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5E3P Build problem

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  • 5E3P Build problem

    So I built this 5E3P with some old organ irons. First with a 440-0-440, and then switched out to a 380-0-380. Tried 2 different OT's as well. Checked and rechecked the wiring. And when I plug in all I get is a very faint distorted sound with a squeal mixed in and only when the tone is turned up. Turn the tone to 0 and no sound at all. These PT's do not have a bias tap so I did the circuit attached (which I'm wondering may be the problem). I went to try it with the bias circuit disconnected to see if that was it but it drove the power tubes too hot so I never got the chance to plug in. I have tried different tubes out of a working amp and did the same. Tried a 5U4G rectifier too. So before I go and buy new irons I thought I would run it by you guys and have you look at these voltages and maybe give me some suggestions. Here are the voltages with the 380-0-380 in.
    V1 (12AX7)
    1> 245v
    2> 0
    3> 1.7v
    6> 237v
    7> 58v
    8> 1.7v
    V2 (12AX7)
    1> 224v
    2> -2.15v
    3> .9v
    6> 266v
    7> 58v
    8> 93v
    V3 (6L6GC)
    3> 474v
    4> 447v
    5> -76v
    6> -76v
    V4 (6L6GC)
    3> 473v
    4> 447v
    5> -76v
    6> -76v
    V5 (5AR4)
    4&6> 380
    2&8> 493
    Attached Files

  • #2
    Pin 7 on V1 should be 0 volts but oddly you show a nominal 1.7v on the cathode which sounds right.
    The -2.15 v on pin 2 of V2 is not right. The bias voltage on pin 5 of the output tubes sounds too cold.

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