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  #1  
Old 01-31-2008, 06:44 AM
johnfull johnfull is offline
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Final ColorTrak2000 model...

I've had a 31" ColorTrak 2000 since it was new
in 1990. It had a failure in the potentiometer
for the green drive while still under warranty and
was repaired for free. The set was sold as a 'monitor',
so there is absolutely no compensation for signal
strength variability from different sources.
LaserDiscs always looked washed out compared to
over the air or cable signals, but then DVDs came
along and gave the set a whole new gamut of color
and dynamic range.
The set was built in Canada. It was already under
Thompson labeling, but I think was leftover from
previous ownership. It was the last year before
RCA came out with 'ProScan' as their flagship.
The set has excellent color-rendering capability
and will be great to run with the new HDTV signals,
when converter boxes become available.
It does have a problem that has baffled techies
over the years. In humid weather, it will shut down
and go into oscillation of startup and shutdown
without becoming useable again. Sounds like a
major defect, but I found the source of the problem after years of study on the interned and
my own non-technical observations. There is a
tall, rectangular white ceramic resistor in the
high voltage section which can be pushe with a
wooden dowel to re-set the TV to normal. It works
every time, though sometimes bearing repeating
2 or rarely 3 or 4 times to get weeks and weeks
of use once again. I keep the back cover loosely
attached so that I can open and poke when needed.
It's something about the circuit board, I know,and
it's something that would condemn most of these
sets to the ash heap of history. But the picture is
so clear and focused and wide-spectrum in color.
What a shame, eh?
Does anyone know the specs on the final ColorTrak2000?
I think it was the last year before Invar masks,
so it's not overly bright. It has lots of useless
digitial effects built into it and the large remote
control. A real curiosity!
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  #2  
Old 01-31-2008, 09:31 AM
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brokenbroken brokenbroken is offline
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The first thing I would try is to re-solder that resistor to the board and check connections on and re-solder the other connections in that area.
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  #3  
Old 01-31-2008, 11:03 AM
MRX37 MRX37 is offline
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I don't think yours is the final Colortrak 2000 model. I had a Colortrak 2000 from 1991.
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  #4  
Old 01-31-2008, 12:05 PM
colortrakker colortrakker is offline
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And I have a ColorTrak from 1992. Great set.
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  #5  
Old 02-01-2008, 03:43 PM
johnfull johnfull is offline
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Quote:
Originally Posted by MRX37 View Post
I don't think yours is the final Colortrak 2000 model. I had a Colortrak 2000 from 1991.

