1970s Zenith Console - Troubleshooting

[ThePlague]

If there is a burn mark on the CRT screen, I cannot see it. The burn must be quite small, or else it is located in a corner of the screen where most people would not see it unless they were looking for it, and I zoomed in on the image to have a closer look at the set; I still could not see any evidence of a letterbox burn mark anywhere on the screen. These marks can appear on older TVs' CRTs if the horizontal or vertical sweep is not working properly; when the vertical sweep failed in CRT sets, and the set owner did not turn down the brightness control immediately, the line across the width of the tube could and often did burn a mark in that area--ruining the tube, of course.

Burn marks at the sides of the CRT screen can also occur if a 16:9 image is viewed on an older TV, since the picture will not fill the screen, as was mentioned. This type of screen damage can also occur in flat-screen HDTVs if a 4:3 image is viewed with the zoom control set incorrectly. However, if a 16:9 image is viewed with the zoom set for 4:3 aspect ratio, black bars will appear at either side of the screen; this can and likely will cause permanent burn marks (from the LEDs or backlight) if the picture is either viewed with excessive brightness or for an extended period of time.

I have attached closer pictures of the screen that hopefully provide a better view of the burn-in.


I just went to fire up the TV to verify that it was indeed still dead, but to my surprise it was not. Upon power up the static audio came in, but I did not hear any HV whine kick in. After about 5 seconds, the breaker blew. Resetting the breaker produced the same results. Due to the age of this unit and my desire to daily drive it, it may just be best to fully recap this system (including the safety caps) and begin troubleshooting afterwards. I'll have to pull the chassis out and make a list.

The black looks like static attracted dust from normal use. Rubbing alcohol should clean it, Goof Off will clean what alcohol misses.

That is good to hear!

[zeno]

Best to recap after you get the HV up

Oil cap. Lift one end & try again. If its bad you will get a raster
but it will pulsate.

Sockets burn inside at focus pin. Almost a Zeniths from the 70's
use the same part but have different lead lengths & connectors.
Dont remember P# but format is 78-####-##.

Cant see the HV area but loosen the tripler & HV divider. Inspect
for cracks, bulging, discoloring etc.

try that
Zeno