Re: Sony KV32S22 - half-way back from the dead - what now?


"b" <reverend_rogers@xxxxxxxxx> wrote in message
news:1140444507.910310.193630@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

J. Michael Milner wrote:
My 1997 vintage KV32S22 died completely during the final moments of the
AFC
playoff game last month. After reading this group and a bunch of
googles, I
decided to give repair a chance. A few minutes with a meter showed the
common failure mode of a shorted HOT (Q502) that killed the PS choppers
(Q601 &Q602) and the fusible resistor (R607). I replaced the failed
transistors with quality OEMs and R607 with a Sony OEM. I removed,
cleaned,
and resoldered the HDT. The set now powers up, responds to the remote
(on/off, channel up/down, volume, mute, etc.), and provides sound but no
picture. The standby blinks at a constant rate which I understand means
a
bus problem or IK issue. Since the remote functions, I'm assuming the
issue
is IK.

I don't have an Oscope but I'd like to continue down a repair path. If
the
IK issue is due to a bad tube (common on the 32" sets like mine) I guess
it
means a new TV. Any easy way to test this? If not, what do I check
next?
Any "most likely" part replacement for this condition?

Mike

if the picture was ok before the set died, then why do you think the
tube is suddenly to blame? I dont think that is likely. This could be
a missing voltage ( open resistor?) somewhere in or near the power
supply. did you move the crt neckboard? are all cables in the right
position after reassembly?
-B..


I didn't see the picture tube as the set died (turned away during a
commercial or time-out) but the picture was OK up to then. The tube being
the initial source of the failure is just a guess based on what I've
summarized from google searches - 32" tubes seem to be a weak link for this
vintage of Sony TVs. Since the tube isn't a quick or cheap fix, I'd like to
rule it in or out before investing more in the repair process.

I did remove the crt neckboard as well as the anode cap to free the A board
from the chassis so I could get it to my workbench to do the parts
replacement. I've double-checked all the wire harness connections but I'll
triple-check again.

I see where the G board can be tested in isolation on this model so I'll
first check all the resistors and then see what the voltages are (one hand
in pocket).

Any other suggestions?

Mike


.

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