be accessed again. In terms of accessibility, the main challenge for a blind operator using the FT 2000 is the lack of a voice synthesiser. Therefore, obtaining the frequency and mode information requires a connection between the radio and a PC. This evaluation is therefore slightly different from the ‘stand alone’ reviews I have conducted previously, as it is indeed possible to use an apparently inaccessible radio with no voice output, if a computer can be operated.

YAESU FT2000

On paper, the FT2000 is an interesting radio. Even for a blind operator, it has certain features that make it worth investigating, even without speech output. I have had the FT2000 here on the bench for a couple of days only, and so this accessibility review can only really be my impressions on the radio, and I would encourage any blind amateur to do more research and check out my very superficial observations.

The radio is physically large, measuring 410 x 135 x 350 mm and weighing 15 kg. It covers 160m to 6m. I evaluated the 100W version, and there is also a 200W model. The version I tested has an internal PSU and the radio is plugged directly into the mains.

For its price point, I believe the FT2000 is currently the most inexpensive radio with separate receivers. The sub receiver must be on the same band as the main receiver, but it is possible to monitor different signals in each ear, using stereo headphones. As I have mentioned in previous evaluations, my usual operating practice is working DX, and this inevitably involves working on Split frequencies. I personally gain great benefit by listening to the DX station transmitting in my left ear, whilst I am looking for a pattern in his RX frequency range, listening with my right ear.

As previously mentioned, this radio will need to be initially setup using the menu system. There is a wealth of information available on the Internet, including e-mail user groups, and many people have published information on their personal Menu setup. It is almost inevitable that a blind operator will need sighted assistance for this initial phase.

I connected the FT2000 to my PC via the RS-232 CAT port, and used my logging program and screen reader to speak the frequency and mode. The physical connection was made using a standard serial cable, connecting to a USB adaptor plugged into the PC. I simply unplugged my usual radio and swapped cables. For some reason, I expected the FT2000 to need a special interface cable, but this was not the case. All this was very straightforward.

As the radio is physically large, my initial impression of the front panel was of an overwhelming mass of controls. There are lots and lots of buttons and knobs, But it doesn’t take long to start understanding the radio’s layout. The radio is turned on by using a button at the top left corner, and the VOX button is conveniently positioned here too. There is a line of buttons on the left hand side positioned horizontally below the display. This row contains the dedicated buttons for Monitor ,Processor, AGC, Noise Blanker, attenuator and filter functions. These buttons are long and thin, and have the same beep regardless of whether you are turning the function on or off. There are differently shaped buttons at the end of the row to select A and B receivers. Below these buttons are two horizontal rows of large knobs of the concentric inner and outer type. These contain RF Power , Mike Gain, VOX Delay, Manual Notch ,and the RF and AF gain for the Main and Sub receivers.

Below and running along the bottom edge, are 8 buttons for transmitting any pre-recorded voice and CW messages.

To the right of the knobs are two further columns of buttons. The first column contains buttons for choosing the mode, and I was pleased to find individual buttons for USB and LSB selection. To the right again is another column of buttons containing the Split, and the TXW button, allowing you to quickly hear the Sub receiver signals.

The main VFO tuning dial is to the right of the previously described controls, and approximately in the centre of the front panel. Each revolution of the VFO moves 10khz, but I would imagine this can be changed in the Menu.

To the right of the main VFO are more buttons for controlling the Main and Sub receivers, the main numeric keypad, the Sub receiver VFO, the Clarifier knob, and the filter adjustment knobs.

It soon became obvious, there is literally a button or a knob for every common function. For a blind operator this is terrific. There is seldom a need to enter the Menu system, but there are a lot of controls to remember!

A brief note on the buttons. All of the buttons are hard plastic, and not the rubber type that drag on the finger tips as you slide your fingers around the operating area. The long thin buttons running under the display on the left hand side are very easy to use, but I found some of the other buttons were quite tricky to orientate myself around, because of their unusual shape. These buttons are not flat, but the tops are tilted, and with a slight concave curve. The buttons are closer to the fascia at the top and thicken slightly at the bottom. In the case of the numeric keypad, the buttons are quite noticeably concave, with the button being thicker at the top and bottom, and being recessed across the middle. This actually makes tactile manipulation more awkward. As you move your hands over the keypad, instead of feeling a block of 12 flat buttons, instead, you have lots of peaks and troughs to negotiate. Until you get totally familiar with the keypad, it is easy to mistake the space between the buttons, as a button itself. There was no tactile pip on the 5.

