09-21-2008, 10:05 PM
Ed
If your 70 (without AVC) or 90 (using two Type 45 output tubes) use the dual type volume control (250 ohms and 5000 ohms), AFAIK, all of these are wirewound and may be safely cleaned with any good contact cleaner.
If your 90 is a "mid" production (1-47) or "late" production (2-47), then it uses a 500K pot that may, or may not, have the resistance on a cardboard-like backing. I honestly do not remember the exact construction of these at this time, although I seem to recall cleaning them with no ill effects.
If your 70 (without AVC) or 90 (using two Type 45 output tubes) use the dual type volume control (250 ohms and 5000 ohms), AFAIK, all of these are wirewound and may be safely cleaned with any good contact cleaner.
If your 90 is a "mid" production (1-47) or "late" production (2-47), then it uses a 500K pot that may, or may not, have the resistance on a cardboard-like backing. I honestly do not remember the exact construction of these at this time, although I seem to recall cleaning them with no ill effects.
--
Ron Ramirez
Ferdinand IN
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