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As readers of this blog will know, I’ve been letting HF and particularly HF contesting take a bit of a back seat recently. No particular reason, but it’s just one of those ebbs and flows in my interests in the hobby – it’s happened before and I’m sure it will happen again.Last weekend was the RSGB’s Commonwealth Contest, often known as BERU. This contest is quite an individual one and one that you either love or hate. Anyway, that’s by-the-by, I love it and many of my Canadian friends, especially John, VE3EJ take part in it, so I always like to support their activity.I found a few minutes on Saturday evening to make some QSOs, mostly on 7MHz, where I worked John VE3EJ as well as a handful of others including 8P9AA, VY2SS, VE3JM, VO1TA and ZC4LI. I half intended to look at sunrise the next morning, but didn’t get around to it.And then my QRPP contact. QRPP is very low power – generally considered to be less than one watt. On Tuesday evening, I’d heard someone mention that it was one of the 80m CW Cumulative Contests. I tuned around quickly to see who was on and the very loudest signal was John, G3VPW who is about 3 miles from here in a village to the south of us. John was about 40db over 9! I turned the rig down to as little power as I could manage, around 100mw. Although it took me a few calls, I worked John – probably my lowest ever powered contact on HF!

As readers of this blog will know, I’ve been letting HF and particularly HF contesting take a bit of a back seat recently. No particular reason, but it’s just one of those ebbs and flows in my interests in the hobby – it’s happened before and I’m sure it will happen again.Last weekend was the RSGB’s Commonwealth Contest, often known as BERU. This contest is quite an individual one and one that you either love or hate. Anyway, that’s by-the-by, I love it and many of my Canadian friends, especially John, VE3EJ take part in it, so I always like to support their activity.I found a few minutes on Saturday evening to make some QSOs, mostly on 7MHz, where I worked John VE3EJ as well as a handful of others including 8P9AA, VY2SS, VE3JM, VO1TA and ZC4LI. I half intended to look at sunrise the next morning, but didn’t get around to it.And then my QRPP contact. QRPP is very low power – generally considered to be less than one watt. On Tuesday evening, I’d heard someone mention that it was one of the 80m CW Cumulative Contests. I tuned around quickly to see who was on and the very loudest signal was John, G3VPW who is about 3 miles from here in a village to the south of us. John was about 40db over 9! I turned the rig down to as little power as I could manage, around 100mw. Although it took me a few calls, I worked John – probably my lowest ever powered contact on HF!

Last evening was a momentous one for me on 70MHz! I popped into the shack after I’d got in from work and switched the rigs on, including the 70MHz FM rig. Andy, G6REG/M called CQ on 70.450MHz and I answered him.

Andy was about 12 miles away on the edge of Oxford and we had a great QSO as he drove down the A420 towards me. Then it struck me! By the time he got to the roundaboout just to the south of me, he was about a couple of miles away from me.

Quickly, I got the Wouxun 70MHz handheld out and called him! He heard me, despite the handheld being in the shack. We did a couple of overs on the handheld as Andy headed west, out to a distance of 2 or 3 miles. Signals were still S9. So that was great! I knew the Wouxun worked well, especially with the Garex Flexwhip, but I hadn’t actually had a contact with it. Thanks Andy! Hopefully now that the weather is improving, I will be able to make some QSOs with the Wouxun from various high spots.

And the other thing that came out of last evening’s 70MHz activity was that the Tring ‘parrot’, MB7FM is back on air. It vanished a few weeks ago as you may remember but it’s great to hear it back in service.

JT65A is a wonderful mode, and JT65-HF by Joe Large W6CQZ is a wonderful program that makes it enormous fun to operate. True, the mode only allows the exchange of signal reports, though a very brief amount of extra information (such as power and antenna) can be sent in a custom message. But so many contacts using other modes also only result in the exchange of such limited information. On the other hand, there is a certain magic in seeing faint musical tones sent by a faraway station translated into a message on your screen. Many people have said that JT65A is addictive. I agree.

If there is one problem with the mode, it is that the 50 second transmit cycles where nothing is decoded on to the screen until the end makes it easy for your attention to wander. I’m ashamed to admit it, but many is the time someone has replied to my calls and I missed it because my mind was elsewhere. So I was really pleased to discover an add-on for JT65-HF written by Laurie VK3AMA called JT-Alert. One of a pair of add-ons he has written (the other is a kind of macro tool for custom messages) it watches the decoded text and sounds an audible alert when a CQ call is received or when a station replies to your call. You can have different sounds for the two alerts, and the audible alert is optional and can be disabled. The tool can dock to the bottom of the JT65-HF window (as in the screenshot above) so the two function as one program.