The keypad uses the Triple Stacking method for band changes, meaning, pressing the number three will cycle you through three different stored frequencies on 40m.

Direct keypad entry of a frequency was straightforward.

I have very little experience of using Yaesu radios, and this is mainly due to the range generally lacking a voice synthesiser. I was therefore new to some of the concepts on the FT2000. For instance, when you are tuning for 0 beat on a CW signal, the Yaesu will give you a visual indication to show you are on the exact frequency, and fortunately, there is also an audio indication. A button press will produce a 700 Hz tone, allowing you to tune, and match the incoming signal to the generated tone.

A maximum power limit can be set when tuning. This works for both the internal and an external ATU. Limiting the tuning power to 20 watts while keeping the TX power at 100 watts is very useful.

Having established the FT 2000 was relatively easy to use, I wanted to make sure I could easily use the split facility and the sub receiver. With a radio of this complexity there are several ways of being able to work split. Sighted operators may well find they never need to use the split function at all, as the Clarifier itself allows an adjustment over 10 kHz! But, from my own personal experience, I like to be able to put in a definite frequency, so I don’t need to keep checking the voice output.

If you are wearing stereo headphones, in the standard set up, you will hear the main receiver in both years. If you press the TXW button, you will hear the sub receiver in both years. A menu setting allows you to hear both receivers at once, the main receiver in your left ear, and the sub receiver in your right ear. As the menu is inaccessible, I am assured the ‘Dual Watch’ function can be assigned to the programmable CS button. I did not actually try assigning the CS button on this borrowed radio, so this is something to make sure of yourself.

If you want to set the split very rapidly, there is a single button option to set the split to a 5khz high shift. This default can be adjusted. But, I think the most straightforward way of setting the Split frequency at say 3kHz up, is to press A=B, to make the Sub receiver equal the Main. Then press A/B and press the microphone Up button three times, this sets the frequency on the Sub receiver. Then press A/B again to return to the Main, and finally the Split button. You are now ready for Split operation with a shift of three kHz.

A press of the TXW button gives a double beep if Split is on, and the Split frequency was immediately shown on the PC. The signal on the sub receiver is heard.

In summary, the FT2000 can be satisfactorily used by a blind operator, but for independent operation needs to be connected to a PC via CAT. Every common function has a dedicated button or knob, meaning the inaccessible menu is not required in daily use.

Related Downloads

None

MFJ 1026 Accessibility Review

Posted on January 4, 2013 by The Active Elements Team

Accessibility Evaluation of MFJ 1026 Noise cancellation Unit.

By Kelvin Marsh M0AID

January 2013

The MFJ 1026 noise cancelling system, front view with telescopic whip fitted

Recently, there was an interesting thread on the active elements reflector, regarding local electrical noise sources. These days, many radio amateurs live in electrically noisy locations, often with close neighbours in a modern housing estate.

Potentially, these local noise sources can make it very difficult, if not impossible, for radio amateurs to continue in the hobby. Very often, the electrical interference is so bad it literally overwhelms the weak incoming signals amateur radio operators strive to hear.

I was interested to learn that several sighted radio amateurs used noise cancelling units. Several of these units had been around for many years, but had been discontinued. Checking with the various suppliers, I found the MFJ 1026 was the modern equivalent, and was widely available.

Firstly, the unit is quite expensive. I have no doubt the manufacturer has done their very best to keep the costs down, but the MFJ 1026 is a significant investment at around £200 GBP. Therefore, I felt it was imperative to check the MFJ 1026 is accessible for a blind operator.

Reading the Manual, my first concern was how to handle the MFJ 1026 transmit requirements. Usually, the MFJ 1026 is connected between the radio and the antenna. This means it can receive incoming signals directly from the antenna, but has to potentially handle several hundred Watts of outgoing RF power when the operator is transmitting. The MFJ 1026 has some features to switch it to automatic bypass, but the Manual is at pains to point out, this method is not fool proof and is not recommended. It is suggested the MFJ 1026 is also connected to the radios PTT circuitry, and is thus switched to bypass, when RF power is applied. This means an additional cable must be fitted, and the specification will depend on the type of radio being used. The additional PTT control line may need to be added to the order, as fabricating the necessary cable could be difficult for an amateur with low vision.

