No, I just wired up the switch and PT to the schematic not thinking about the bias circuit unfortunately. It only gets power when standby is off as its tied to the diode power supply at the moment. Is that too much of an initial load when taken off of standby?
Best standby switch wiring in 2204
Moderators: pompeiisneaks, Colossal
Re: Best standby switch wiring in 2204
Re: Best standby switch wiring in 2204
That loud hum you hear when standby is flipped is the PT and valves gasping / grunting from the severe kicking you’re subjecting them to.
Could you remind me what on earth the point of standby is?
Could you remind me what on earth the point of standby is?
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Re: Best standby switch wiring in 2204
Wire it as I suggested several days ago...
sluckey wrote: ↑Mon Aug 23, 2021 4:16 pm I would use a DPST switch between the PT and diodes just like Marshall did.
https://el34world.com/charts/Schematics ... w_2204.pdf
Re: Best standby switch wiring in 2204
Well I guess i could install some parallel resistors across both poles of the switch. The “soft start switch” from the valve wizard site.
Re: Best standby switch wiring in 2204
Ok i will try it.sluckey wrote: ↑Fri Aug 27, 2021 11:32 pm Wire it as I suggested several days ago...
sluckey wrote: ↑Mon Aug 23, 2021 4:16 pm I would use a DPST switch between the PT and diodes just like Marshall did.
https://el34world.com/charts/Schematics ... w_2204.pdf
Re: Best standby switch wiring in 2204
I changed the bias power supply tap but the sound is still there with the old power tubes. I changed the power tubes to some different el34s and i dont get that sound as much. But when i went to check the bias my bias was 254 milliamps. Not sure i trust this bias probe so i want to install some 1ohm resistors from pins 1-8 to ground to check the bias easier. The bias voltage on pin 5 of both sockets is -42v with my bias pot at half. The 5.6k grid resistors both are at 5.49k the 1k screens measured both 985ohms.
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I just put 2 100k resistors across the standby switch contacts and the amp seems to like it. No pop, no weird inrush noise turning standby on or off even at high gain and volume levels. My bias probe has to be messed up, it did the same thing with my other amp with the crazy high bias reading. So ill be installing some bias test points shortly. Ive wanted to do that anyways. I appreciate the help here, thanks.
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I just put 2 100k resistors across the standby switch contacts and the amp seems to like it. No pop, no weird inrush noise turning standby on or off even at high gain and volume levels. My bias probe has to be messed up, it did the same thing with my other amp with the crazy high bias reading. So ill be installing some bias test points shortly. Ive wanted to do that anyways. I appreciate the help here, thanks.