Quote:
Originally Posted by Console User
The RCA Console TV I have is a 1985 Color Trax 2000. It has the Chasis CTC131 A. The Model of this particular set is GLR2538P.
I was wondering if anyone would have a Schematic on this Chasis to locate the adjustment for the Horizontal and Vertical? It needs adjusting.
Thanks.
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For the CTC131 chassis, not much usually went bad beyond the obvious.
As to the vertical, C501 and C510 both were commonly replaced caps in the vertical - a faulty C501 causes shrinkage from the top, and a faulty C510 would cause retrace lines at the top of the pix due to vertical foldover. We swapped them out as a callback preventer.
U700 (the Chroma/Luminance/Video chip) would also cause changing colors as the set warmed up - most noticeably the red. RCA issued a Goldenrod aimed at chasing down other parts that could cause problems, to avoid changing out a good U700. In one test, they had you monitor pin 27 of U700 until the problem appeared - most often it would change to a lower than 5V value if U700 was bad, else some other part was bad. Among the culprits:
R5076 on the CRT board - intermittent opens, cause loss of red in pix.
R5074 on the CRT board - changing green levels, likely intermittent.
Put a scope on all the supplies - the 16.5 volt source filter cap would open up, and cause all sorts of troubles - hum, wavy pix, lines in the picture (also could be the tuner/MST...) and no color.
The CTC131 and 132 were great chassis, just had to weed out a few components...and yes, the CRT is probably tired. Only recourse there is a replacement.