Fortunately, my own radio gives access to incoming signals via coaxial links at the rear. I was able to use the appropriate connection and route the RX signal through the MFJ 1026, avoiding placing the unit in the path of out-going RF.

The MFJ 1026 works by receiving signals on two separate antennas. The noise is brought in by the auxiliary antenna and this is used to cancel the noise on the main antenna. The tricky part of the operation for a blind operator, is to balance the noise signal on both antennas. Usually, a sighted operator will use the radios signal strength meter, but I found it was easier for me to match the balance by ear. I found the best method was to turn the main antenna gain to maximum, so you hear the incoming signal and noise at full strength. I then made a mental note of the noise volume, and turned the main antenna gain completely down. I then brought up the noise on the auxiliary antenna to the same level. The final step involves careful adjustment of the Phase Delay, until the noise is effectively removed.

At this point it is worth mentioning, I had good success using the MFJ 1026 internal whip as the auxiliary antenna. This was very effective at picking up a local noise source . Thus, the main antenna would receive both the radio signal and the noise, whilst the whip antenna would only pick up the noise. The unit can also be used with an external auxiliary antenna, but during my limited testing I found I did not have much success in reducing noises from further afield.

Fortunately, I do not have much interfering electrical noise at my QTH. During the test period, the only local noises I found were a couple of spot frequencies on 15m, when my beam was turned towards the south.

You will now hear a recording of Z81D in South Sudan. The signal is very weak, and without the MFJ 1026, would have been affected by the local noise. Either side of the frequency was in fact clear of noise, but Z81D was just on a bad spot! During the recording, you will hear me calling the station myself, and Z81D making three QSOs. Although these are faint they are without interference, but as he is exchanging signal reports with each station, I briefly turn off the MFJ 1026 and you can hear the rasping interference for a few seconds each time. Whilst these signals are on the limit, you can hear that in this instance, the reception would be virtually impossible without noise cancellation.

Z81D on 15m

Next is a recorded demo of the MFJ 1026 in action. I use the unit to eliminate an electrically generated noise from the 80m band

Audio Demo on 80m

Related Downloads

MFJ 1026 MP3 Manual
MFJ 1026 PDF Front Panel Layout

Baofeng UV-5R Accessibility Review

Posted on December 31, 2012 by The Active Elements Team

Baofeng UV-5R Review

By Ian Spencer DJ0HF/G3ULO

December 2012

This is a review of the Baofeng UV-5R dual band 2 metre/70 Centimetre hand-held transceiver. I suppose I should start by saying what motivated me to buy one, well it was simply the price. Most dual band Hand-Helds are in the 100 pound plus range and the cheaper Woxoun around 85 pounds or so, and this new Baofeng was only 32 pounds here in Germany including postage and if ordered directly from China I have seen it as cheap as 28 pounds almost a third of the price of the nearest competitor.

And although I’m not a VI operator myself I felt that this Hand-Held might be suitable for someone with a visual impairment as it does have some voice announcement features and so I will try to test this by operating the radio with my eyes closed in the hope of getting some idea of whether it really would be suitable or not.

I didn’t expect much for 30 odd pounds especially these days where a simple desk mike often costs a hundred pounds or more and so when it arrived I was pleasantly surprised. It came in a small square carton and on opening it I was presented with a very neat hand-held which didn’t look in the least bit cheap and certainly seemed externally to be up to the build standard of my other more expensive radios. The box contained the Handy plus a 1800maH Li-ion Battery pack, a belt clip, a wrist strap and an extra earpiece for silent listening and a drop in battery charger, this is nice as you can drop the whole Handy into it for charging and don’t have to remove the battery pack or use a fiddly cable to connect the charger. There was also a rather basic instruction book to round off the contents.

The main case of the handy is black (though other colours are available) and on the top you find the socket for the rubber duck antenna and a volume control which includes the on/off switch and a white bright emitter LED which allows the Handy to be used as a torch and which in practice is surprisingly bright. The antenna socket is a reverse SMA (male) type and so if you want to connect another antenna perhaps with a BNC connector then you will need an adapter, though these are readily available for a few pounds on Ebay.

