Home Made Two-Valve AM Radio

[Theodosea]

As promised here is my two-valve home made radio,

I am a regular Watcher of Michael Dranfield's TV repair channel on youtube and every December he picks a project from one of the old radio construction mags and builds something. In 2024 it was a TRF two-valve radio using 2 EF50's - this was featured in Practical Wireless August 1955
So last summer I  thought I would have a go at building this radio. I managed to get all the components from Burnetts in Lincs - including the Wearite MW coil! the  chassis was a piece of aluminium bent up at my local engineering shop. The case was made from ply and I clad this with teak veneer.

Down here in Southampton there are now only two stations on MW - both sports stations, and for this radio to work I have had to rig up a short vertical aerial and a copper earth rod just behind the garage. The volume is pretty decent for my garage/workshop and quite clear, there is no signal drift. All in all very pleased with this radio.

Regards Nick

[ppppenguin]

Very neat and tidy. I don't think I've ever seen EF50s rebranded Pinnacle.

[Kalee20]

I echo Jeremy's remarks!

It does look the business - and I'm surprised that there was enough demand for Pinnacle to deal with EF50's.

You'll have to knock up a couple of pantry transmitters to help fill your dial!

[ppppenguin]

@Kalee20, who is Jeremy?

[Theodosea]

I had never heard the term 'pantry transmitters' before but assume this must mean a low-powered transmitter to relay signals from FM to MW for the purposes of bringing a vintage radio to life!

I think at some point in the near future medium wave is going to fall silent so I will prob need one of these, they are available ready-made on Amazon,  but what happens when FM is eventually switched off I wonder? DAB radio has it's problems and I am not a fan, I do have a Sony DAB portable in my garage/workshop but when I turn the lights on I lose the signal completely - come the winter and needing to put the lights on during the day I will have to whistle!!

PS I don't know wo Jeremey is?

[Mike Watterson]

FM probably won't be turned off in UK. DAB is no use for very local / community stations and lower coverage.
Certainly not in Ireland. National DAB only reached about 45% and was turned off years ago. There are some commercial trials. Local radio doesn't want it.

I use Satellite radio to feed cheap FM transmitters (legal & sold to feed car radios from phone or mp3 player). I may add LW and MW. Perhaps R4 on 200 kHz. R. Ulster, R. Scotland & RTE on MW. I've a 12 way multiswitch and basic Sat only boxes are cheap. All runs off our Solar UPS.

There are stupid & overpriced AM transmitters on Amazon & ebay, One transistor & a 470 kHz ceramic resonator plus a tuned collector gives 940 kHz. Or a PC and some fancier HW to simulate entire MW!

[Doodlebug]

There was another version sometime ago. had 3 EF50's with plug in coils for short wave bands only.

[Kalee20]

@Kalee20, who is Jeremy?

Oops... sorry Jeffrey, that's the second time I've done that, too!

[MW0SEC]

I had never heard the term 'pantry transmitters' before but assume this must mean a low-powered transmitter to relay signals from FM to MW for the purposes of bringing a vintage radio to life!

I think at some point in the near future medium wave is going to fall silent so I will prob need one of these, they are available ready-made on Amazon,  but what happens when FM is eventually switched off I wonder? DAB radio has it's problems and I am not a fan, I do have a Sony DAB portable in my garage/workshop but when I turn the lights on I lose the signal completely - come the winter and needing to put the lights on during the day I will have to whistle!!

PS I don't know wo Jeremey is?

Sadly, I think you are right about the AM TXs. What I find interesting is (from watching Dave Tipton's restorations) is that AM medium wave seems still well populated in Australia, making AM sets worth some effort. Added to that is the benefit of the wider audio bandwidth employed there. I was always impressed with the quality of MW signals when I lived near Brisbane.