Thursday, 29 November 2018

Spennymoor Rally and progress since the 1970s

On Sunday last I visited the Bishop Auckland Amateur Radio Club rally at Spennymoor, County Durham. This turned out to be quite a big event in a pleasant hall in the Spennymoor Leisure Centre, easy to find and well attended.
General view at Bishop Auckland Amateur Radio Club Rally 2018.
Sometimes I think about rallies and decide "I do not need to buy or sell anything, so I will not go", which seems to ignore the obvious fact that the benefit of rallies is who you meet rather than what you buy. Anyway, the traders soon show you that there was something you did need, it was just something you never realised existed.

I did manage to buy a couple of things and there may be more on those in a later post, so it cannot be said that I bought nothing. The real benefit was meeting lots of people I usually only contact via the radio.

Despite being a person who prefers to keep a low profile, I was wearing a badge which shows my name and callsign. I am of course instantly recognisable anyway, being probably the only middle aged overweight man there with grey hair (almost none on top), glasses and wearing an anorak showing too much tummy ... can't be many amateurs who look like that.

Well, no, better show the badge.

I had long conversations with Graham, G8DST, Gordon, G8PNN, Brian, G8KPD, Derek, G1ZJQ, Clive, G4FVP, and Eddie, G0EHV. I also managed to say hello to Chris, G4FZN. The conversation with Graham, G8DST, was wide ranging. We did agree about developments in Software Defined Radios, many of which are excellent - though some manufacturers seem to overprice what they have on offer. This was a great discussion. We had never met before and we hardly share a band or mode in common. I might be right when I say that amateurs share a common bond even if the areas they specialise in are different. Graham said he reads this blog, so his judgement is clearly first class.

A long blether also resulted from meeting Gordon G8PNN. Once again Gordon managed to get me thinking about 1296MHz. It should be recalled that I had hardly ever strayed above 146MHz before this year, so that would be new turn of events for me. I have to admit now that for a few months I have been secretly reading the Microwaves section of the RSGB's magazine Rad Com and it all seems rather interesting ... but no, not right now. So it was timely to meet Gordon. Great also to meet Derek, G1ZJQ who I usually encounter when he is on hill tops. Brian, G8KPD, Chris, G4FZN and Eddie G0EHV are regulars during activity contests which I do appear on from time to time. Clive, G4FVP, is someone I have worked on the shortest Es contact I have ever made (151km).  So, all in all, I had a great time and learned a lot.

Moving on, there is still something nagging in my mind about the earlier comments on VHF in the 1970s. Several of you commented or sent emails about this period, when over a couple of years local VHF traffic moved from geriatric equipment and wasteful methods to miniaturised modernity. 2m DX moved from the preserve of a few CW and SSB enthusiasts into the mainstream. Those of us who lived through it look back with fondness to the dying days of a 144MHz band which sounded like HF must have done 40 years earlier (with some of the same equipment still in use).

The thing which is nagging in my head was first brought up in an email to me by Bruce, GM4BDJ. Bruce  said that at the time many locals built the G8ARV design for an FM transmitter. This reminded me that the NBFM Handbook I mentioned also made a big point about how easy it was to build a 2m FM receiver and transmitter. The focus was not only on buying ready made equipment, though home built may have been physically bigger and perhaps less powerful in terms of output power. Bruce is correct - home building was the route many followed then.

This thought has been churning about in my mind. Well actually I have taken Bruce's point and run away with it in some strange direction, so the mad stuff in this posting is all my own fault.

Why so little home building now? Then of course it was relatively easy to get frequency stability with a crystal (which somebody else always made). One crystal would be all you needed, before repeaters arrived on the scene. Now it would be quite a task to build a frequency synthesiser and make it passable in terms of unwanted phase noise. Now FM stations routinely use 50Watts output power, something which would have been the preserve of very few back in the 1970s. But then, by a strange turn, we can now find some of the things we need on single chips, if we can accept that soldering resistors is something we can put behind us.