The front is divided into 3 areas and at the top is an LCD Display and below that is the speaker and to the left of the speaker are two important buttons which I’ll discuss in a minute and a small green LED which lights when a signal is being received. In the bottom third are the 4 rows of 4 buttons for menu functions and entering numeric information. All of the buttons are quite a good size and raised above the surface of the Handy and have a very positive click when pressed, so that once I had familiarised myself with the layout I found no problem locating the ones I wanted and operating them even with my eyes closed. On the right hand side is a flip open cover which reveals two sockets, a 3.5mm and a 2.5mm stereo socket into which you can plug the accessory earpiece or a combined microphone/speaker. These two sockets are also used for the programming cable to connect the Hand-held to a PC for programming.

The Li-ion battery clicks firmly into the back of the transceiver and the belt clip is attached by two screws if it is required.. Rotating the volume control turns it on with a click and a voice announces `Frequency Mode’ and the LCD display lights up in Violet with a welcome message for a couple of seconds.

Page 2 of 4

The unit has two basic modes of operation `Frequency Mode’ where two VFO frequencies are displayed on the screen and you can switch between them with a small blue A/B button. Or `Channel Mode’ which uses the 128 memory channels and is selected by a quick press of the orange coloured VFO/MR button. Both the VFO/MR button and the A/B button are placed well away from the other buttons being in the middle section of the Hand-held to the left of the Speaker. On the left side of the radio are three buttons , at the top an orange button which when pressed selects the FM radio for listening to stations in the 76 to 108Mhz broadcast band or it can be switched to the 65-75Mhz band by a quick press of the band button (to the right and just below the speaker). Pressing the orange button a second time turns the FM radio off. In the middle is a larger `PTT’ button and below that a `Moni’ button which is pressed once turns on the LED torchlight, if pressed a second time the LED blinks as an alarm and if you hold it pressed the squelch is switched off, the LCD display turns blue and you hear the usual loud hiss of an un-squelched VHF FM Receiver.

In `Frequency Mode’ I typed in 145500 on the keypad and each key was announced as I pressed it as `one’, `four’,’five’ etc. I was then listening on 145.500Mhz. I pressed the PTT button and the display turned orange and I had a quick contact with a local amateur. Using the standard 4 Watts, though low power 1 Watt is also available. He said it sounded fine though the modulation sounded a little quiet. This seems to be one of the only weaknesses of the Baofeng, you do need to speak very closely to the microphone, it’s said this deliberate as when the Baofeng is used in a commercial environment (for which is was first designed) then they didn’t want a lot of background noise being transmitted if the environment was noisy. I then punched in a 70cm frequency and repeated the test with no problems at all. Later I tested it on 2M and 70cm Repeaters and it worked fine on both bands. If while transmitting you press the band button then it transmits a 1750Hz tone to open a repeater. Though you can also program CTCSS or DCS tones which are required by a lot of repeaters these days. And there we come to a bit of fly in the ointment for all users and especially if you are a VI user. Programming the Baofeng from the keypad is possible but not particularly easy. There are several videos on `You-Tube’ on how to do it but not really practical for a VI user.

Whether you are visually impaired or not, obtaining the programming cable and free software from Baofeng is a must. This makes programming the 128 Memory channels and setting other features a breeze. Here in Germany I paid around 8 pounds for the programming cable but these seem a little more expensive in the UK. Though they won’t break the bank.

I had no problem programming the Baofeng with the standard software and cable. I could do it on both my Windows 7 Professional and Windows XP Professional computers perfectly. Even though the seller had said in his advert that the cable was only for XP. That said there have been a number of items on the internet saying that people had problems with Windows 7. This seems to be down to the version of the Prolific USB driver that windows 7 loads when you plug in the cable. However I have the latest version on my Windows 7 machine and it worked perfectly, this may not be the case with some versions of the driver and you may need to install a compatible version. The free software from Baofeng works pretty well but it’s not particularly sophisticated. There seem to be a number of different versions of the software and a number of versions of the firmware in the Handy. The older models have Firmware BFB28x, the newer BFB29x and there seem to be some differences. On the website I found a version of the programming software with NEW_OLD in the name which I suspect works with all versions but has a couple of unfortunate features.

When it starts there are lots of question marks on the screen because it starts in `Chinese’ and you have to go to top menu bar and select the second item from the right to switch to English.

