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![]() hillbilly3302 wrote: looking for a 1N2637.... its the solid state replacement for a 866 tube k5drc The Gonset GSB 101 uses the same setup - 2 866's & 4 811's I replaced the 866's with series strings of 1N5408's, and added a turn on delay, because you get a pretty good surge with the solid state rectifiers. Power to the HV xformer is fed through a resistor for about 5 seconds, then a relay transfers and shorts out the resistor. You don't need 3 amp diodes (1N5408), but I was building another supply at the same time and had them on hand. The Gonset uses a string of capacitors, fed through a 5 - 50 swinging choke. Each cap has a bleeder across it, as I recall, rather than a single bleeder. If the Warrior uses the same style choke input filter, the choke could be bad. Mine was missing - in fact the previous owner had messed with it and substituted something different, which he did not bolt down. I bought the thing at a scrap yard for $20.00, and all the tubes had been smashed by that "choke". I guess it really was a swinging choke! The crying shame is that the original problem was a bad solder joint to the caps. I surmise that the previous owner mis-diagnosed the problem as a bad choke and tried substituting various filament transformers for the choke. In any event, that choke takes a helluva surge when the solid state diodes suddenly conduct upon power on. So you may want to include a soft start circuit, once you diagnose your hum problem. While you're at it, check the bleeder resistor(s) and replace as needed. I'd recommend using 2 parallel resistors to replace each bleeder in your Warrior, if you have the room. Use the same wattage and twice the resistance of the bleeder you are replacing for each new resistor, effectively doubling the wattage. Also, you should form the capacitor(s). I'm assuming the replacement cap has been on the shelf for a long time. I formed mine by powering the amp from a variac, and over the course of 24 hours raised the voltage in 10 volt increments every couple of hours until I went from 10 volts to 120. Good luck - it's nice to get these old beasts up to snuff. |
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