Weee! another Trash TV saved!
 

I did not really want it, as it was solid state, but when my friends offered it, I was not gonna refuse.
http://suzaku.live-evil.org/79377184...81A401108.jpeg

It's a RCA CTC-177

And its DEAD Jim!

No power no nothing!

found a DEAD short on the HOT, but to my surprise, the transistor was NOT blown, but the 140V line to it was shorted DEAD.

http://suzaku.live-evil.org/blownaaa.jpg
Fried diode.
and open cap.
The regulator might be fried too, not sure.
Oh and the thermistor is GONE, waiting for a new one.

I was right! the regulator is TOAST! replaced the shorted diode, not sure why it let go, new caps C4107/C4105 and still DEAD set. 180V on pin 1 of T4101.
so much for this IC being self protecting.

It's alive!

http://suzaku.live-evil.org/20260307_191504.jpg

Replaced the regulator, and it powered up.

Still not 100% yet, when it first came on, there was no vert sweep, then it slowly filled the screen.

More bad caps.

As mentioned, it does work. eventually!

http://suzaku.live-evil.org/0308260040.mp4

SAMS was very poor with the parts list on this set, many of the caps are not shown on the list, so I'm having to guess at the voltage rating, or just pick something way over. :(

http://suzaku.live-evil.org/caps.jpg

I can't really see what's in there, and want to get them BEFORE i pull them out...

I usually just pull the whole board, take out each cap one by one and make a spreadsheet of the cap number, voltage, value and temp. In any case, the Sam's (or the schematic) can be wrong, or there could be revisions. You always want to replace with what was originally in the set, not what's on the Sams if there is a disagreement. So it's best practice to pull it and go one by one.

Your video definitely shows bad caps around the vertical IC. You have that telltale vertical linearity issue where the scan lines unravel towards the top of the raster

Just about to place order for caps from Mouser, guessing the voltage value from what was seen on the schematic, most seemed to be 63v, ordered 100v, hopefully what was shown on the schematic are the correct values UF wise, if not, I can just re-order and have them in a day.

Also in the power supply, vertical has a dedicated feed line from the FBT, with 2 caps on it, 25v line I think, I have never seen a TV do what this does before, start with no V sweep at all, then expand to full screen after 40 seconds or so,

.

So what happened to Dr. Smith??

.

Major West reluctantly brought him back in so he could endanger the J2 another day!

Another annoying thing about this set is, it has AV inputs, both composite and svhs, but w/o a remote, you can't select it for input.

should be able to solve with either a universal remote, or an app.

a lot of older cell phones have an IR blaster, so if you can find a model for cheap (or just have one hanging around in a drawer) then you might be able to side-load a universal remote app on it and use that

i've got a samsung galaxy S6 with an IR blaster that I did this for many years ago, although I'm not completely sure how to locate the software anymore. when I did it, the S6 was still only a generation old or so

You mean S-video....SuperVHS (SVHS) is a videotape format with extended luminance resolution. S-video (S standing for Separate) is a video cable/connector standard where the luminance and chrominance components are sent via separate coax leads to avoid repeated luminance chrominance mixing and comb filtering.

Sorry to be pedantic, but it really bugs me when I see someone I consider smart mix them up.

It was very common to hear people refer to s-video as SVHS in the early days because that's the format that it was essentially created for in the marketplace. If you knew what s-video was in the 1980s, chances are it was because you had or knew aobut SVHS decks.

I think it just persisted and it doesn't bother me at all.

Replacing caps helped nothing at all. :tears: :thumbsdn: seems it may be a bad TDA8172, though I have never seen one act like this before, not work for the first few moments and then start to work after 40 sec.

https://www.youtube.com/watch?v=7neNVN-k4tQ :D

It's odd, cause when it works, it works well.
http://suzaku.live-evil.org/0310262115a.jpg

What SAMS says about vert debug.
http://suzaku.live-evil.org/vert-problem.jpg

Yes, the 25v is good.

And the output IC has a history of trouble. New one ordered.

Those era vert output ICs are generally touchy and often blow open when the caps attached to them drift too far out. They also run very hot and destroy the caps near them on the PCB, so they essentially kill themselves. Very common

It's oddly running cool for some reason, as in after sweep does start, and has been on for a while, shut down, grab the HS, and it's very cool.

I wish this stupid TV would make up it's mind...
NOW the last 5 time or so when i have turned it on or so, I have gotten full V sweep, but I am still going to change the output chip!

Did you say CTC177? Sorry for not getting back to you sooner. Are you familiar with the legacy of these sets? It is a microprocessor controlled set. May have been the first. The tuner shields get noisy and corrupt the EEPROM data. AND it might do anything after that!. MAY not even turn on. I usually start at the EEPROM. I install a socket and put in a known good EEPROM. You should first re-solder the tuner shield on the bottom of the circuit. A CTC177? Does it have PIP and stereo? Sweet. You should probably obtain the training manual. It was printed in 1993 so it's legacy technology by now! Might be able to download it from Electrotanya.

After fixing the fried power supply, it's been having no problems turning on, just getting full vertical sweep, first starting with a line, then expanding to a full perfect screen in 40 seconds, replacing caps did not seem to help it, and the day after I ordered a v-output chip, it seems to have stopped doing it... :tears:

Electrotanya has it! You should definitely download it. Tanya- what a doll! Also there are a number of TSB's for this set. After the CTC177 there should be some numbers and letters after it. RCA was the target of a class action lawsuit about this set. Very unreliable due to the tuner solder. The set is really on all the time. When you press the on button, all it does is starts the H&V scan and audio. I can see where a lightning strike nearby could scramble the data in the EEPROM. It was the new world order of TV sets at the time.

Agree 100% with Kf4rca on the tuner ground issues with these. As the miroprocessor-eprom controls everything with all service adjustments and tuner alignment via data to the LSI "tv-on-a -chip" these grounds will cause all sorts of intermittent issues. Unsolder the tuner shield on the bottom of the PCB and inspect / resolder all the tuner frame to board joints. These sets kept a lot of repair shops in business near the end of the line!

Now that you've passed CTC177 school, you are now qualified for CTC185 school.

I prefer my RCA-CTC90 as far as SS TVs go :P

This stupid set has gone back to the old habit of having no V sweep when first turned on and then expanding to a full perfect screen in 2-3 min, and then staying like that till shut off for a prolonged time.
I'm basically tired of messing with it as it was a free gift ( trash find), and I don't have a place inside for it yet (it's still in the garage).
So, what I'm planning to do is, hook up a filament interrupt relay (5v) on the neck PCB, off until turned on by switch on back of set, this will protect the screen from line burn before it fully has V sweep, turn on television, wait 2-3 min, hit switch to energize filaments of CRT.
This should work fine for the little that this set will be used. I have sill to find a place to put it, and a remote to use the advanced features.

channel 91 and 92 will get you the inputs on the tv