A dongle for the FT-817

If you have used a Yaesu FT-817 on SSB you'll have probably been annoyed by the lack of a TUNE button to generate a steady carrier for antenna tuning. You usually have to press the MODE button a few times to select FM or PKT, use PTT to send a carrier, then change mode back to USB or LSB. It isn't one of life's greater annoyances, but it's a nuisance all the same, especially if you use an antenna like the AlexLoop which needs retuning every time you change frequency.

A couple of weeks ago I received a letter from one of my blog readers, John G4HUK, enclosing a Quick-Tune Dongle that he makes for the Yaesu FT-817, FT-857 and FT-897 rigs. It's a neat little gadget that plugs into the ACC port on the back of the radio. What it does is let you generate a tuning signal in SSB mode by double-clicking the microphone PTT. Simple but effective! It won't be so useful for home users who have a CAT cable plugged into their ACC port already, but for SOTA operators and other exponents of outdoor radio (apart from CW operators who can just hold the key down) it could be a godsend.

The Quick Tune Dongle installed on the back of the FT-817

The dongle didn't work for me at first until I set the baud rate of my FT-817's ACC port to 9600. This is explained in the 'manual'. The instructions also explain how you can reconfigure the dongle to change the way it works. By default it will use PKT mode to generate the tuning carrier and ignore double-clicks made in any mode other than USB and LSB, which I think will suit most people.

I think it is an ingenious little gadget which you can get from HUK Electronics for £15.95 + postage. Here's a video of the dongle in action.

Third-party Kenwood accessories

Ebay is a good place to buy accessories like speaker/mics and headsets for your radios. A few years ago I used it to buy a speaker/mic for my Kenwood TH-F7E. After I sold that radio I used the speaker/mic with my TH-D72. When I tried it with my old TH-205E however I found that PTT didn't work. I soon established that the reason was the genuine Kenwood accessories used a monophonic 2.5mm plug with only two contacts, tip and sleeve, for mic audio and PTT. The third-party accessories from eBay used a stereo 2.5mm plug with tip, ring and sleeve, but there was no connection to the ring. It looked as if the plug in the radio was trying to make contact in the area of the ring. This obviously was OK for newer Kenwood radios but with the 205E there was no ground connection for the PTT.

Ring and sleeve of the 2.5mm plug should be connected

My first thought was to open up the speaker mic, find the wire connected to the ring and connect it to ground. However I soon found that the cable of my speaker/mic had no wire connected to the ring at all. My only option was to try to bridge the two contacts together using solder. This I did, and the speaker/mic then worked with the TH-205E.

The Wouxun KG-699E and the Baofeng UV-3R+ also claim to use accessories with a Kenwood-compatible plug but just like the 205E I found that PTT did not work. I have just performed the same modification to the plugs on a "Kenwood-compatible" headset/boom mic and also one of the earpiece/mics that came with the Baofeng and Wouxun so that they would all work with all four radios. It is easy to do, but you need to take care as it's easy to melt the plastic parts of the plug and you could easily ruin it if too much heat is used.

Using a sharp craft knife cut away a small section of the black plastic insulation between the ring and the sleeve of the 2.5mm plug to reveal an inner metal sleeve. Open this up a bit more using the edge of a jeweller's file. Then make a solder bridge between the ring and sleeve. You need to apply heat using the edge of the soldering iron bit to the inner sleeve in order that the solder will bridge the gap. Apply the soldering iron for as short a time as possible to avoid melting the plastic insulation and destroying the plug. I used Blu-Tac to hold the plug in a steady position whilst soldering.

After you have bridged the contacts use a jeweller's file to remove any excess solder from the plug. You should also smooth the plastic insulation between the plug contacts which may have melted and bulged a bit. The plug should be completely smooth between the contacts, the solder bridge and the insulation. It should plug easily into the socket on the radio. If it needs a firm push then try a bit more filing until it goes in easily. You don't want the plug to get stuck in the radio nor for it to damage the socket contacts if force is needed to insert or remove it.

I accept no responsibility for damaged plugs or radios as a result of trying this modification. However I have done three of them now with success each time so it is possible with care. Now my "Kenwood-compatible" accessories will work with old and new Kenwoods as well as the Baofeng and the Wouxun.

Logging assistant

When you are out in the field, especially on a windy hilltop, logging the contacts you make can be a bit difficult. One hand holding the radio or microphone leaves only one hand free to hold down the log book and write in it. If you're using a hand-held and standing up to get the maximum height gain, it's even more awkward.

A few weeks ago I hit on the idea of using a personal digital voice recorder. Initial researches suggested that they were a bit expensive - many models sell for around £70 or more. But diligent searching on eBay revealed that it was possible to buy them for much less than this.

The one I got is an Olympus VN-100 Digital Voice Recorder and cost £15.99 including free postage. It was described as "refurbished to new condition by Olympus." This might be an indicator of a product that tends to fail and has a high number of warranty returns. However, this particular one was indistinguishable from new, works fine and is simple to use. It isn't the colour I'd have picked if I had a choice, but price and functionality were the principal considerations.

I don't know what the differences are between the VN-100 and the more expensive models apart from colour, probably storage capacity. However this model has capacity for more than 13 hours of recording - more than adequate for my purposes.

I find the VN-100 easy to operate with the hand that isn't holding the radio. You just press one button to start recording and another to stop. A bar meter shows the level of the audio input. You can either say the callsign, time and whatever else you are interested in logging, or just point the device at the radio and make an off-air recording. At home it could be a handy shack tool for recording unusual DX contacts.

The only problem I found is that the voice recorder is just as sensitive to wind noise as the microphone in the radio. More than once I have returned home to find a recording was unintelligible. However, mishaps like this can probably be avoided with practise.

I'm finding my digital voice recorder to be an indispensable companion on portable outings. It's also handy for jotting down ideas for blog posts that occur whilst you're out and about!