This may be way out in left field, IE making a wild guess here, as I said, I have not worked on this type of TV before, could this possibly have something to do the HV power supply being off frequency (too high/low) and causing an odd resonance on the screen?
There only seems to be the .005 cap on the line, and if the osc is somehow de-tuned a bit, who knows what weird stuff it may do.

Hello,

I will look for the blip on pin 5 or 9 knowing there are some high voltages. I'm trying to figure a way how my scope will be able to read such voltages without causing any damages to the equipment. Please advise me. Cheers

Yamamaya42, don't go to New Jersey. They refer to everybody as "you guys."

I was born in Poughkeepsie, then I moved to hell at the age of 10. (aka, Texas ) :sigh:

I wouldn't want to advise you on using a scope considering the voltages present.

As an alternative, I would do this - take a cap of .1 uf or higher, and jump it from pin 5 to ground and see if it kills the blip. Then from pin 9 to ground and see. Try the cathode too for the heck of it (pin 2).

But as a precaution, first measure voltage on the pins to be sure it doesn't exceed the cap's voltage rating.

old_coot88,

Will do. !

Thanks

Cheers

Caution! I believe the CRT except for cathode and G1 are all floating on the high voltage (thousands? of volts).

If you have a spare replacement .005 cap for C54/C55, that could work to protect your scope, as it has the required voltage rating for whatever is on the CRT.

A similar Admiral schematic
https://www.earlytelevision.org/pdf/..._rider_tv3.pdf
lists C54/c55 as .005 mfd, 6000 volts.