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City: Chicago, IL
I believe I found the problem - or at least one significant problem. No plate voltage on the RF tube!
Looks like we have an open primary on the transformer between the RF and 1st detector stages.
I'll dig it out for a closer examination. I may just swap it with the one from my parts chassis.
Also, it seems the voltage chart in the upper right cannot be right.
One issue is that is shows different voltage for the RF and IF cathodes even though they are connected together.
A much bigger issue is that it shows 20 volts on the 1st AF cathode even though it's grounded!
[Image: https://live.staticflickr.com/65535/5163...98c2_b.jpg]
(This post was last modified: 10-27-2021, 05:45 PM by Bob Andersen.)
Messages In This Thread
RE: Philco 90 restoration - by Bob Andersen - 10-27-2021, 05:44 PM
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