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Saturday, July 21, 2012

Beautiful British Homebrew (with Valves!)

I was rummaging around the junkbox and I found this gem. I probably bought it at the Kempton Park rally in London. I think it is an AM transmitter for VHF. Maybe 6 meters? Or perhaps that British 70 MHz band? What do you guys think? Can anyone estimate the frequency from the size of the coils?

I think the workmanship is beautiful. The technique of putting the tube sockets on a copper clad board is interesting. I wonder why he did that -- obviously he wasn't afraid of metal work. Look at that cable harness work! FB! It's too bad the builder didn't mark it with his call.

Anyone recognize the design? Any idea when this was built? For bonus points: Who built it?

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  1. What is the valve line-up.

    It's probably an old RSGB project.

    Stephen G7VFY.

  2. Wow - looking at the mic input being a belling lee plug you have to be talking about the 60s at the latest. And a Phillips bee hive trimmer as well.
    I'd also hazard that it's on 2M too.

    Ah memories Hi.

  3. It might be a 10w top band transmitter.

    Have you tried powering it up?

    Stephen G7VFY

  4. Dear Bill,

    From the size and style of the coils I think it is a 2M AM transmitter... It sort of looks
    like a HeathKit Tower in some ways.
    take care and have fun
    73 Dave

  5. Bill: HAve you tried a GDO to dip the plate circuit.. will tell you the rough freq.
    73 de paul wa5wcp


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