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Philco 90 grid voltage and RF choke
#3

(04-10-2016, 07:48 PM)morzh Wrote:  David

What grid Vs are negative? The 45's are supposed to be.
No the choke won't change grid Vs and the detector works without it.

You need to be more posts exact in your statements.


Sorry for the vague post.  I am new to the hobby and to the forum.  I purchased this iconic model 90 and was hoping to restore it myself.  I am having trouble tracking down the cause of the abnormal grid voltages.  I attached a chart of the voltages from the service bulletin.  The values in red are the abnormal readings from my set.  The rest of the readings matched the bulletin.  Measurements are from ground to the tube pin.
Thank you again!  I really hope to get the set playing again.


Attached Files
.pdf Philco Model 90 PP45s Voltages.pdf Size: 155.85 KB  Downloads: 368


Messages In This Thread
Philco 90 grid voltage and RF choke - by Davidra - 04-10-2016, 02:26 PM
RE: Philco 90 grid voltage and RF choke - by Davidra - 04-10-2016, 10:55 PM



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