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Philco 20 - variable capacitor tuning
#10

I cleaned the '24' grid contacts (they were dirty but not corroded) and sprayed deoxit.  Then i decided to try and align at 140/1400 and the sound was just about as loud as you could ever want,  but no signal without my finger on the center variable condenser nut. 

I checked the plate voltage and it was 255 and conformed with the schematic - although i usually play my radios at 100 via the variac.  I don't want to burn tubes on these so i'm a little protective.

last, i touched my fluke mulimeter to the center coil at the lug from the grid (same as from the tuning condenser) and it plays loud and clear.

"All roads" point to that coil but i don't know why my alignment is not impacted.  Thanks for pointing to this - now i know which coil. Rich


Messages In This Thread
Philco Model 20 schematic by Ron? - by winston763 - 02-19-2017, 01:56 AM
RE: Philco 20 - variable capacitor tuning - by winston763 - 02-20-2017, 03:39 PM
RE: Philco Model 20 schematic by Ron? - by sam - 02-20-2017, 12:21 PM



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