On 6 Apr 2004 05:11:47 -0700, (Dieter
Kedrowitsch) wrote:

Hello! I was given a 2 year old RCA F27442 TV that died. When
plugged in, it would make a high piched squeeling noise. After a

Hi Dieter,

Good research through.

This is fairly simple to repair but the tricky part getting the leads
bent so that Q14101 is flat against the heatsink because the lead
holes is tiny. Leave the thermal pad on that heatsink, just carefully
remove the blown transistor after getting clip off.

Start by unsoldering & remove L14401 coil, remove all glue, clear one
coil's wire hole of glue, reinstall. Four transistors: one Q14401,
(horizontal transistor) and three transistors: Q14101, Q14102 and
Q14103) total, one flameproof 1/4W 43 ohm (R14107) resistor and a
fuse.

These are RCA part numbers: MCM should have them.

Q14101: 244223
Q14102: 147665
Q14103: 232218
R14107: 244214

Q14401: 242224 (horizontal transistor, big one)

F14201: Fast blow 5A in GMA size fuse.

This parts especially power supply parts are same for *all* CTC203 and
ATC113 chassis EXCEPT the horizontal transistor, depends on chassis
and tube size.

Next time don't let any dead TVs squealing, saves trouble of replacing
more parts.

Horizontal transistor part number 242224 is used in both 25" and 27",
in fact I stock that 10 at a time along with power supply parts. That
glue on that L14401 is common as dirt.

Don't sub the horizontal transistor please. Q14102 & Q14103 I think
were MPSA06 and MPS8599, they're jellybean transistors pennies each.
KSA06 is also used for MPSA06.

Get horizontal transitor middle leg (collector) prebent that all legs
are loose in their holes with transistor against the heatsink. Then
put thin layer heatsink grease on the backside of horizontal
transistor where it meets heatsink before clamping.

On CTC203 only:

If you have black plastic bracket that holds flyback transformer,
horizontal heatsink and gemstar module (square metal box). Remove
plastic bracket and toss it. Not worth leaving that bracket in, this
traps heat where horizontal heatsink is. That bracket was useful to
protect board from breaking during shipping from factory to the
distributors then to dealers/stores.

On ATC113 only: cannot leave out the black bracket but simple
modification to bracket, cut off just beyond the two twist tabs for
the horizontal transistor to let air circulate freely for the
horizontal heatsink cooling. That bracket holds the upright board,
hence the modification.

Cheers,

Wizard