The early pioneers in amateur radio, back before the Great War, would have not only built their own radios, they would often have built their own components. They might have wound their own coils and built detectors. Very soon basic components such as resistors and transformers would have been available for their needs, and specialist radio items too. Later there emerged a tradition of building radios out of standardised commercial components, though I am not sure what the even older "old-timers" said as they could recall building Leiden Jars from scratch. Maybe "these modern folks have it easy in the 1930s with their factory made capacitors. But can they open capacitors up and fix them?".

At about the time of the 2m revolution, Yaesu brought out the FT101. This featured plug-in circuit boards. In the event of a fault you could pull the faulty board out and send it back to the supplier to be repaired (or so the advertisements said). You could buy an extender board to allow you to fix the fault yourself, with easy access. This raised the obvious question, why not just change the faulty board for a new one? And so, at a stroke, we moved from making repairs by using standard components to just changing boards. Behind the sceptical views of the 1970s old timers was the (correct) opinion that minituarised equipment was going to be hard to fix. You would end up having to change the entire board (and never mind the problems with the wafer plugs and sockets on the boards).

And so we stagger to today. The next step in the progression from making components, to changing components, to changing boards, is the inevitable .. just change the radio. I met a technician who was responsible for the radio equipment on a huge cruise ship. Unlike the radio officer of old he had no responsibilities for operating, he just repaired the radios by ... changing the entire radio. Rather than a box of components he has a store of complete radios to plug in. And why not? The radios are now small and cheap compared with years ago, and we all want cheap cruises (?).

Apparently the next step is for the ship to go for a refit and get the entire suit of electronic equipment changed at one go. Why wait for failures? I can see the logic, rather like the fluorescent lighting in a former workplace of mine, where every tube was changed when one got faulty. Once you get the ladder out you might as well do them all.

So I suspect that the next thing I hear about an amateur is that as the green meter bulb has gone out in their LinearAmp Gemini 4, they are getting a new shack. New bench, new PSUs, new radios, and new shiny leather chair. Just go to the shack shop, where you just say what bands you want to work and give them your credit card number, and they will deliver the entire thing. Oh, you do need the skill to plug the mains plug in (and turn the switch on) - a special Plugging In Training Course will be available at extra cost, though switching on is at owner's risk.

Actually, the meter bulb in my LinearAmp Gemini 4 amplifier has stopped working, and I have just ignored it. Amateurs are (or should they be?) made of sterner stuff. We cannot, however, ignore progress. We need to be part of progress. I could not build the superb geared VFO drive on my FT101 when I bought it, but that did not stop me using it and it never did fail. Just because some of us cannot built every bit of our gear from 6BA screws, Meccano, and rubber bands does not make us less able to comprehend our hobby. I think we need to be somewhere in between builders and buyers.

Sure, we lost something when we ditched the Pye Cambridges, the Philips 1000s and the AR88s. At the same time I am not going to set about building an IC-7300 on Veroboard out of components. Progress will inevitably raise the size and complexity of the unit by which we repair things - up from components to boards and even to entire radios in some cases. That does not mean that we do not want to understand how it all works, and even tinker a bit.

I know that Bruce has recently built several HF transceivers with success. I am a bit envious of him there. It is possible to buy kits and you can also find hours of innocent fun piecing together a station. I know some people build their own SDR transceivers (though I have not yet met anybody who wrote all the software from scratch as well). It can be done and it is very satisfying. Nevertheless, I think we should recognise that some of us have learned more about radio because we don't need to build everything from scratch. If I had to build something to run MSK144 on 432MHz out of components I doubt if I would ever get beyond the first stage. On the other hand, if I could only be still enough to appreciate 80m CW I just might have more money in my bank account and I might feel a bit more satisfied with the hobby. Sadly, I don't feel like doing that, but I can share the joy of those who do.

Thanks Bruce for reminding me that the constructional approach was to the fore in 1970, and in many ways it still is. Construction should be at the heart of our hobby.

I think that progress will continue to raise the complexity of the unit which we can replace, in effect by reducing an entire stage which once occupied a large printed circuit board to a single chip. In fact, the whole radio might go on a single chip, at a price we once paid for a component. At the same time, what a magnificent thing it is that we can still build meaningful parts of our stations.

Despite all this we should recognise that we have a special right conferred by our licences to build our own equipment, alter commercial equipment, or assemble our own stations. I hope we never lose sight of that.




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