Rescued 2001 RCA 36" F36669 with rainbow
 

Turns on and runs fine but I noticed discoloration at top right and bottom left of screen. Changes when I move it around the room. In another location, it was bottom right and bottom left. Any ideas?

It needs the CRT Degaussed.

It's supposed to do it automatically every time it's turned on cold, but their could be something wrong with the Degauss circuit, or the tube could be magnetized to an extent that the internal degauss coil can't fix it, if that's the case you will need to use an external degaussing coil like this one:

http://www.ebay.com/itm/GSG-Televisi...item5b0ff860df

Another possibility is the Shadow Mask inside the CRT is damaged, this can happen if the set was dropped or knocked over at some point, there's no fix for that except a new tube.

Degauss thermistors fell apart left & right on these.
IIRC its near where the AC cord comes in. Dime sized
& has leads soldered to it. You can usually resolder the leads.
Also IIRC these had orientation switches on the back marked
E-W etc. Dont remember how to set them though:scratch2:

BTW whats the chassis number CTC###

73 Zeno:smoke:

ctc203c. It moves around the screen when moved as gravity affects it.

http://www.videokarma.org/attachment...1&d=1428772475

Thought it was the older chassis. IIRC the 203 was the
last real RCA chassis. Look near where the DGS coil plugs
in for the thermistor.

73 Zeno:smoke:

The Earth's magnetic field could do that. Tap not real hard on the cabinet, and see if the false colors flap "in the breeze".

Do you hear a short buzz when you turn the set on when it's cold (ie, not been running for several hours). If not, the thermistor probably broke, and the set isn't doing a degauss upon power up.

Exactly! :yes:

While you are in the TV, check the solder on the Pincushion board - that was the number one gripe we had with the '203 - bad solder joints causing all sorts of problems. IIRC, it's on the right side of the chassis when looking at the back of the set.

Cheers,

And above ALL...the connections on the horizontal driver transformer path too !!

I would definitely try and degauss that tube. Those RCA tubes of that era are VERY reliable. a 207768 RCA part will replace the thermistor

I will open this up in the next couple of days and post what I find.:thmbsp:

Labeled C14207 on the board? near the ac line at back right corner. Don't see any loose connections or welds. I don't hear any sound that you normally get when first turned on. Just the first relay click and then the second. Otherwise very quiet.

Should be marked with an R number not C.
Not sure on the CTC203 but earlier chassis turned on/off
by turning on the hoz osc. The relay is for degauss & will
click twice. The relay contacts, thermistor & degauss coil
are all in series.

73 Zeno:smoke:

Been awhile since I saw a manual....but pertty sure you are right. Think the 203. ALSO has a constant running SMPS_-and it just switches the horiz on and off too, maybe along with a couple of lower lines. . In standby--it goes up some above the run level.....but more than full B+ is there on the H-out in standby. Relay only for degauss. If you are not hearing a pretty loud hum, for a second at turn on...the degauss ckt it NOT working. Coil might even be UNPLUGGED from board, near thermistor.

coil is plugged in. unplugged and plugged back in. No hum at all. just the two clicks. I did notice after having the back off and after cleaning that the colors are even worse now when turned on. Will get a pic of how it is now. Should I change out the thermistor? Its blue and located at the back edge near the power cord.

Can you get a hand degaussing coil....and go over the tube? If it is ok....you should be able to clear the problem up. just make SURE....it is at least 4 foot away from the set---when you plug in coil.. and then before you unplug the coil.

it MAY be so heavily magnetized.....that it takes some passes of the coil, over the front of the set and even behind it. just keep it AWAY from the neck of the tube.