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Working on a '72 silverface 100 watt Twin Reverb. Guy says he bought it and brought it to a gig and IT WASN'T LOUD ENOUGH! 
Looks to be all original and untouched. I popped the doghouse and two of the caps were popped, with copious amounts of splooge in the cover. He agrees that is the first order of business, then I found the two node resistors were shot, one was burnt and cracked in half, the other had drifted from 10K to 18.5K. So I remedied that, did the bias and cathode caps, converted to blackface bias circuit, as well as a couple other little things and am now ready to fire it up.
It looks good on the limiter, voltages looked low, but I don't worry because it's on the limiter. I power it up direct, and I still have low voltages. My secondary is 690vac, but my B+ is 324vdc in standby and rises to 376vdc switched on. The schematic shows a 630v secondary and B+ at 415v on and 450v standby. What could cause this opposite and lesser outcome? The transformer passes the neon test. The diodes check good in circuit, and the voltages look the same side to side down the line. I confirmed it is the correct transformer.
Could I have a bad reservoir cap? I rule out the node filters because the B+ is low with standby open.
http://www.thetubestore.com/lib/thet...-Schematic.pdf
Looks to be all original and untouched. I popped the doghouse and two of the caps were popped, with copious amounts of splooge in the cover. He agrees that is the first order of business, then I found the two node resistors were shot, one was burnt and cracked in half, the other had drifted from 10K to 18.5K. So I remedied that, did the bias and cathode caps, converted to blackface bias circuit, as well as a couple other little things and am now ready to fire it up.It looks good on the limiter, voltages looked low, but I don't worry because it's on the limiter. I power it up direct, and I still have low voltages. My secondary is 690vac, but my B+ is 324vdc in standby and rises to 376vdc switched on. The schematic shows a 630v secondary and B+ at 415v on and 450v standby. What could cause this opposite and lesser outcome? The transformer passes the neon test. The diodes check good in circuit, and the voltages look the same side to side down the line. I confirmed it is the correct transformer.
Could I have a bad reservoir cap? I rule out the node filters because the B+ is low with standby open.
http://www.thetubestore.com/lib/thet...-Schematic.pdf
I forgot I lifted one of the reservoir caps to check something and neglected to solder it back!
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