Sunday, 25 February 2018

2m and low signal work, plus the "good old days".

In my youth there was a programme on the television called "The Good Old Days". I found it excruciatingly bad. It was a collection of old music-hall acts, has-beens and superannuated old crooners. It was topped off by an audience of cranks wearing Edwardian costumes. To make matters worse, Leonard Sachs, who was the compere, was dreadful.

I see that some wallpaper daytime TV channel is re-showing this putrid wallop. I took a look. It hasn't got much better over the years.

But we loved it. There were only two channels to watch anyway, and "the other side" was probably showing camp rigged fake wrestling featuring over-oiled monsters pretending to hurt each other. Or maybe motor bike scrambling from a muddy field in Uttoxeter.

But we still loved it. We didn't have much choice. Not much scope for dissent in those days, and now I make a life out of dissent.

Anyway, Bruce, GM4DBJ, rightly pointed out to me that there was period of "good old days" on 2m before the ones I was referring to in my earlier post on this topic. More of that in another post shortly.

I doubt if many current-day 2m operators could credit the way we used to operate on that band, and indeed perhaps I have chosen to forget it myself. But it was fun and we loved it.
Sometimes all I find on 2m from here is a choice between listening to the local repeater GB3DU sending its callsign ident (boring) or watching the Fairseat beacon, GB3VHF, chuntering away on JT65B (probably more entertaining than GB3DU). Automated signals from 10km away and 532km away, but no people.

Actually the past couple of weeks have been better on 144MHz, as maybe I have been trying harder.
144MHz contacts at GM4FVM 9 to 25 February 2018

This, of course, is small beer. But that analysis hides the fact that I worked Belgium (twice) when I have only had one opening before into Belgium from here in almost ten years. Denmark isn't bad on tropo (707km). Is it thanks to FT8? Is it thanks to me feeling more motivated? Maybe, but either way, I have been getting south over Ayton hill into places that are usually difficult. Doing in on an otherwise flat band is even more encouraging.

That I managed this at all is due to the encouragement of Jeremy, M0XVF and Gordon, GM4OAS. These guys are sticking with it and trying to work some stations. They kept my spirits up and I can see that I should make more effort.

And yet my frustration with 2m continues. These are better results, but they are still not good. Of course there is always the option of getting to the keyboard and complaining about it all here. And I do, but that does not really solve the problem. I can blame the lack of a decent VHF radio here, or gurn about everybody else here. This brings me some short term satisfaction but I need to make progress as well.

So in the spirit of amateur radio, I recognise that complaining is no way forward. A change of plan is needed.

I could always try even harder.

Is trying harder in the spirit of amateur radio? Not on the vulgar websites I occasionally read where blaming everybody else seems to be the Thought For The Day. But for me, working on the FT-817 with mods and add ons is better than complaining about it (though doing both is nice too). And now it looks as if the FT-818 is actually going to be WORSE than I thought, so I can say "I told you so" sometimes. These are insignificant successes and complaining leaves me cold in the longer term.

So how can I do better at 2m? Why do I only run 200 Watts? Couldn't I get a full legal linear, or apply for a 1KW special permit? What about a new rig? The IC-9700 is at last in the course of development, and it might be a contender for 2m rig for the future. Sure, those are perfectly plausible ways to go. Instant gratification is the way of our times.

This is GM4FVM we are talking about here. He does not do things that way. How can I get more from what I have? This is a good plan but it has already come a cropper.

First step - set some sort of target. Can I work somebody on Earth-Moon-Earth? Not that I want to become an EME regular, but that looks like a pretty good target to set. Improving my weak signal results to even a basic-grade EME standard will do everything a power of good.

After quite a bit of trying I just managed to prove what I already knew. An IC-7100, a 200W linear with inbuilt preamp in the shack and a single antenna with no elevation is not quite up to the job. I could see all sorts of folks chatting away - on the cluster - and saying they were calling CQ, but I could hear nothing on the IC-7100 even at low elevations. Having an antenna in just one polarisation does not help me.

