Let us know how far you get into this checkout procedure. If this voltage is OK then turn on the standby switch and look/listen/smell for any problems. If all tubes light up then check for ≈ -48v on pin 5 of each 6L6. If all the above voltages are OK, then plug in the tubes ONE AT A TIME and verify that each tube lights up. If any of these voltages are messed up the PT is probably shot. Next measure the AC voltages for the two red leads (≈320VAC) and the red/blue lead (≈60VAC). If OK at this point, does the pilot lamp illuminate? If so, the filament winding is probably OK, but measure the 6.3VAC across pins 2 and 7 of a 6L6 socket. KILL THE POWER IMMEDIATELY if you see/smell smoke or hear unusual noises and investigate. I would put the amp in standby mode (open the standby switch) and pull all tubes. You need to check the voltages on the PT. This would create enough heat in the filament winding to melt the insulation as well as the insulation of the HT center tap wire that was twisted together with it. I'm guessing that since the filament circuit is such a high current circuit, there was a short from one side of the filament string to chassis. The melted center taps on the PT need investigating. If the string carries on down the line to pins 4/5 and 9 of all the little tubes then the filament string wiring is probably OK. I can only see the filament string from the PT to the pilot lamp to the two 6L6s and that looks fine. I don't see anything connected to the junction of that 470K/12K voltage divider. I doubt they were trying to 'power' the heaters. Is there anything else I should check? I'd hate to fry a new transformer because of something I've overlooked. It does need updated with a 3 prong cord and rewired properly (+ remove the death cap). Other than that, I'd like to leave it stock as much as possible. I also need to recap all the electro's under the doghouse, bias cap, and board. I'm assuming I need a new power transformer and to rewire the entire heater system. One of the 6L6's also had very loose pins on the tube. I'm not sure if a power tube originally shorted from pin 3 to pin 2 and fried the center tap and then they tried to mod it? Without any tubes in I have continuity between the two sets of heater wires. Someone had the idea of tapping into the 440V control grid pin to create a voltage divider with a 470k/12k which works out to around 10V to power the heaters. The center tap for the heaters is fried/damaged and has damaged the insulation on the 320V center tap. It's original minus a mod that someone did to the heaters. It pretty much sat in a basement for 30 years. The seller said it was his friends and that it was given to him. I bought it as not working but took a gamble on it. I recently acquired a 65 blackface bandmaster. Hello all! I introduced myself yesterday in the welcome area
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