Page 3 of 4

Then everything magically appears in English. The only other minor problem with this software version is that in the menu bar it doesn’t have the `OTHER’ option which allows you to change the welcome message on the Handy to for example `Your Call-sign’. I think this is missing because this feature is only available on devices with the newer BFB29x firmware. As mine has the newer firmware I used another version of the software from June of this year with the name UV_5R_VIP which does have the `OTHER’ option in the menu and allowed me to change the Welcome message to `DJ0HF’.

The radio is pre-loaded with a lot of channels and you can select `Read from Radio’ to download them into the program and then delete or modify them as you wish. The only unusual feature is that you don’t enter a repeater offset but instead enter not only the receive frequency but also the transmit. So for example as receive you might enter 145.600Mhz and the program automatically displays the transmit frequency as 145.600 as well and you have to change it to 145.000 to get the 600Khz offset. Unusual but not a big problem. Once you have entered all of the simplex and repeater channels you want then you simply click on `Write to Radio’ to upload the data and that’s it. As I said the Software isn’t very sophisticated and so after it tells you it has finished reading or writing the data you actually have to click `Cancel’ to get back to the main screen rather than it going back to the main screen automatically. Sometimes I noticed that the first time I said Read or Write it gave and error but after clicking it away then the second attempt always worked without problem for me. Very important is to know on which `COMM’ port the Prolific USB cable has been configured. It usually ends up on COMM3 but this many not be true, depending on how many COMM ports your computer already has. Some versions of the software automatically see the correct port and select it others you have to choose the `Communication’ option in the menu and click the required COMM port. If you have the wrong port selected then nothing will happen and you will not be able to read or write anything over the cable to the radio.

There is another software package called `CHIRP’ which can be used to program many different types of radio but it warns that it is experimental with the Baofeng, so I tried it in read mode and it read the data from the radio without any problem but I didn’t try writing anything back to the radio in case I `Bricked’ the radio and made it useless. Anyway I find the Baofeng software easy to use and so don’t have any real reason to use CHIRP.

So if you are a VI user could you use the radio. Well assuming you can get someone to help with the programming of the channels or have a very good screen reader which will work with the software, then I think yes.

In `Frequency Mode’ (which is announced) you only have to punch the frequency and all of the keys will be announced and that’s it. You can work simplex on the channel you punched in very easily. Pressing the VFO/Memory button will announce `Channel Mode’ and each time you press the UP or Down arrow the channel will step up or down one memory channel and the new channel number is announced. So as long as you remember your favourite simplex or local repeater channel numbers then there shouldn’t be any great difficulty in finding the channel you want and using the radio.

This review is already getting very long so I don’t want to go into all of the menu items here in detail (there are 40 of them). You can program any of the facilities from the software or by pressing the `Menu’ button and then a two digit menu number. Pressing `Menu’ again allows you to change the value of the item and in some cases announces the name of the menu item selected. After setting the required value pressing `Menu’ again, announces `Confirmed’ and pressing `Exit’ takes you out of the menus.

Page 4 of 4

If you are in `Channel Mode’ then pressing and holding the scan button, starts the radio scanning through all of the memory channels and the start of the scan is announced so if you are a VI user you know the scan has started. You can stop the scan by simply hitting the `Exit’ button. In the menu’s it’s possible to select to stay on the active channel until the carrier drops and then continue scanning, to stay on the active channel for a few seconds and then if `Exit’ isn’t pressed continue scanning or to exit scanning mode completely once an active channel has been found and remain on that channel.

As I say there are so many menu options that I can’t list them all here but for example you can set the squelch level (though I have never had to alter it). Select different colours for the display for Receive, Transmit etc. Set the step size, for example 12.5Khz or 25Khz etc. Turn on VOX operation if you don’t want to use the PTT. Set dual channel watch which allows two VFO frequencies to be monitored, the radio skipping back and forth between them until one of them becomes active. Or you can do the same with 2 Memory channels. Interesting is that if you are listening to FM Broadcast radio and one of the channels becomes active then the broadcast is muted until the activity on the channel ends and then it switches the broadcast receiver back on again. You can of course set CTCSS tones and interestingly you can set them for both transmit and receive. Normally for a repeater you would only set transmit CTCSS so that when you transmit it includes the tone but on receive you don’t need it. But if you set it for receive too then if you are talking from one baofeng to another in simplex or with a group of radio’s the receiver will only open if it hears the CTCSS tone from the other baofeng and ignore any other transmissions on the frequency. You can program a roger beep and lock the keyboard and lots of other things but I think you get the idea.

