I built a radio just for fun.
 

It all started when I was sorting the garage out (being shielded I got bored enough to take it on!) and amongst the "stuff" were some metal pattress boxes. Too good to throw out I thought!
A quick check showed that a B7G valve base fits the knockout holes, game on.
A look through "Radio" by Edwin Bradley took me back in time and a plan evolved.
The result a one valve regen (page 38 of the 1965 edition) from all salvaged parts and a few hours of enjoyable time.
I'd forgotten how sensitive these little circuits can be,it happily copes with dragging Radio5 out without being swamped by Caroline (I'm about 10 miles as the waves go from the Caroline transmitter)
I may move on to 2 valves, the SW receiver in May'65 PE which I first built back then.

Re: I built a radio just for fun.
 

Excellent , now I know why I was saving the twin back boxes from my house wiring days, it paid a lot more than repairing t/v's .:) Mick.

Re: I built a radio just for fun.
 

Please take this the right way - that looks like a fairly stress-free project and I find I am increasingly seeking to find projects that are stress-free.

This is a hobby that get a bit too complex sometimes and I no longer find that attractive. I definitely think my preferred homebrew projects are the ones that work the first time they are switched on 8-). Maybe I should stick to assembling kits?

B

Re: I built a radio just for fun.
 

Good work - A one valve regen is something I've always wanted to make, as a preteen I had a go at a superhet, no easy feat using a plumbers soldering iron heated on the kitchen gas ring, needless to say it didn't work, I had to eventually settle for a crystal set which work fabulously.

Re: I built a radio just for fun.
 

What a lovely little project. Satisfaction from such simplicity. Well done.

Aub

Re: I built a radio just for fun.
 

Nice and satisfying in its elegant simplicity! Those metal pattress-boxes have multiple uses; you can easily squeeze a second B7G valve and a small output-transformer into the double-width ones to make a little audio-amp (EF91/6AQ5 in my case).

If you want something a bit prettier, the 'metalclad' surface-mount boxes could be worth a look: you can even get undrilled blanking-plates to serve as a cover for the bottom.

Re: I built a radio just for fun.
 

Thanks for the kind words gents..yes it was very therapeutic ,a little bit of head scratching ,a bit of metal bashing, and I got the pop rivet gun out for the first time in years.
I never thought about getting the gas heated iron out although I still have some.
It didn't work first time I had the feedback winding reversed!

Re: I built a radio just for fun.
 

Very clever, the next stage is to make a nice little case to mount it in!

Re: I built a radio just for fun.
 

That would never have crossed my mind. Brilliant idea!

Re: I built a radio just for fun.
 

Any chance of a scan of that circuit, please?
Graham

Re: I built a radio just for fun.
 

The other useful cheap [at least, they used to be] boxes are electricians adaptable metal boxes, complete with knockouts, and a relatively thin front panelsizes afair from 4x2" upwards

eg
http://www.toolstation.com/metal-box...ck-outs/p91938

johnb g8jmb

Re: I built a radio just for fun.
 

Certainly Graham
I used all salvaged components..the coil is unknown but I added turns to make 200microH (ish!) for the MW tuned coil the others measured 1500 and 2600 and I used the 1500 one as the feedback. The other is currently unused ,I plan to try and get it to tune LW.
Its all very much "suck it and see" buts its fun and relaxing just to play!

Re: I built a radio just for fun.
 

Mr Camm would have approved.

Re: I built a radio just for fun.
 

That looks very EF91 worthy - I've had a couple of TRF coils laying around for ages.... maybe at the weekend.

Re: I built a radio just for fun.
 

If you use a similar "chassis" to mine Sean a B9A base will fit the holes.

Re: I built a radio just for fun.
 

He certainly would!

Super job! And thanks for the circuit, too.

Re: I built a radio just for fun.
 

Your use of a back box as a valve chassis is inspirational!

Re: I built a radio just for fun.
 

Certainly is - another excuse for a bit of skip-diving!

Re: I built a radio just for fun.
 

The use of back boxes is just brilliant. You could go back to the 1920's and use single gang boxes and put a stage in each box.

Re: I built a radio just for fun.
 

And join them with sleeves and those brass screw things (the stuff conduit uses).