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Old 12-20-2024, 12:52 PM
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jhalphen jhalphen is offline
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Join Date: Feb 2007
Location: Paris, France
Posts: 592
Hi to all,
Hi Ruru,

OK, loss of V scan, although depressing, should be fixable.
Please turn down brightness to just visible, an overbright single line can burn-in the CRT's phosphor.

some ideas :
contact RonL here, he may not have received your request :
https://antiqueradios.com/forums/vie...2378&start=180

Please post exact & full TV model on chassis sticker or metal plate or rear of TV. Sometimes, it's just a series of letters & numbers inked somewhere on the metal chassis.
RCA B&W TVs of the 50s use probably quite identical schematics in USA & Canada, maybe we can find the US equivalent on the ETF Museum (Early Television Museum) schematics database (see below).

All RCA post-WWII B&W ETF schematics are here, includes some Canadian models (scroll down).
Search is by chassis #, be sure you have it for your TV :
https://www.earlytelevision.org/tv_s...grams_rca.html

As you have already "recapped waxies, etc.) think of simple things : corroded tube pins or socket, socket contact not gripping well tube pin, noisy/cut track inside V Height pot or Linearity pot.

Do you have an oscilloscope ?
if so, you could trace V oscillator operation, then follow the signal to V output tube.

The V section of a B&W set is quite simple: Sync separator, V oscillator, V output tube. If the tube location sticker is still present, it's easy to find the 2 or 3 responsible.

A word of caution ! if the TV is "Hot" (transformerless), you will need an isolation transformer powering the TV to safely connect a Scope.

keep us informed of progress or difficulties...

Best Regards
jhalphen
Paris/France

PS : i suggest you change the name of the thread to "Repair of Canadian RCA B&W TV chassis xxx (or model xxx).
it will greatly help future searchers & collectors.

Last edited by jhalphen; 12-20-2024 at 01:17 PM.
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