If the blue component of the picture is bow-tie shaped, you probably
have a fried convergence amplifier (CRT type sets only). They are
inside two modules in the typical CRT type RPTV. Each one has three
amplifiers inside, so you have two for each color. If the blue CRT
shares an amplifier from each module, you will need to replace both. I
recommend replacing both anyway because they are notorious for having a
high failure rate and you won't have to guess which one has the blue
amplifiers. Check the resistors connected to the middle pins of the
amplifiers - sometimes they get burned out when the amplifier fails.
The part number on the convergence module is STK392-nnn, where nnn is a
three digit number indicating the variant specifically used in your
set. Some of the variants are rated for a higher current than others,
and some have different pin arrangements. Make sure you get a
name-brand such as Sanyo or Samsung; there are some unbranded Chinese
copies out there with poor reliability. The typical price is $12-$25.
The modules are black plastic slabs about 3" wide by 1 3/4" high, with
the bottom corners trimmed off at a 45 degree angle. A row of pins
comes out of the bottom edge and go into the circuit board. They are
mounted on some sort of metal plate or radiator to dissipate heat (heat
sink). When you replace them, apply a very thin even coating of thermal
transfer grease to the metal plate on the backside of the module, and
clean off the old grease on the heat sink. You want only enough grease
to ensure a "wet contact" between the parts; more than that will
actually reduce heat transfer. While replacement is straightforward, it
does require skill at reworking soldered connections on circuit boards.
The hardest part will be restoring convergence since you tried to
adjust it. Be patient, and try to get the convergence points square to
each other so the picture isn't distorted. Adjust each one a little bit
at a time. There is some interaction between the adjustments, so what
you do on one part of the picture affects other areas.
Blue should converge on top of "yellow".Bad connection(s)
on blue convergence IC.Replace both IC's for durable repair.
Check pico fuses.Reset convergence alignment.
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