Horizontal problems on a Trinitron KV1712

[zenith2134]

Hey everyone! Hope everyone is enjoying their afternoon.

Well, I posted a thread a few months ago about this Sony set which I found curbside. Originally, all was great, then the horiz started losing sync and shrinking/breathing.

I replaced about 5 caps, around the horizontal output and HV transformer, which were testing weak. I check the majority of all the other caps, and these were within spec. I patched up the set, and all was great again.

The raster now fluctuates in size and at times the whole raster rapidly changes size from medium to regular, as if the HV is out of control. However, the high voltage is stable and fine. Does anyone know if this was a common fault with these sets? The TV has a truly amazing picture when it works.

Also, this was built in 1977, and the CRT is very strong still. Please, experts, I need some help here. Thanks