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-   -   I finally found another 1991 Colortrak 2000, with S video! (http://www.videokarma.org/showthread.php?t=190777)

MRX37 10-29-2008 08:11 PM

I finally found another 1991 Colortrak 2000, with S video!
 
It's a CTC 158B chassis. It was clogged with dust inside, so I cleaned that out. Someone also messed with the focus control. I readjusted that and it has that same Colortrak picture that I remember so fondly.

After I get it hooked up, I'll snap a pic of it. It looks a bit different from my old Colortrak 2000, but the screen and picture are the same. :D

zenithfan1 10-29-2008 08:51 PM

Can't wait to see it, those sets really did perform well. Glad you found it!

MRX37 10-29-2008 09:01 PM

http://i119.photobucket.com/albums/o...ortrak2000.jpg

The camera flash doesn't do the TV's picture justice.

No tinted picrture with the color down. No color bleeding with the color maxed out. Crosshatch pattern shows almost perfect convergence, and unlike my last Colortrak 2000, this one doesn't have a single nick or scratch in the screen!

radiotvnut 10-29-2008 10:03 PM

Nice find from the '90's. I've had many of these pass through here and they are generally good sets. Probably the last decent sets to bear the RCA name. Those Thomson CRT's usually hold up well; unlike Zenith tubes from the same time period. There is a transistor (Q901 luminance driver, IIRC) that I've seen fail. Also, I've seen bad vertical IC's, bad caps, power supply problems, an occasional flyback failure, etc. on these. Nothing that does not happen to any other set. I had the 27" version of this set that played perfect for years after a HOT and flyback replacement. In fact, it was playing fine when I got rid of it.

MRX37 10-29-2008 11:05 PM

I mentioned that I used to have one of these. the one I had was bought new in 1991, and it never gave me or my mom much trouble. I think it was repaired once because of a sound issue. The only reason I sold it was because the picture was tilted slightly (bonded yoke... yay), and the screen had a small nick in it.

I've seen 90's RCA's hold up pretty well. Found an RCA XL 100 from 1995 that had a like new picture. I managed to sell it not 5 hours after I listed it for sale.

zenith2134 10-30-2008 12:13 AM

That was a good set. I recall seeing those in car dealerships, hotels, restaurants and other public places around here where they were run hard. The Thompson CRTs did hold up very well. If anything, they were equal or better than the 80s RCA tubes.

Should last a long time! If it has any Sanyo caps used for the smaller values I'd change em out. Like the Toshiba sets from the same time, these sets seem plagued with these caps. Some batches were fine, though.

MRX37 10-30-2008 12:55 AM

Um, one picture flaw I've noticed. I've seen it alot on older TV's. Dark text on a light colored background smears on this TV. It makes a faint line all the way across the screen. Can anything be done about this? It's not color bleeding. The CRT is still bright and very sharp.

zenith2134 10-30-2008 01:07 AM

If it has a sharpness control, turn that down (closer to off) also, I've noticed a similar thing happen on sets with little or no DC restoration (which the ctc-158 certainly has) where the dark text gets washed out by the high contrast areas of the raster.

Just a hunch, but back off the contrast a bit and see if it helps. One of the video circuits may have low drive.

MRX37 10-30-2008 01:20 AM

Quote:

Originally Posted by zenith2134 (Post 2214493)
If it has a sharpness control, turn that down (closer to off) also, I've noticed a similar thing happen on sets with little or no DC restoration (which the ctc-158 certainly has) where the dark text gets washed out by the high contrast areas of the raster.

Just a hunch, but back off the contrast a bit and see if it helps. One of the video circuits may have low drive.

I'm already sure backing off the contrast will help. In fact, I wonder why it's set uip to 3/4 of the way by default? It was set at that on my original Colortrak too.

What would cause a video circuit to have low drive? Bad caps? I see this type of smearing on a lot of older TV's...

zenithfan1 10-30-2008 08:26 AM

I've seen the smearing too, I try not to pay attention but sometimes it looks bad. I notice it on my '75 GE 19CD chassis set and a few others, Zenith sets don't have much of an issue with it. Other than that, the picture is great. Great picture on the RCA by the way. Very nice find, these are usually all beat up and half dead by now. This one seems to have had a good life.

MRX37 10-30-2008 02:45 PM

Heh, it could have been cleaned more... the inside was nightmarishly filthy!

So, apart from playing with the contrast, what can be done about the smearing?

zenithfan1 10-30-2008 03:18 PM

I really don't think there is much that can be done. If so, it's out of my experience range. I would start at I.F and check through the video output section. Just a guess. Maybe there are some parts that could be brought into a closer tolerance.

radiotvnut 10-30-2008 03:38 PM

The most practical way would be with a 'scope and a signal generator and trace through the IF and video circuits to see if there is any "junk" on the signal. Frankly, the only way I'd go to that trouble would be if the problem was severe enough to bug me.

karmaman 10-30-2008 05:10 PM

The smearing is probably all the old caps in there, most of them lose capacitance over the years. A full recap might fix the smearing and would most definitely improve the picture. I notice it on a lot of old tv's too.

MRX37 10-30-2008 05:12 PM

Quote:

Originally Posted by karmaman (Post 2215848)
The smearing is probably all the old caps in there, most of them lose capacitance over the years. A full recap might fix the smearing and would most definitely improve the picture. I notice it on a lot of old tv's too.

This is what I'm thinking too, but I wanted confirmation before I start shotgunning caps.


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