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Motorboating question for the experts
Arran
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Posts: 4,703
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City: Sandwick, BC, CA
#2

01-12-2013, 01:06 AM
One of the most common causes of motorboating in an AC/DC radio is an open bypass cap, usually a .22 microfarad one between the chassis and the B- bus. In the case of Philcos this is the big paper cap connected in series with a choke, sometimes made out of wire wrapped around the body of the capacitor. It could also be an open output filter capacitor, or rather the B- connection to same.
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Arran
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RE: Motorboating question for the experts - by Arran - 01-12-2013, 01:06 AM



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  1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration