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Originally Posted by roundscreen
On the manual you sent me that resistor shows R165 Someone wrote omit on it in ink. -22v is low.
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The grid control of V104 (6CB5) is connected over R601 with the brightness control of the set (R101A). This is important to know.
Last night I have changed R601 (470K) with a 900K resistor, horiz. current was only 170-180ma, grid of 6CB5 has -35v to -39v. This seems OK, but brightness is overloading, at minimum brightness control there is full brightness and picture width changes enormously with brightness adjusting.
Later I analysed the horiz. oscillator section. I have already noted that R165 at the grid of 6CB5 is missing. But this was wrong assumption.
They have moved R165 on the Hor. Oscillator Assembly plate (PW 600). "Ground" of R165 is the grid of the 2nd. triode of V601 (6CG7). R165 can switched off/on by a cable link on the printed circuit. (See the blue colored part of the schematics here). I have changed the location of R165 according to the origin schematics of the manual (yellow colored part). But horiz. current exceeded 230ma and grid of 6CB5 has -20v. This was the wrong way. I have restored the origin circuits of the set (with R165 at grid of V601, blue colored part).
At the 2nd. grid of V601 I measured -40v instead of -68v (or maybe -88v, it is not clear printed in the manual). I assume that the oscillator doesn't provide a full amplidute sine wave.