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A Home-Made VHF ‘Civvie.’

Started by ThePillenwerfer, May 04, 2023, 07:09:29 AM

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ThePillenwerfer

FM broadcasting started in Britain in the late 1950s but it was well into the 1980s before it became the norm.  Before it even started regularly JasonKit started to sell FM Tuners in kit form.  I got hold of one of these around ten years ago but never did much with it.  I rigged a power supply for it and made a crude box for it but that was about all.  Back in 2020 I thought it was time I either did something sensible with it or sell it, though I wasn't keen on the latter as I doubted I'd recoup what I'd paid for it.

Making an amplifier for it was no problem but a case that looked something like nice was more of a challenge as it had to be something I was capable of making and preferably using wood I'd already got — apart from the cost as I can't drive getting new stuff is difficult.

I then hit on the idea of making a case based on the Wartime Civilian Receiver.

During the Second World War domestic radios weren't being made but the government still wanted the population to hear its propaganda so a radio was designed which would be cheap in both materials and money to fill the need.  Thus was born the Wartime Civilian Receiver, sometimes erroneously called a Utility Radio.  Now I must be some sort of pervert as they have the reputation of being one of the ugliest radios ever made but I like them.
 
However, there's more to it than that.  Firstly they didn't come on the market until July 1944 so these TV shows and films showing a family listening to Churchill's 'Finest Hour' speech on one are nonsense.  As for economy they managed to make it look cheap and austere but they cost enough to be taxed as Luxuries and inside is a huge power transformer containing a load of strategically important metals.  It would have been much better to have used a dropper as this would have been cheaper in both terms of money and resources besides allowing the set to be used on DC mains, of which there was still quite a bit at the time.  As it was people with DC mains would have to use the battery version, the batteries for which took more resources.
 
The truth is that most of these sets were flogged off cheap after the War on the surplus market.  At that time kits were also made so that Long Wave could be added as originally they were Medium Wave only.
 
I did have one but was always disappointed in its performance.  I even borrowed another from a friend who is far more knowledgeable about radio than I and found mine performed SLIGHTLY better than his.  Besides that there's nothing on Medium Wave these days that I've any wish to listen to so it ended-up on e-Bay.
 
I managed to get a reasonable idea of dimensions from photographs found on-line.  For feet the originals had two strips of wood running front-to-back underneath.  These are all very well but such things have a nasty habit of scratching whatever they are stood on so I fitted four rubber feet salvaged off an old computer case instead.
 
The amplifier is a μA741 and a couple of transistors.  This is powered by the LT via a voltage doubler and an LM317.  The LM317 is there to get rid of hum as the actual voltage doesn't matter that much.

Knobs were a bit of a problem as I couldn't find any new ones I liked —  part of the trouble being that there are very few without dots or lines engraved in rendering them unsuitable for tuning knobs — and people want silly money for old ones.  I therefore made my own out of oak.

Only afterwards did I learn that I had used something very appropriate.  The oak was actually a bit of furniture leg that the same friend whose radio I'd borrowed had given me.  He told me that the leg was off a Utility sideboard that his wife's grandmother had bought after her house in Liverpool took a direct hit in the War.

More information on the real ones can be found on Wikipedia and this collector's site: https://www.wartimesounds.co.uk/

countryman

FM was the cherry on the cake back in the days ;-)
You did a very nice job with the housing - the wood sure is better quality than the original. I can't say the design is ugly?! Looks pretty modern and straightforward for the time.
Is it a superhet design or a superregenerative FM receiver?

Here in Germany, the market was flooded with cheap mass produced radios in the 1930ies. Someone wanted his propaganda being heard very urgently, and I have to say his was much worse than yours  :(
The "Volksempfänger" (people's receiver) came in a couple of types but was generally a simple AM tuned radio frequency receiver. Unlike the Wartime Civilian Receiver it used a voltage dropper and a rectifier tube, no transformer. Beware of the life chassis! And the design was worse, too.
Post war, FM made it quicker here than in other countries, the legend says because Germany was no longer allowed to use enough or strong AM frequencies. Not sure if there is any truth in it. Likewise, kits were available to upgrade existing radios. First, superregenerative FM tuners were the norm but quickly superhets took over. Some late 1950ies valve radios still beat many modern FM tuners in sensitivity and sound quality (while not providing stereo).
Max Grundig started a business with AM kit radios in 1945, the company later was Europe's biggest electronics company for a number of years. All gone now, it's just a brand name owned by a Turkish trading firm nowadays.

ThePillenwerfer

It's a superhet with four EF91s and two OA81s.

Volksempfängers are very rare in this country.  Didn't Germany also have cable audio broadcasting back in the '30s?

It's often claimed that Britain had the first regular high definition television service but the operative part of that claim is "high definition."  German television started on 22 March 1935 using a 180-line system but Britain's didn't start 'til 2 November 1936 using a 220-line and a 405-line system for alternate weeks for three months and just 405-line thereafter.

Not many Germans or Britons owned sets as they cost as much as a house but Germany had public Fernsehstuben (television parlors) where people could look-in.

We've also got Germany to thank for magnetic recording tape.