lnx64
12-15-2013, 09:42 AM
I'm thinking either the CRT is getting a short, or the red bias POT is flakey.
I haven't adjusted it or taken it apart at all lately cause it's been working so well, but lately the red colors flickers a little, gets bright, normal, bright, normal, and it messes with the grayscale tracking too..
Where should I start? It seems completely intermittent, but only seems to do it once it's warmed up.
zenith2134
12-15-2013, 11:49 AM
Hi, my 1978 Sony had this issue upon warmup. It was simply poor solder connections on the video output board(crt neckboard). In fact, I've got a Zenith from about '81 which needed this done as well. Hopefully it isn't the picture tube itself.
lnx64
12-15-2013, 12:05 PM
Hi, my 1978 Sony had this issue upon warmup. It was simply poor solder connections on the video output board(crt neckboard). In fact, I've got a Zenith from about '81 which needed this done as well. Hopefully it isn't the picture tube itself.
Ahh ok, I can deal with that.. Resoldering this TV should be easy.
Bad PC cons on CRT socket board very common on a
lot of sets. If CRT is shorting usually goes very bright
one color with retrace lines. A,little light tapping around
can get it to act up & narrow things down.
73 Zeno:smoke:
TVTim
12-15-2013, 03:34 PM
My Zenith (see avatar) does the same thing once it is on for a few minutes. It will go away if I literally lift the back just a little (1/2 inch or so) and drop it on the table. Works fine after that. Could mine have a similar issue?
My Zenith (see avatar) does the same thing once it is on for a few minutes. It will go away if I literally lift the back just a little (1/2 inch or so) and drop it on the table. Works fine after that. Could mine have a similar issue?
Could be but IIRC the CTR board didnt have much on it.
The control board up front ( color, tint etc) is a double sided
PCB & the feed throughs went intermitant. Again light
tapping around the chassis will usually smoke it out.
Also when you get changes in color turn the color all the way
down & see if the B&W picture is changing also. Narrows things down a lot.
Remember a good color TV has to be a good B&W FIRST !
73 Zeno:smoke: