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Old 11-20-2011, 02:08 AM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
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The first challenge was finding the correct schematic. At first I was using the scanned Riders vol 6 available from the ETF.

I quickly found differences though. For example there are 3 couplates in this set but none are shown in Riders.


Also, these power resistors differ from Riders and I found a germanium diode detector while Riders shows a 6AL5.


I did some research and it seems they made at least 22 production runs of this set
I discovered a faint 'RUN 14' stamped on the back and tracked it down in a Wallace Telaide.

Here's an explanation of those power resistors.


I restuffed the electrolytics and replaced most of the old caps and out of spec resistors.


The first power up treated me to some nice audio for about 5 seconds then silence and no raster or HV.

I just started checking the tubes and found a 12AV7 in the 12AU7 socket. Also this "TEL-A-SAVE" 6AC7 video output tube has a cathode short and shows no emission on my Hickok.
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Last edited by bandersen; 11-20-2011 at 02:16 AM.
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