I have been monitoring for activity on ten metres, which is dead most of the time. It would get pretty boring sitting in front of a blank window for hours at a time but I have set the CQ alert to a loud klaxon which will bring me running to the shack from wherever I am in the house if/when a call on 10m is received. It’s a really useful tool (though it does get a bit annoying when working on 20m and my XYL isn’t so keen on it either!)

I made a number of nice contacts on 20m using JT65A today, including CO2VE (Cuba), PJ2MI (Curacao) and LU6AM (Argentina). I also worked a fellow blogger, David K2DBK. Unfortunately my custom message to David didn’t get sent as I got caught by a quirk in the JT65-HF program that was pointed out to me later by members of the JT65-HF support group. Apparently if you start a message with 73, those two characters are sent as a special shorthand sequence and the rest of the custom message is ignored. I had actually read that in the documentation, but I’m afraid due to the onset of senility RTFM often isn’t the answer as I FTFM (Forget The Frigging Manual) immediately after I’ve read it. Oh well.  🙁

It was a fine afternoon and I needed some exercise so I took the VX-8GR and the Albrecht 10/12m handheld and went for a stroll over Watch Hill. I put out a call on the 2m FM calling frequency and was answered by Jim, G3XPD, a few miles away. I asked if he could QSY to 28.500MHz SSB and he said he could, so I was able to make my first contact with the new radio.

When I first heard Jim call on 10m his audio was clear but very weak. This was puzzling when he told me he was hearing me quite well and was running 100W to my 4W. Eventually I realized this was due to the RF gain setting of the Albrecht. It is accessed via a few button presses, effectively on a menu, so I had left it as it was set by default. This clearly made the gain very low. After winding it up to maximum (see, I’m turning into a CBer!) Jim’s modulation was rattling the loudspeaker. No shortage of gain there, for sure.

The receive audio was very clear. Jim commented on some wind noise on my transmissions, which I was able to tame by changing position so the internal microphone was shielded by my head. I didn’t ask if he could hear any FM on my SSB modulation and he didn’t mention it. That’s good, as it suggests the problem isn’t noticeable enough to prevent making contacts and there is no urgency to try the modification that is supposed to cure it.

The main problem would seem to be tuning the radio on SSB. The Albrecht AE2990AFS is basically a CB radio designed to work on fixed 10kHz channels, even though it does have dedicated ham band modes. The tuning steps of the radio are 10kHz just like a CB radio. You can press a couple of buttons and select 500Hz steps but you can’t tune the band this way. You can tune in 500Hz increments up to just before the next 10kHz multiple then the VFO rolls back to where you started.

There is a clarifier or RIT control which is designed to tune in stations that are slightly off the 10kHz channel. It’s range is something like +/- 5kHz so it is quite touchy. There is no centre detent to mark the off position. What this all means is it’s quite hard to tune the band looking for signals and if you do tune someone in the chances are you’ll call them off-frequency.

A better solution, in my opinion, would be to dispense with RIT and make the clarifier change both the transmit and receive frequency. But if it was possible to do that one wonders why the manufacturer didn’t. I imagine that the control works by pulling an oscillator using a varicap diode so there is a risk of making the FM problem worse under the varying load conditions of SSB transmission. But if it could be done without affecting the transmitter frequency stability that would be a mod worth doing.

In the wake of the Japanese nuclear disaster there has been a surge of interest in interfacing Geiger counters to home weather stations so that radiation levels could be monitored via APRS. When you think about it, it seems a very good idea. Even if the measurements were not of lab grade accuracy, they would be good enough to show what was going on. It could avoid unnecessary panic – and equally make it impossible for officials to hide the existence of a radiation leak – if data from a network of amateur radiation monitoring stations worldwide was publicly available. This could be a real application to make APRS relevant even to the general public.

A standard for representing radiation measurements in APRS weather packets is being worked out as I write. The question is how to interface a radiation monitor to an APRS system and what hardware is needed to measure the radiation? Unfortunately, if not surprisingly, the final bid price of dosimeters on eBay has gone through the roof in the last couple of days. But in any case they all seem to be standalone instruments with no computer interface. I don’t know if a homebrew device would be possible, given that calibration would be needed, but if someone could develop one I think it would be a popular project.