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An Introduction and a Philco 90 issue.
Steve Davis
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#44

11-27-2021, 01:05 PM
I'm not sure what is going on here. With the speaker unplugged we are reading the resistance of resistors 49 and 50. with the speaker plugged in we seem to be reading the speaker field coil but I don't understand how. The number 4 wire connects to the upper end of the coil but the lower end of the coil should nowhere be connected to chassis ground, that is why I suspected a shorted filter cap. Maybe someone will jump in and help us here. CALLING TERRY! ....... ANYONE!
For now let's move to the terminal 3 wire. We have zero ohms here, should be infinity. Looking at the schematic, you can see this wire connects only to the cathodes of several tubes and should not have any connection to chassis ground. Trace this circuit looking for an error.

Steve
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An Introduction and a Philco 90 issue. - by cknob - 11-23-2021, 09:20 PM
RE: An Introduction and a Philco 90 issue. - by Steve Davis - 11-27-2021, 01:05 PM



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