Egnator Renegade 65

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Hello, I have a Egnator Renegade 65 on my bench that will only pass signal out of the poweramp section. The power tubes are lit up and the power section works as it does pass audio . The preamp tubes are not lit up . The schematic is quite vage in showing where my B+ comes from to power the preamp tubes. I should have around 450 volts on the preamp tubes and I have 0 volts. I hope its not the xformer. If anyone has an idea please contact me. Thanks.
 
Get the heaters lit first, you might find that the reason they are dark is the same reason for no voltage. Just a thought, but both those power supplies come into the preamp through a connector, no?

My schematic shows t preamp tube B+ coming from QC1 in the power supply, so an open resistor there could kill the suply. But check the connector idea first.
 
I do have 450 volts on one of the pins on the pre amp tubes But I'm still missing my 12 v for the filiment voltage. Where does it come from and where can i find it. If come straight out of xformer , customer may have to buy a new xformer . Schematic is very vage. Thanks for your help Enzo.
 
I got it fixed . It was the low voltage bridge rectifier. Traced the loss of 12 volt filiment voltage all the way back to that device . What throws me tho is that the filliment voltage may in DC . I do not know for sure but thats weird if it is . its mostly in ac volts in most amps. Thanks one and all for your help.
 

PRR

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When rectifiers were costly, heaters were all AC.

I think a guitar amp "should" hum, though not enough to notice.

Low-hum AC heat kinda needs twisted wiring. You can't do that on a PCB.

*Well filtered* DC hums less. As the price of an Ampere of low-volt rectification and filtering fell, more and more mass-market amps have been using DC heat so heater feeds can be run on the PCB.
 
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