This Samsumg set is clearly not going to be an easy fix. It came in with
severe convergence problems - no two colors converged properly at any point
on the screen. I started by checking the two large convergence IC's
(STK392-010); both had the correct supply voltages, but two of the three
sections on one IC were not functioning at all (input present but no output)
so I assumed the IC was bad. For good measure, I replaced both IC's. Once
powered up, the picture was still severely distorted but this time, ICZ103
(which was formerly bad) now overheats severely. So I tried disconnecting
the output leads from that IC, and it now runs cold - but of course the
picture is still distorted.
At this point I suspect an underlying fault somewhere else, putting an
excessive load on the IC and causing it to fail. I checked the three yokes
and all measure the exact same impedance, ruling out the possibility of a
shorted yoke. Because of the complexity of this set, it would be pointless
to venture any deeper without the aid of a service manual, or at least some
advice as to what the problem might be.
Thanks for any advice.