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Philco Model 20 distortion
Chuck Schwark
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#4

04-16-2012, 02:18 PM
(04-16-2012, 01:42 PM)morzh Wrote:  The mica cap is on the last 24's plate (detector). A 250pF.

Be sure ALL resistors in the set are within a 20% tolerance of their nominal values. I'll bet you have a grid bias problem on the 71A's or insufficient plate or screen voltage(s) somewhere. Carbon comp resistors usually go way up in value with age. Also check the BC resistor sections for correct values.

Chuck
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Messages In This Thread
Philco Model 20 distortion - by 93foxconvert - 04-15-2012, 11:34 PM
RE: Philco Model 20 distortion - by 7estatdef - 04-16-2012, 09:17 AM
RE: Philco Model 20 distortion - by morzh - 04-16-2012, 01:42 PM
RE: Philco Model 20 distortion - by Chuck Schwark - 04-16-2012, 02:18 PM
RE: Philco Model 20 distortion - by morzh - 04-16-2012, 04:19 PM
RE: Philco Model 20 distortion - by 93foxconvert - 05-06-2012, 01:21 PM



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