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5G9 Trouble Shooting

Discussion in 'Shock Brother's DIY Amps' started by jmp81sc, Sep 11, 2020.

  1. Dan_Pomykalski

    Dan_Pomykalski Tele-Meister

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    I haven’t read through the entire thread yet, but do you still have a shares cathode resistor and cap on V1 (for channel interaction)?
     
  2. D'tar

    D'tar Friend of Leo's

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    It appears to be shared...

    upload_2020-9-17_14-59-24.png
     
  3. jmp81sc

    jmp81sc Tele-Meister

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    Dtar is correct v1 cathode is shared
     
  4. andrewRneumann

    andrewRneumann Tele-Holic

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    Did anyone comment on these grid bias voltages? They look strange to me. Expected both to be about 29V if the cathodes are 30.6V.

    B9549DD1-B6E7-4D9C-8DD9-F8405EF97BBF.jpeg
     
    D'tar likes this.
  5. D'tar

    D'tar Friend of Leo's

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    It must be wacky PI week!
     
  6. jmp81sc

    jmp81sc Tele-Meister

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    Hi everyone,
    I rechecked all of my voltages this morning, and everything is as it should be. The voltages coming off of the grid for the phase inverter now measure 9.1 and 10.2 volts, green arrows in above post. Probably a measuring error on my part the first time.

    The amp sounds fantastic and everything works as expected with the trem foot pedal in plugged in. I still don't hear much interaction between the volume controls however.

    I don't know why it matters if the foot switch is inserted, but it is working like this, so I am going to live with it as is. It doesn't make sense to me why it would matter so I have been chasing my tail trying to figure it out.

    I am just going to chalk this one up to the electron gods wanting the foot switch plugged in.

    thanks everyone
    John
     
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