RCA FKR468WR repair/restoration

[lti]

This is my mother's old TV that hasn't been used in years. When I plugged it in today, I noticed these problems:

• Incorrect colors
• Severe pincushion
• Streaking colors
• Objects shrink vertically as they approach the bottom of the screen
• Images are either too tall or too short
• Bright lines on the sides of objects
• Dirty brightness (black level) control

Are there any problems other than bad caps and the dirty brightness control? This TV sat in the basement for at least 10 years.

[Wizard]

Re: RCA FKR468WR repair/restoration

These usually don't have bad caps, just bad joints on all heavy components like large resistors, flyback etc. Cannot resolder, have to take each component out and scrape the tinned part clean with razor and resolder back in. Be care with the PCB it is not forgiviing to too much heat.

Cheers, Wizard

[lti]

Re: RCA FKR468WR repair/restoration

What would require the component leads to be cleaned in that way?

This TV worked before it was moved to the basement. That was 10-15 years ago. It wasn't used or even plugged in until yesterday.

[Th3_uN1Qu3]

Re: RCA FKR468WR repair/restoration

What would require the component leads to be cleaned in that way?

Humidity caused corrosion. You'll definitely get a lot of that from 10+ years in a basement.

[lti]

Re: RCA FKR468WR repair/restoration

I took the back cover off and found some bad solder joints on the neck board. I just need to bring it upstairs where there is enough light for me to work on it. I'm not looking forward to bringing something that big and oddly shaped up the stairs. At least it isn't heavy.

[lti]

Re: RCA FKR468WR repair/restoration

I just found that R417 on the main board has become so hot that the solder and the resistor's leads turned black and the board started to crumble and fall apart. It appears to have the code violet, black, red, brown, gold. I was able to remove the old solder, but I can't get fresh solder to stick. I will post pictures later. If anybody has seen the CTC118A chassis and knows the correct value of this resistor, I would like to know what value it should be.

This TV has been repaired before. I was told that it lost both the picture and sound at that time.

[lti]

Re: RCA FKR468WR repair/restoration

I just finished resoldering. The vertical height problem is slightly better, but nothing else changed. By scraping the leads of the resistor, I was able to get solder to stick to it. I also cleaned the brightness control.

[lti]

Re: RCA FKR468WR repair/restoration

Here is the resistor.

I also found another problem: The image is too wide, and I can't figure out how to adjust the horizontal width.

I also haven't been able to get a good image. White, orange, and light green appear yellow, gray appears blue, and red objects appear brown.

[cadillacman]

Re: RCA FKR468WR repair/restoration

man i dont know.. i run into 80s arcade monitors( very simular to tube tvs of the era) and i see alot of issues with bad caps due to age/heat. It may be worth your time to recap this thing, although i do understand thats a krapton of work.

if anything like an arcade game monitor, there should be a horizontal width coil somewhere, not a pot.

theres basically a allen(hex) shaped slug of ferrite with threads on it. This is housed insde a coil. moving the ferrite will increase or dectrase horizontal width.


when you find it, DO NOT use a metal allen wrench to asjust it. You will likely break it and it will also get RED HOT in a matter or seconds due to induction.. youll want a set of plastic tools, let me search and see if i can show ya what im talking about.


EDIT
here ya go. Like i said i do not know if this applies to your set but either way its interesting to learn about.
http://www.arcaderepairtips.com/2010...al-width-coil/


incorrect colors, i would suspect perhaps the tube has become lightly magnatized over the course of bieng moved around. Most sets have an internal degauss function that will dissipate this after a few power cycles( several mins on several mins off) but if that doesent do it you may need to manually degauss with a degaussing ring.

http://cgi.ebay.com/MONITOR-DEGAUSSI...item53e7ccb76f

you want a ring, preferrably a big black one. A smaller red one MIGHT get you by. Avoid the wand type, they dont work worth a poo.

If there is a vertical linearity pot you may be able to adjust that squishing issue at the bottom out. If not, well then you definately have something to chase down. You may be able to adjust the color gains and biases there in the back to dial in the colors a little better.

[lti]

Re: RCA FKR468WR repair/restoration

I didn't see anything marked as a horizontal width adjustment.

I managed to get a decent picture by adjusting the bias and drive controls. It still doesn't look very good (a crappy Vizio LCD TV looks better), but it is slightly better. Resoldering the larger components may have fixed the bleeding/streaking problem and the brightness control now works properly, but the other problems I mentioned in previous posts still exist.

I also can't get an old RCA RCU300T universal remote to work with this TV. The IR receiver works (my wireless game controller really screwed with the TV - randomly changing channels and volume) and the remote worked with the Vizio TV (the remote was discontinued long before Vizio even existed).

Edit: I got the remote working.

[Th3_uN1Qu3]

Re: RCA FKR468WR repair/restoration

if anything like an arcade game monitor, there should be a horizontal width coil somewhere, not a pot.

theres basically a allen(hex) shaped slug of ferrite with threads on it. This is housed insde a coil. moving the ferrite will increase or dectrase horizontal width.


when you find it, DO NOT use a metal allen wrench to asjust it. You will likely break it and it will also get RED HOT in a matter or seconds due to induction..

100% accurate. Using a metal tool will also change the size of the picture when the tool is inside the coil vs when you take it out, so it's a real bad idea from all points of view.

Though, with a set that old, you're likely to find trimpots for everything, h-width included (a width coil is a cheap solution, older sets didn't cut costs that bad). Some have the trimpots at the front of the board (where the IR receiver and buttons sit) so you'll have to take the whole board out of the set and take a look.

[lti]

Re: RCA FKR468WR repair/restoration

There are some unmarked trimpots and adjustable coils, but they are spread out around the main board. The front panel has brightness, contrast, color, and tint controls.

Also, there is a coil labeled "Saw Out." What does it do?

[lti]

Re: RCA FKR468WR repair/restoration

Here is the label on the inside of the back cover. I see a 2-pin connector labeled "Horizontal Width" and a "pincushion transformer."

Currently, all of the original problems still exist, but the streaking/bleeding only happens with solid red objects on a black background.

With this TV, I can pick up two OTA channels (one Spanish channel and one religious channel) and the audio of a third (video is just static).