To set a baseline I decided to try listening for HB9Q. Everybody said that should be easy as they use a 15m dish and plenty of power.
HB9Q heard via Earth-Moon-Earth path at GM4FVM on 20 February 2018

I listened to HB9Q for an hour and 38 minutes that day, even without elevation. That was almost as interesting as the Fairseat beacon, and the Moon is a moving target too. I learned that my efforts to date had got my rudimentary EME set-up working fine as far as it goes. Frequency correction perfect (110 Hz low), antenna direction perfect (was several degrees out). It works for HB9Q. As for actually hearing anyone other than HB9Q - forget it. But it looks very good on PSK Reporter...
PSK reporter on 20 February 2018
A minor 2m weak signal victory at last. I did not dare to transmit and before long my output power was reduced 50 Watts anyway.

So what is to be done?

As Mr Scruff pointed out in his seminal 1999 record "Get a Move On" (with a bit of inspiration from Charlie Parker and Shifty Henry) "You had better keep moving, or you'll be left behind". And so that lyric became the theme for my 144 MHz improvement programme.

Maybe "Spandex Man" is a better Andy McCarthy track musically, but Get a Move On still motivates me. In addition, both tracks come from Mr Scruff who appreciates a good cup of tea, just like myself.

Wallace "off of" Wallace and Gromit appreciates tea too, of course. Miniatures of Wallace and Gromit peer down at me now, from the top of the shack cupboards.

Following Mr Scruff's lead, what needs to be moved to avoid being left behind? What about my mast-head preamp? I don't have one.

No point having a linear or a new rig if you cannot hear weak signals. Right. Get a mast-head preamp, plus a sequencer to stop me blowing it up.

New co-ax. It is already here, in the shack, but with snow predicted that will take a week or two. As my 2m antenna is already fed by fairly good spec Ecoflex which dates from 2014, I will move the Ecoflex to the 4m antenna and install some of the Hyperflex which I already have. The specifications are much the same but the new stuff should go on the highest frequency and 4m will certainly benefit because either one is much better than the ancient RG-213 on the 4m antenna.

Right, so new co-ax is under way. New plugs and sockets next. N-types all the way of course. That cost almost £100 in plugs and sockets alone. First of all a new N-type on the IC-7100. This is an easy modification which does not even involve soldering.
IC-7100 at GM4FVM with replacement N-type socket fitted on the VHF/UHF side

Then it came to installing N-type sockets to the linear. Oooops. At this point everything came to a juddering halt.

Before I even touched it, my linear started playing up. My wonderful long-lived ultra-reliable Microset suddenly presented a high SWR to the rig on transmit, and the relay began chattering on receive. A hard look inside by me resulted in another decision. The linear is to be replaced too. The Microset is fine for general use, but it is not quite up to the job for EME. I need coaxial relays. The mast-head preamp will make the Microset's preamp redundant anyway. So time to advance on the linear front too. I have resisted it for years, but new 2m linear is needed for this purpose.

I could see all of this coming and I was avoiding doing anything about it. I will end up changing everything from the output socket on the rig to the input socket on the antenna. I may even change the antenna. Changing everything is a strange way of getting the best from what I already have, but it sure beats the full cost of going into the EME big league.

So what about the rig then?

Yes, following all my griping about the lack of a good VHF rig (link above), the fact remains that a good transverter is still my preferred path. The IC-9700 may be great. It probably will be. But it covers 70cms which I don't do, has options for 23cms which I don't want, and viewed as a single band rig it is hardly going to make economic sense. Haven't I got enough rigs already?

I am now focusing on a transverter and I have fair idea which way I will go.

So that will be that. Everything 144MHz from the microphone to the antenna socket will change. And all to achieve better results on EME which I do not intend to concentrate on. EME is not the end point of this journey, it is just the measure I am using to move things along. I need to reach that standard and then I will feel fairly sure that my tropo, aurora, meteor scatter and everything else is as good as it reasonably can be without going the whole hog for a competition standard station.

If it all sounds a bit drastic, it is. I was not expecting to replace the linear but it seems to be the right thing to do just now. I will not get a stonking high-power linear but then I do not want one anyway. I will not get a new rig. However, I will improve everything a bit, and I hope that the combined effect will show the improvements I feel I need.

There was none of this in the "good old days". Then you made good and mended. Simpler times, but I still feel happier living in the here and now.

Hey, there is a saving here. In true "make do and mend" style, I have moved the temperature controlled fan from the Microset to the back of the FT-817. Or one of the three fans, so I had some wiring to do. Now I have a full 4W output on 10m WSPR. 3dB improvement, as good as a linear.

There you are, an off-setting saving. You cannot say that I am a reckless spender. Homebrewing is at my heart still.

I will let you all know how this develops.




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