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Old 30th Oct 2019, 7:54 pm   #24
Join Date: Nov 2016
Location: Budapest, Hungary
Posts: 354
Default Re: Vintage Radio and Phonograph cutter schematic

hey Lawrence and All,

I am getting some trouble with this old readings on some of the tubes compared to the chart Lawrence gave us in the previous post....

also, I am having 105 VAC in the chassis with some significant hum

All the drifted resistors are replaced and the cap's too one by one.

Where I am getting the off readings are the two 6SJ7's and the 6SF7 and the 6SA7. Before these tubes, the readings are spot on. So the rectifier, the 6v6 and the 6SC7 reads nearly spot on.

I have no histry of these tubes as it came with this old unit..... should I start swapping them out with other tubes and see the results?

I am not sure where the 105 VAC is coming into the chassis...

PS: Slight correction, i did not change the power filter capacitor as read spot on 16+16 UF and very low Ohms.
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Last edited by Levente; 30th Oct 2019 at 8:02 pm. Reason: missing doc
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