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Philco 20 restoration state: need the voltage chart
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1. All 5 wire-wound resistors, 50K, 100K, 250K, 500K have run away to the values that are anywhere 30-100% up.
Wow. Granted, I have no experience with these that are 80 years old but the resistors I did not expect to behave like so.

Need to buy those.


2. Also, the tapped resistor last section (1-2) of 1.4K that ties the 71A filament's Power Xfmr winding center-tap to all other Xfmr centertaps was just opened.
I even think I know why - the output stage probably smoked, as the output audio Xfmr primary, one half, was fried, and so was one of the tubes. There was something catastrophic, so the current probably burned that 1.5Kohm section.

Once I put an external 1.4K resistor there, the speaker came alive, and I clearly hear a reasonably loud scratch when I rotate the volume (the antenna attenuator) var. resistor.

I wonder what else's in stock for me, but I will start with resistors.

I want to buy "authentic" parts, so what do you tfhink of "Philcorepairbench.com"?

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


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Re: Philco 20 restoration state: need the voltage chart - by morzh - 10-26-2011, 08:32 PM



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