So is it an all singing all dancing Handy for the VI user, well most certainly not. But could a VI user operate the normal day to day functions of the radio in simplex or on a repeater (once the channels have been set up) I think the answer would be a most definite `yes’.

Comments

Ian DJ0HF has confirmed the following:
1 The frequency will not be read on demand. The frequency numbers are only spoken when entered.
2 The firmware appears to be very similar to the Wouxun KG-UVD1P, but the menu numbering is slightly different. I’m sorry to say that although the menu’s are very, very similar they do not have the same numbers. So for example on the Wouxon, you press ‘Function’ (which is Menu on the Baofeng) then 4 to go to the power Menu, on the Baofeng it’s Menu then ‘2’ then when you press ‘Menu’ again, like the Wouxon it announces ‘Power’ and you can use either the up or down buttons to cycle between high and low power. Like the Wouxon you can also use the one and zero buttons to set the power but unlike the Wouxon the one sets low power and the zero high power. I have recorded chapter 12 of the manual, describing the menu numbering. It is in the Related Downloads section below.
3 I tried to see if I could insert the Handy into the charger without it fully contacting the charger tabs but I really couldn’t. If I hadn’t inserted it properly I could twist the Handy clockwise and anticlockwise, if I had it fully inserted I couldn’t twist it. 4 The Wouxon review said that the Wouxon only gave about 2 seconds to enter a change after selecting a menu item before exiting the menu and returning to the normal mode. My Baofeng gives you about 8 seconds before it does this.
5 Unlike the Wouxon there is no rotary control on the top for changing frequency/memory channel or menu item. There are just the up and down keys and the numeric keyboard.

Peter MM5PSL comments:
Kelvin, You mentioned the problem of a slack charger on the Wouxun review. The Baofeng has a similar problem. The charger opening for the radio is too big and there’s quite a gap around the sides. The answer is knowing how to insert the radio. Unless by accident, only a sighted person would notice how it slots in. The radio has to be inserted with the back of the radio against the back of the opening and it slots in snugly. If it is too far forward it misses the guides on each side

Related Downloads

Baofeng UV-5R MP3 Tutorial by KA9OPL (opens a new page on Joe’s own site)
Baofeng UV-5R Chapter 12, Menu Numbering MP3
Baofeng UV-5R Tips and Hints for Eyes Free Operation by Buddy Brannan, KB5ELV
Baofeng UV-5R MP3 Review
Baofeng UV-5R OCR conversion of original PDF Manual

LK10 Talking Multi-Meter

Posted on December 19, 2012 by The Active Elements Team

Review of LK10 Talking Multi-meter

By Kelvin Marsh M0AID

The talking multi-meter has not been available in the UK for several years. Some amateurs still own the meters sold by Tandy, but I knew of several blind amateurs who dearly wanted to own a multi-meter that gave verbal feedback.

In December 2010 Tim GI4OPH found a talking meter was being sold by the National Federation of the Blind in the US. When I enquired about costs, it quickly became apparent an individual would need extremely long pockets to bring one into the UK. Although the meters sold for $50 or £33 in the US, because of the handling fees and the traceable delivery method the NFB use, a single meter would cost over £90 to import!

I started to gather interest from other British amateurs , with a view to making a bulk purchase. I soon had ten definite orders, and it was decided we would purchase twenty units, and RAIBC would act as an agent for a bulk purchase.

I spent some time looking into getting VAT and Duty excemptions, and despite phone calls and an email application to HMRC, I’m still waiting for a reply months later. A good thing we decided to go ahead with the order, regardless.

The meter itself is a very nice unit, and appears to be extremely well made. It has a LCD display and backlight, as well as a clear female voice.

The meter measures both DC and AC voltages. There are also selections for resistance, Diode, continuity, capacitance, and milliamps.

There is a ‘talk’ button on the meter and another ‘talk’ button on the positive probe. Another feature that has been highly praised by both low vision and sighted uses, is the LED light on each probe, shining directly onto the area to be tested.

The manual has been recorded by Chris G5VZ, and is available below.

Comment 1

By Kelvin M0AID
September 2013
It seems the National Federation of the Blind no longer stock the meter, and the 20 units brought into the UK have been sold. Several people have contacted me recently, but unfortunately I cannot help. I suggest you contact the NFB, http://www.nfb.org, and express your interest. If I do hear any news, I’ll post a comment here.

