Zenith TVs
 

I was curious if anyone might be able to reference a Zenith SY2551S
problem. The picture is purple in color, meaning a failure in the green
circuit. I am gathering the part is blown up, so the part number would be
most helpful. Is there a common culprit for this failure on this chassis?

Additionally, I am troubleshooting two SL7573W with similar symptoms
(probably bad filter caps). Does anyone possibly have a schematic for part
values?

Thanks!

Zenith TVs
 

In general, with Zeniths, check the three small signal trasistors by
the jungle IC.
2N3906, & the three large video drivers on the CRT board, on the pix
tube neck.
Do this...before you boost/rejuvinate the pix tube. Thetube MAY be ok.
Hope this
helps, Dani.



cz wrote:
I was curious if anyone might be able to reference a Zenith SY2551S
problem. The picture is purple in color, meaning a failure in the green
circuit. I am gathering the part is blown up, so the part number would be
most helpful. Is there a common culprit for this failure on this chassis?

Additionally, I am troubleshooting two SL7573W with similar symptoms
(probably bad filter caps). Does anyone possibly have a schematic for part
values?

Thanks!

Zenith TVs
 

You should strongly suspect the picture tube if the tv sets were made
between 1993 and 1997. It is a simple matter to ground each cathode on
the crt with a 1K ohm 5 watt resistor to check for any kind of decent
output from each color. You can also carefully swap the red and green
drive on the crt socket with a careful removal of solder and addition
of jumpers to confirm or deny that it is the picture tube.

The later models sometimes would have a 2n3906 next to the jungle ic
that would go bad, typically on the Z line chassis.

The 'L' and 'Y' models almost all had bad picture tubes by now. The
common culprit is the picture tube. Many times when it would fail it
would also take out the power supply.