Jasonkit VHF Tuner.

[Joe]

I got this tuner a few months ago.

The main problem I had was lack of a power supply. I'm no saint and I admit that the idea of not bothering with anything so refined as a transformer for the HT did cross my mind.

I bought a wrecked Philips at Golborne just for its transformer. This was lucky as it proved to be about the only serviceable thing in it!

Apart from that I had to knock up a pre-amp and make the case.

       

I'll not fit the top properly until it's had a decent soak. My plan is to use it in conjunction with radios which lack VHF but do have Gram sockets - the P75 is looking worried!

- Joe

[AlanBeckett]

That looks very promising young Joe, although it does look a bit like a Casket.
Perhaps you could get Col to make you a brass plate for the top.
Seriously, how well does it work? Jason were well known at the time for high quality fm tuners.
Alan

[Joe]

It works very well indeed. Plugged into the workshop Hi-Fi (a Philips 302 for those who care) it sounds as good, and maybe a bit better, than the one on that.

There's nothing worth hearing on VHF in tonight, or not until after bed-time, so I'll see how Ken Bruce sounds in the morning.

- Joe

[tiv48]

wait till you find a live concert on radio 3
rob t

[Joe]

I ended up being out for a good part of the morning but did manage to have it on for long enough to find that it's very good indeed.

Alan isn't the only one to have had a nip today as I touched a charged smoother too.

Here's the circuit for the PSU and pre-amp. I've pondered the wisdom of posting it as it will probably pain Dr Mark. :D

   

- Joe

[tiv48]

i think there may be a diode missing from your diagram jo a nice single ended valve output stage would be nice you could use the pye output tx?
rob t

[Joe]

Well spotted, Rob: two actually. Building at as drawn would be interesting to say the least!

Hopefully this is right:-

   

- Joe

[Yorkie]

Looks good to me Joe - neat way to stabilise the HT with 2 x 100V zeners in series.

I remember the Jason Kit FM Tuners being advertised in the (long since defunct, sadly mourned) 'Radio Constructor'. They weren't cheap by the standards of the day, but were well regarded.

[Joe]

The credit for the zeners belongs to Alan: left to my own devices I'd have used a 200V one but he advised against that in the absence of a couple of icebergs to mount it between!

I may well follow Rob's valve amp idea but I think it will be more use as a Tuner than a Radio. Had the wreck's OPT been usable I may well have had a go. I must say though that I think valve stuff sounds so good because of things like the speakers and cabinets and it was built to a standard rather than down to a price. I do remain open-minded though.

- Joe

[Joe]

I've now made and fitted the back so, apart from a bit more polishing, can declare it finished.

   

I'm still amazed by how good it sounds.

- Joe