Comment 2

By Mastro Gippo
March 2014
Hi, I’ve seen your article about the LK10 and I’d like you to know that
I made an open source alternative for anyone needing a talking multimeter:
http://www.mastrogippo.it/2014/03/a-talking-multimeter/

Related Downloads

LK10 Talking Multi-Meter MP3 Manual

HF Vertical, dipole, and Yagi MP3 Comparison

Posted on December 16, 2012 by The Active Elements Team

I thought the following might be interesting for the newcomers to the hobby, and help explain why many amateurs use more than one aerial. I took delivery of one of the low cost verticals this week, and made some comparisons with my trapped dipole. For interest’s sake, I also included my yagi, just to see if the cost and effort was justified .

We mounted the review X80 vertical, from the Snowdonia Radio Company, on Wednesday evening 15 March 2011. It’s on a metal stake next to the corner of my fish pond. We used an antenna analyser, and established the 80m SWR was 6 to 1, but all the other HF bands 40m to 10m were well under 2 to 1. There were no radials used, in line with the suppliers recommendation, but I think this type of vertical might indeed benefit from them…

As expected, the X80 performed better as I went from 80m to 10m, and the dipole was better in the reverse direction.

As signal strengths are difficult for me to determine accurately, I’ve recorded MP3 comparisons over the last three days on 80m through to 10m. I’ve deliberately selected signals right on the limit, to show the capabilities of the aerials, after all, there’s little point in comparing strength 9 signals on the doorstep. I’ve used 3 antennas in the comparison.

A trapped dipole, which is 108 feet long, trapped for 40m, and fed with balance 75 ohm twin feeder, at a height of 10 metres. It is connected to the rig via a 1 to 1 ballun. I have marked this with one ‘beep’ in the recordings.

The second antenna is the Snowdonia Radio Company X80. It is a 5.8 metre tall aluminium vertical with a 9 to 1 un-un at the base. It is fed with 20 metres of RG213 coax. I’ve marked the SRC X80 with two ‘beeps’ in the recordings.

The third antenna is a 3 element Steppir at 11 metres. It is a rotary dipole on 40m and 30m, and a 3 element yagi on 20m to 10m. It is fed with 30 metres of Westflex 103, and there is a 1 to 1 ballun at the feed point to the aerial. I’ve marked this with three ‘beeps’ in the recordings.

I used an ATU once, for the X80 recording on 80m. All other recordings
are without any tuning.

On 80m, you will hear SV2HJQ in Greece. Firstly my trapped dipole, then the X80, then back to my trapped dipole. The dipole gave strength 9, the X80
strength 1.
80m
On 40m, you will hear VE2TC in Canada working some Spanish stations. I have changed the order of the antennas, so they progressively get better. Firstly, you hear the X80 with 2 beeps, then my trapped dipole with 1 beep, and then the Steppir with 3. I then repeat the X80, dipole, and Steppir sequence again.
40m
On 30m, you will hear VP2V/G3PHO in the British Virgin Islands. Firstly, the trapped dipole, then the X80, then the Steppir.
30m
On 20m you will hear HZ1ZH in Saudi Arabia. First the trapped dipole, then the X80, then the Steppir.
20m
Also on 20m, you will hear zl1BD in New Zealand, first the dipole, then the X80, then the Steppir.
20m
On 17m, you will hear KH2/WX8C in Guam. Firstly the dipole, then the X80, and then the Steppir
17m
On 15 m, you will hear V521NAM in Namibia. First, the dipole (no copy), then the X80, finally the Steppir.
15m
On 12m, you’ll hear ST2AR in Sudan. Firstly the trapped dipole, then the X80, and then the Steppir.
This station was worked using the X80 and 10 watts.
12m
On 10m, you will hear LU2NI in Argentina. Firstly the dipole, then the X80, and then the Steppir.
10m

G4FON Koch Method CW trainer Accessibility Review

Posted on December 16, 2012 by The Active Elements Team

G4FON Audio Review and Demonstration

By Kelvin Marsh M0AID

This MP3 demonstration is of the popular CW trainer using the Koch method by G4FON. The demonstration covers the use of the software by a visually impaired person using a screen reader.

The software can be downloaded from
G4FON.NET

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g4fon-demo.mp3

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