WTF is this? Tru Tone Model 300A

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  • petehall347
    Badcaps Legend
    • Jan 2015
    • 4426
    • United Kingdom

    #21
    Re: WTF is this? Tru Tone Model 300A

    try searching for the valve numbers 35Z5 -12SJ7 50L6 and see if it matches any schematics .

    Comment

    • eccerr0r
      Solder Sloth
      • Nov 2012
      • 8701
      • USA

      #22
      Re: WTF is this? Tru Tone Model 300A

      Looking at the guts, I think this must be some sort of transmitter. Its ΒΌ" jack feeds to a pot that's capacitively coupled to the grid of the 12SJ7 grid.

      Likewise the 50L6 plate seems to be coupled to coil and the pigtail "antenna" output. It's too simple to be anything other than AM as far as I can tell. Drat, still looking for a cheap SSB transmitter.

      Next is to somehow figure out the frequency... if only I had a spectrum analyzer, that'd make it real easy...

      Comment

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