I won't argue that.
The store was giving these away at half price the
year I got it and then they came out with ProScan.
It's great with a good signal, but absolute crap
with VCR tape or weak over the air. Even
LaserDisc through a top of the line Pioneer seemed
weak.
But DVDs are sharp and bright with great contrast
and no color bleed.
It seems that RCA had mastered the color gamut
pretty well (still weak in turquoise) but didn't
delve into the world of compensation for various
defects in signals. On the other hand, I bought a
little JVC 19" the same year and every source
shown on it was saturated and razor sharp and
high contrast. I bought a 32" JVC flat tube a
couple of years ago, and they've continued that
tradition into the present day. There is a lot of
voodoo science in making all sources look acceptable
on a phosphor screen. RCA gave up too early...
But I love the old ColorTrak2000 for DVDs and
will look forward to a new life for it with the HDTV
converters, when available.
Anybody have any thoughts on verrtical compression
on older sets? I'm thinking of installing a switch
to have a second potentiometer in the vertical size
circuit. The 32" JVC has this feature and it makes
a picture as sharp as PAL or even French SECAM.
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  #6  
Old 02-02-2008, 06:29 AM
johnfull johnfull is offline
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Quote:
Originally Posted by colortrakker View Post
And I have a ColorTrak from 1992. Great set.
The '2000' went away.
The ColorTrak line stuck around, but RCA gave
up the flagship under its own name and signed it
ProScan instead. At least, that's how I saw the
marketing. I think ColorTrak is STILL around in
the RCA line, but the early 90s ended the 2000,
which had begun back in the mid 60s...
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  #7  
Old 02-02-2008, 06:36 AM
johnfull johnfull is offline
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Quote:
Originally Posted by brokenbroken View Post
The first thing I would try is to re-solder that resistor to the board and check connections on and re-solder the other connections in that area.
Thanks.
I don't think it's that actual ceramic resistor that
is the culprit, though. From what I've read over the
years, there is some mysterious crack in the circuit
board that causes the problem. It's also got the
other problem of a poorly-shielded tuner that so
many have mentioned. The lefthand side of the
picture is washed out in solid black scenes on some
channels more than on others. That is supposed
to be a soldering issue, too, but I ignore it, since
I only watch over-the-air occasionally and can use
the tuner of the VCR anyway. HDTV converters
will make it obsolete next year, also.
I have NOT had the digital memory problems that
others have mentioned -- the EEPROM, I think it's
called. The only digital anomaly I get is when the
set has to be poked with a stick, the picture comes
on all weird and the 'Off' button for digital special
effects clears that up. In other words, the re-set
puts the set into digital effects mode. I still don't
quite understand why they spent money on that
stuff at the expense of some better signal processing. The color decoding circuits are top notch, though. Great color fidelity.
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  #8  
Old 12-28-2008, 09:51 PM
johnfull johnfull is offline
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My degausser died on the venerable ColorTrak2000 31" monitor.
It made a crackling sound and the picture came on with a bright
magenta frame around a bright green oval in the middle of the
screen. I was afraid the picture tube had gone bad, but I managed
to get normal color back in the center of the tube. The degausser
still works, but without the surge at the beginning, so it is worse
than useless. I've got a bulk demagnetizer around somewhere
to try on it. The screen is too big for little electric motors around
the house to do much good. I see degaussers on ebay. I hate
to lose this nice set, since it works beautifully with the DTV
converter box. Really nice, subtle colors, especially flesh tones.
You don't get that kind of subtlety in the new sets...
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  #9  
Old 12-28-2008, 10:16 PM
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radiotvnut radiotvnut is offline
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Your degaussing issue:
It's probably due to a defective thermistor in the degaussing circuit. RCA thermistors from the '90's are bad about falling apart. I've seen many where the leads would break loose from the body and barely be making contact. I've never seen a degaussing coil in one of these fail. In fact, I've only seen two degaussing coils fail in all of the TV's that I've messed with over the past 19 years.

Your shutdown problem:
I agree that bad solder connections are causing it. Try resoldering the horizontal drive transformer, the flyback, the horizontal output transistor, and the connections around that big resistor. I don't know why; but, several companies experienced trouble with the horizontal drive xfmr being soldered poorly. What chassis (CTCxxx) does your set use?

The latest colortrak 2000 model that I've seen was from around '92. Then, the Proscan line came along. Boy, I remember the local dealers playing up on how advanced the Proscan line was. I had a '91 27" that uses something like a CTC157 or 159 chassis. It was a TV shop reject and played well after I changed the flyback and HOT. I used it for several years and then sold it when I needed $.
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  #10  
Old 12-29-2008, 07:55 AM
johnfull johnfull is offline
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It's chassis CTC140.
Model F313255B.
The thing that happened with the degausser -- I'm
ashamed to admit -- I have a long wooden dowel that
I use to push on the white ceramic obelisk resistor to
re-set the TV when it goes into its switching on and off
hysteresis. I was a bit careless the other day, when the
set did this for the first time in many months and the
dowel slipped off and hit something on the circuit board
behind the resistor -- further toward th middle and under
the picture tube somewhat. I think it was the thermistor
because an orange glow briefly appeared from the spot I
hit and then the set was on normally. I often have to
repeat the punching procedure and this was one of those
times. The next time I clicked the TV on, I saw a white
spark come from a region slightly more outboard from the
place I hit -- more in the high voltage area. The TV came
on normally and worked all day. The next morning, I turned on the set and a zapping/crackling sound came
from the TV and the picture came on with the magnetized
magenta frame around a green oval that I described.
After that, the degausser never made the deep thump
when it switched on, so I'm thinking that a capacitor or
other high-voltage assist died in the flash of light that I
saw the previous day. So I've unplugged the degausser
because it makes a mess of the picture after I've done the
best I can to hand-demagnetize the screen. I found an old
bulk eraser for tapes tucked away and it does pretty well.
Its problem is that it isn't a big enough field for such a
large tube, so the bottom corners stay pink when the rest
is clear. I think they might age back to normal with time
and besides most programming on the DTV is 16x9,
where the bottom of the tube is idle anyway.
I am not confident enough of my ability to solder such
tiny parts to take the set apart, so I might just leave it
alone. I still love the old set for its color fidelity...
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  #11  
Old 01-02-2009, 12:18 AM
Geoff Bourquin Geoff Bourquin is offline
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CTC140 with random shutdown????

