There’s an old joke that all you need to fix TVs is a cheater, a heater, and a meter. If you don’t remember, a cheater was a cord to override the interlock on TVs so you could turn them on with the back removed. Of course, in real life, pro repair techs always had better equipment. In 1939 that might have meant the Supreme Vedolyzer which combined a meter, a ‘scope, and a wavemeter all in one device. [Mr Carlson] acquired one that was in fair shape and made a few videos (see below) of the teardown and restoration.

[Mr Carlson] wasn’t restoring this as an art project, by the way. He plans on using it, so he was less concerned with authenticity and more worried about usability. That led him to do things like remove the input jacks and replace them with BNCs. The video series is a bit of a time investment. Part one is about 82 minutes long! But if you are interested in old gear, this is a chance to peer inside an unusual specimen.

If you don’t watch anything else, though, you should have a look at the rebuilt center tube assembly. There were quite a few old components in that module and some had already been replaced by someone else. The before picture (left) and the after picture (right) shows off [Carlson’s] skills nicely.

You might wonder why he might want to use a piece of antique gear like this when he obviously has state-of-the-art equipment at his disposal. We get it. Just as you see people making soap or lace using old fashioned methods, it has to be satisfying on some level to use old test gear to restore old radios.

Supreme, by the way, was an instrument company from Greenwood, Mississippi. They made a lot of gear including an audolyzer (aimed at radio servicing). That web site, by the way, has scans of the user’s manual and other documents related to the instrument.

In 1939 engineers probably were not servicing a lot of TVs — RCA introduced American TV that same year at the World’s Fair — so this might have been a risky investment for most service centers. The history of TV around that time is pretty interesting. Our favorite pro TV service tool, though, was the later TV Analyst. This was a little TV station that could send an errant TV any signal you needed to isolate the problem.

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Source:: Hackaday