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Old 04-07-2020, 03:08 PM
Donj Donj is offline
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Join Date: Feb 2019
Posts: 28
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Finally got started on this beast. Being a Canadian model, it is set up for 25 cycle operation and has a separate chassis for the low voltage power supply. It is just a little thing .

First thing I noticed was that the two rectifier tubes were 5R4-GY rather than 5V4G as shown on the chart. I don't expect this is a problem. One of the two tubes tested dead. Digging a bit deeper, I found that one of the two 30 mfd filter capacitors associated with the dead tube displayed a pretty much dead short. The date code on the caps indicates that they are the originals. All windings on the power transformer and choke associated with the bad capacitor ohmed out fine, so it doesn't appear that the problem extended beyond the dead tube. Hopefully, this failure was the reason the set was retired many years ago.
Anyhow, will restuff the electrolytics and replace the few paper/wax caps and a few resistors in this chassis and that should take care of the low voltage chassis.Then on to the main one.
Since I have one dead rectifier tube, should I replace with the 5R4-GY as was there, or should replace with 2 5V4Gs as called for in the tube chart??
Attached Images
File Type: jpg pswtsm.JPG (41.4 KB, 42 views)
File Type: jpg badcapsm.jpg (48.1 KB, 35 views)
File Type: jpg pscapssm.JPG (49.3 KB, 30 views)
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