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dead CTC203

We inherited an RCA F32668 TV (CTC203CA6 chassis), vintage Jan 2001. But as Dr. McCoy on Star Trek used to say, "It's dead, Jim."

On opening the unit, I found and replaced the blown chassis fuse. On plugging the set back in, saw bright white sparks from the vicinity of the fuse. Quickly (too late?) powered off, found that the leads had melted off the RT14201 thermistor. Tried to power the set back on w/o the thermistor (based on previous advice that as part of the degauss circuit, don't really need it), but the TV is still dead.

When the set is plugged in there is line voltage across the fuse, and about 2 volts across the open thermistor leads.

Thanks in advice for any advice anyone can offer.

Reply to
Big Al
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Lots of common problems with the CTC 203 chassis. The thermistor is what blew the fuse. Make sure the large cement power resistor isn't bad. Did the fuse go again? Check standby voltages, & does the T.V. "squeak" at plug in? It should. Repair the horizontal drive coil, & post your findings. Was the unit dead, or just no video first, before it went? Does it try to startup three times? If so likely flyback. Rono.

Reply to
Rono

You need to troubleshoot the switch mode power supply first to verify that standby voltages are all good. Then troubleshoot the system control through the horizontal startup and power supply run voltages.

Just some standard tv troubleshooting for starters.

Reply to
dkuhajda

Not this one, If the fuse is popped, and one answer: caused by chain reaction all the way back to this hotglue on the L14401. When glue broke the solder on L14401 coil, corrupting the horizontal signal to base of the horizontal transistor (T14401), now blown, the power supply tries to drive short circuit through this to ground. Wheeeeeeeee! POP! 3 transistors & one resistor fries, finally fuse went up in a flash.

Not too bad to do, just get correct parts and remove that STUPID (aka money-maker) glue off the L14401 coil (remove coil and clean all glue off, dig out glue of that tiny hole for L14401's lead, reinstall new parts and coil, solder. Done.

Cheers, Wizard

Reply to
Jason D.

Also glue around the two crystals near the LA7612 IC and the very common flyback failure causing a shorted output.

Reply to
RonKZ650

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