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Old 01-03-2016, 06:08 PM
Eric H's Avatar
Eric H Eric H is offline
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Join Date: Jun 2002
Location: So. Calif
Posts: 11,565
I'm going to declare this one done!

I thought I was done a couple days ago but then I noticed a little vertical shrinkage and flagging at the top of the screen, increasing the AC voltage stopped all this.

I had noticed the B+ was about 20 volts low because the Selenium Rectifiers were getting tired, I was going to let it slide until these problems popped up.

With some help from the people over at the A.R.F. I ripped them out and replaced them with Diodes, after doing that I had to increase the size of the resistor feeding them because the B+ was 20 volts too high, then I had to install some snubber diodes across the caps to stop the hum bars caused by the diodes, it was a bit of work but after getting it all worked out the set looks great!

According the the 1956 Sears catalog, this was Sears Best portable, it's a cheap, series string set with a fairly low tube count but it works as well or better as some of the Deluxe RCA Portables I've worked on, and it's a heck of a lot easier to work on!
Attached Images
File Type: jpg I-wonder-if-you-wonder.jpg (13.0 KB, 21 views)
File Type: jpg Silvertone.jpg (35.2 KB, 26 views)
File Type: jpg 1956-Sears-Christmas-Book-.jpg (83.5 KB, 16 views)
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