Pirate radio AM transmitter with PF86 in oscillator,  PCF80 in cathode follower and driver, PL 36 in driver and PL 509 / PL 519 in output stage. This transmitter is completely done without transformers. Only one transformer is used for modulation. In this version I used about 850 V in PL 509 plate. Finally I made 1500V power supply .It’s amplitude modulated on second grid of PL 509. I used stabilized power supply for G2, to avoid “vibrations” and to achieve better modulation quality. G2 voltage can be very fine regulated, so you can adjust power very close to max dissipation limits.

With this pirate radio transmitter and revised receiver RR230 with preselector, I spent a lot of time in the period from 1989 until 1992. I used 83 meters long longwire antenna at height of approximately 20 meters. As modulator I used an amplifier with two EL84 (6BQ5) in a push-pull connection, ECC83 (12AX7) as cathodyne phase inverter, EF86 (6267) as line preamp and ECC81 (12AT7) as microphone preamp in connection with amplitude limiter.

My call sign in that period was Columbia, Pancevo, 73 to all people I talked to!!!

This Post Has 6 Comments

  1. white air max

    Do you have any video of that? I’d want to find out more details.

  2. Per

    Nice to know someone else used the PL519 as PA for transmitters.

    Maybe we have talked sometime, but I don’t remember.

    Call sign : Nummer 05

  3. Dragorad

    Radio sam kao radio ZLATIBOR sa predajnikom u izlaznom stepenu 2X GU81 napon na anodi 2400volti,antena 42metra na frekvenciji 1750Khz.

    1. tubes.rs

      Pozdrav Zlatibore, bilo lepo krajem 80ih i pocetkom 90ih na srednjim talasima …

  4. Dragan

    Zlatibor ponovo na srednjim tranzistorski eksajter+2XGU81 anode 3000v subotom 1730khz javi te se pozz 73.

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