02-18-2013, 05:48 PM
Sneak low impedance leakage in osc tube socket or in the bandswitch wafer(s)....crud/dust/?? Clean with Q-tip with isopropyl alcohol, NOT dexoit which leaves behind oily anti-corrode residue. Maybe hard to see or get at both side of each wafer and between stationary contact lugs? I assume you have checked for and eliminated the Philco Coil Greenies and the osc tube is good.
Maybe a marginal osc tube? Tried a swap? You'd think AM would oscillate if SW bands do, somewhat.
'tis curious...
Chuck
Maybe a marginal osc tube? Tried a swap? You'd think AM would oscillate if SW bands do, somewhat.
'tis curious...
Chuck
Chuck Schwark,
The Philco Repair Bench
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