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Old 09-01-2009, 10:21 PM   #1
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67 Bandmaster cap job

Replacing original caps with new Spragues. Two questions (total novice here):
Do the two larger filter caps have to be facing opposite directions to be hooked up in series as shown on schematic? Stupidly pulled them without noting orientation. Also, the kit I purchased from ebay came with 6 smaller caps. Where do these go? This amp has already been recapped, and I can't make out the values on the replacements. The other thing I'm not certain about is that some of the caps that appear to be replacements have three leads, one to ground and one each to various points in the preamp circuits (I think). Could these be replaced with two separate caps each having the same value as the original? Excuse my being a complete tool; any input would be real helpful.
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Old 09-10-2009, 06:17 PM   #2
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sgfable,

The two larger capacitors will be oriented in oposite directions. They are not shown on the layout, but are shown on the schematic, so just follow the schematic.

The smaller capacitors are your cathode bypass capacitors. Follow pins 3 and 8 from your preamp tubes to the board. The ones with three leads are actually two capacitors in a single package with a common negative lead. If you follow pin 3 from the first two preamp tubes, you should run right smack into one of them. If it has already been recapped before, it is quite possible that two separate capacitors were used, which is perfectly acceptable.

Don't worry too much about the capacitor values currently in the amp, just follow the schematic, at least for the smaller ones. Increasing the capacitor values in the power supply from 70uFd to 100uFd is supposed to stiffen the power supply and prevent "ghost" notes, but on my amps recapping made such a dramatic difference I can't say if this made a big difference or not.
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