I've just finished the build last week, after finally hooking up a couple of BBQ 10's in a cabinet. I noticed that I had mixed up the high power layout with the 120. Fixed that. I also didn't have pin 3 of V5 (el84) connected. I thought the wire in the layout just went over the tube socket. I fixed that.
No output.
The voltage readings are way out of wack. I am seeing almost no drop at the cathodes....
Readings: (all in DC, measured from ground)
______1____2______3____4___5_____6___7_____8__
V1.....320...............214.........................320...............212...
V2.....264...............220.........................327...............262
V3.....293...............233.........................339...............225
V4...........................16,0................................332..............
V5...........................16,0................................360..............
V6.............................................................................350
V7......288..............215.........................320................214
All the tubes are aglow; the rectifier looks normal, el84s are bright and really hot and the 12ax7s are faintly charged.
I measure the voltages coming off the series resistor drops:
R25=116V, R26=322v, R27=302v, R28=330v, R42=330v
The only one that is really performing is R25, pin7 at V4 and V5 still out there.
The filter caps are all reading good, all open.
Found a bit of crackle when flicking the Crunch/Munch switch and probing the phase inverter. When I turn the amp off it makes almost a sound that replicates the effect when 2 jedi are incased in a light saber battle.
Any ideas? Where should I look?..
Stephen, anybody, please help..
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