Hi, I have read a bunch of posts about the capacitors on circa 1990s
Mits but this set is different from most of the posts I've read. This
one has the 930B436 PIP (no bypass?) which does NOT have the surface
mount caps and I've replaced just about all of the electrolytics in the
set, I think I only have a few BP I can still replace. I have been
battling the inverted video (no luma high chroma) on my set now for
about 6 months and it seems to get better for 30 days at a time. Since
the failures started I have also had another symptom which is a fairly
loud audible buzz not from the speakers, but from the neck of the
picture tube. I have found that if you swith the channel back and forth
several times you can get something to sync and the buzz goes away.
Reseting the power also seems to work sometimes. On my last round of
capacitors (about 30) I again have a great picture but I still get
that buzz intermittently. I have a few areas where the traces were
compromised by the acid and I've had to make repairs but everything
seems sound. I read on a couple of posts about the neck of the picture
tube actually cracking which concerns me. This set came to me used with
a vertical problem (fixed with 5 capacitors) and I only have about $50
in caps in it plus the picture is great when it works, so I definately
want to get it fixed. For anyone reading this take the time and check
ALL of the capacitors as in every section there have been many "fishy"
caps if not just plain gunk leakin'! The condition of some of these
caps was so bad, it's surprising that the crazy thing could run at all.
If anyone has any tips to get rid of this buzz for good I sure would
appreciate it. Thanks!