Check the connections on the diode SIP board in the main power supply. This is a little (about 2 inches) board standing on edge in the power supply. I've fixed hundreds of those sets by resoldering the connections on that little board. You'll need to take it off of the main board to do it right. I think it has 7 wires that connect it to the main board.
I've also seen a lot of them with a bad diode.....the big diode on that little board. I think it is part number 164589--someone check me on that as I am nowhere near a service manual right now. It'll test good with a meter, but try to suck an amp through it and it'll fail.

As said before, the thermistors on these sets seem to just fall to pieces. get a new one, p/n 207768 and you'll be good to go

There are other places that could have bad connections too, so get a strong light and take a close look.

Good luck!
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  #12  
Old 01-02-2009, 05:13 AM
johnfull johnfull is offline
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The random shutdown of the set is a different issue from
the degausser failure. The degausser had been working fine
until my wooden dowel slipped off the large obelisk resistor
and hit the circuit board behind. That caused a yellow light,
like something glowing red hot briefly. This crippled the
degausser, but did not kill it. It still puts out a little bit of
current and shuts off gradually, as if the thermistor is still
working. There just isn't enough juice in that circuit to
properly demagnetize and instead caused a magnetization
that ruins the picture. So I unplugged the degausser at the
little connector on the wires coming off the circuit board.
End of that story, unless someone knows how current is
supplied to the degausser circuit and how it can be
restored to full value. Otherwise, hand-degaussing is
adequate.
I haven't had any further intermittent shutdowns of the
set as yet. For a couple of days after the accident with
the wooden dowel, the vertical size would vibrate slightly,
but this effect went away. The telltale horizontal size
shrinkage that precedes the intermittent shutdown wasn't
happening, though. It was something new.
So now I have a beautiful picture except for a magenta
lefthand bottom corner and a spot slightly inboard from
the righthand corner. These persist even after hand-
degaussing with a bulk eraser. I'm searching ebay and
other sites for a large-diameter degaussing coil. I notice
that ebay has many of the really cheap green rectangular
model degaussers for sale cheap. I wonder why...
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  #13  
Old 01-02-2009, 11:07 PM
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bgadow bgadow is offline
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I had an RCA console given to me that was about that same age, I can't recall the chassis number. It had 2 problems: 1)the degaussing thermistor. I first replaced it with one from my junkbox which caused the fuse to blow. Next I swapped one in from a junker Zenith 19" and it worked fine. 2) Sometimes it would not power-up. Keep hitting the button (or remote) and eventually it would fire up. Someone suggested replacing a few caps and it worked. One in particular was obviously leaking.
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  #14  
Old 01-04-2009, 11:31 AM
johnfull johnfull is offline
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Does anyone know if these old ColorTrak2000 models qualify as
'studio' monitors? I mean, with the colors filtered to meet NTSC
standards. I know that the set doesn't compensate for different
signal strengths like so many always have. What you input is
what you get back out. In the early days, LaserDisc were a huge
disappointment because of the relatively shallow luminance and
chrominance gamuts. The set wouldn't make them pop with
compensation. But DVDs play superbly, with deep blacks and
saturated colors and subtlety of tone in between. Same with
the new little DigitalStream DTV converter. Reds and yellows
and even deep greens are in proper register. Turquoise is about
the only color that won't play too well. Green phosphor is too
yellow for that. But the brightness of the set is compromised by
keeping the colors true, I think. In a dark room, it's superb,
but by daylight, it is a bit dim. Always has been. Compared to
the 'brighter is better' decade that preceded it, some might have
felt it was a step backwards.
I have a JVC of similar screen size -- the 'flat' tube 32 inch model
and it has a very bright picture, but a coarser aperature grille and
is prone to poor color reproduction on analog signals. It also is
not as subtle with the DTV signal. It's perfect with DVDs, though.
I still prefer the ColorTrack2000 of 1989 to the JVC or 2004.
Don't even get me started on a widescreen Sony HDTV tube set
that graced my home for a year or so. Horrible color fidelity!
I would think that HDTV would finally allow receivers and
broadcasters to standardize -- like PhotoShop did for computers.
But I have seen no evidence of that so far...
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  #15  
Old 01-12-2009, 05:59 AM
johnfull johnfull is offline
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I helped a friend install a new Toshiba Regza 42" LCD HDTV.
It has bright saturated colors, but faces are yellow.
I still prefer my old ColorTrak2000 for color fidelity...
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