DG’s Practical Notes, R#4 TRF receiver kit of the 1930s from France [v2] «Arena» dial

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  • เผยแพร่เมื่อ 19 พ.ย. 2024

ความคิดเห็น • 4

  • @appunti2
    @appunti2  4 หลายเดือนก่อน +1

    This is a revised version of this radio project, three years after the first restoration attempt. Even if it is embarrassing, I kept and simply extended the original video: I hope that my mistakes and naivety could be helpful to others.

  • @johnwest7993
    @johnwest7993 4 หลายเดือนก่อน +1

    I like TRF radios. I have one I built for a WWVB receiver on 60 kHz, and an old Arborphone 27. They need a long antenna, and are a pretty unsatisfactory radio, but I still like them for their simplicity.

    • @appunti2
      @appunti2  4 หลายเดือนก่อน +1

      Hello. Regarding the beauty of TRF radio, I can agree with you, but I wish I could have the place for a long antenna, as well as a quiet electrical environment. 🙂
      As for the Arborphone 27, you have a very beautiful radio!
      Thank you for your comment. 🙂

    • @johnwest7993
      @johnwest7993 4 หลายเดือนก่อน

      @@appunti2, you might try building a 1 or 2 turn, 4 foot diameter, tunable mag-loop using aluminum roof flashing material to get the highest Q possible and lower the noise. There are lots of videos about different versions on TH-cam. Mine works in a horribly noisy environment. (I have heavy power-lines right outside my bedroom and living-room windows, so only about 15 feet from my indoor antenna.) Add a cheap pre-amp to get the signal level up and you'll be in business. Tuning and positioning to minimize noise is inconvenient, but that's the trade-off to have a compact antenna that will work in your environment. Basically the tunable loop and pre-amp act as a first TRF stage, and a high Q (for a very narrow bandwidth,) small loop is the way to cut out noise. Such a loop with a good tuning capacitor can have such a high Q on lower frequencies that the antenna's bandwidth on the 160 meter ham band just above the AM broadcast band is less than the full bandwidth used by a SSB signal. That removes a whole lot of noise before it even gets to the receiver.