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-   -   Zenith Chromacolor ii set problems (http://www.videokarma.org/showthread.php?t=270349)

Sealtest 04-14-2018 10:16 PM

Zenith Chromacolor ii set problems
 
Hello all, I got a free Chromacolor II today that I need a bit of help with. The tv powers on but there is no picture at all. The tube lights up in the neck but displays nothing but darkness. I was told the tv worked fine in 2010 before being stored in a closet, so I was guessing a cap issue.

My thing is I just do not know where to start with tvs since I mostly do vintage audio. Any help is really appreciated.

Electronic M 04-15-2018 09:18 AM

Got the right voltage of HV? Got a schematic to check electron gun voltages against?

Sealtest 04-16-2018 04:09 PM

Actually I got this thing going. The screen was pitch black so I looked on the boards for something with a light or brightness label. I found a "low level luminescence" board and found a bad cap along with a few bad joints along some sort of long white component with many legs. All of this was done in my mobile shop (A Volvo 240) in maybe 30 minuites. So if anyone else has this issue don't worry too much.

Replaced the cap and re soldered the joints, and the tv is back alive (for now anyways). I guess I should have waited to make a thread, but sometimes it's nice to know where to look first.

Thanks!

zeno 04-16-2018 04:53 PM

Very nice work. The long white pkg is a resistor pack. They were made in Littleton, Ma. just 2 miles from my shop ! Anyhows whenever one
came in that was a "must check" problem even if there was no brite
complaint. Whenever you see them on any Zenith board check the
connections. They get hot & get cold joints.

73 Zeno
LFOD !

Laserdisc 04-22-2018 11:00 AM

This set is actually mine now, I thought about starting a new thread to avoid confusion but there's no sense in having multiple threads on the same set. Sealtest is welcome to take over my thread on the TV I traded him.

Now,on to why I'm here. This set has one minor issue that I'd like to fix. It's constantly got snow like it's an over the air signal even when I feed it a signal. I have heard that CCII sets have a fantastic picture but so far my 16" system 3 impresses me more than this 23" CCII.

Laserdisc 04-22-2018 12:28 PM

And the horizontal just died after watching a few hours of tv.

Laserdisc 04-22-2018 12:33 PM

1 Attachment(s)
Here's what it does

zeno 04-22-2018 05:45 PM

Depending on the exact chassis check the 330 ohm resistor
on the bottom left of the 9-90 horz board. Replace with a
1 watt flameproof.

For snow try the RF AGC on 9-87 board. With a STRONG signal
adjust til the snow JUST clears up & you have no jitter.

As far as the S3 looking better it has an EFL CRT & will be brighter
& sharper. It may also have a comb filter which makes a huge
difference in resolution.

73 Zeno:smoke:
LFOD !

TUD1 04-22-2018 06:32 PM

Quote:

Originally Posted by Laserdisc (Post 3198530)
This set is actually mine now, I thought about starting a new thread to avoid confusion but there's no sense in having multiple threads on the same set. Sealtest is welcome to take over my thread on the TV I traded him.

Now,on to why I'm here. This set has one minor issue that I'd like to fix. It's constantly got snow like it's an over the air signal even when I feed it a signal. I have heard that CCII sets have a fantastic picture but so far my 16" system 3 impresses me more than this 23" CCII.

I know exactly what you mean about the snow. I just got a 17" remote Chromacolor II set with an extremely bad snow problem that I'd like to clean up and get going. Snow in the picture is one thing that I will NOT tolerate on an old set. I want it Krystal clear.

Laserdisc 05-17-2018 01:02 PM

Board is a 9-90-02c "horizontal apc and osc" I'm not seeing any toasty resistors and I don't see a 330ohm one.

zeno 05-17-2018 04:02 PM

Quote:

Originally Posted by Laserdisc (Post 3199665)
Board is a 9-90-02c "horizontal apc and osc" I'm not seeing any toasty resistors and I don't see a 330ohm one.

The -02 is a redesign. IIRC had an IC & a horz hold pot. There still may
be a horz osc coil mounted along the bottom of the chassis. It may
be against its stop. If so pull out on the outer sleeve & turn it beyond
the stop.
The other slim chance is the 9-87 board. It has the sync sep & AGC
coming from it & may cause the snow also. BUT no horz sync causes a slow
sideways roll not diagonal lines as a rule.

73 Zeno:smoke:
LFOD !

Laserdisc 05-17-2018 04:59 PM

That's the thing. It played fine for around 2 hours watching TV and then the horizontal hold went off instantly with a small pop. This thing makes some interesting noises on power up I might record for you.

Laserdisc 05-17-2018 05:26 PM

https://youtu.be/6APtYKvBQrs

bgadow 05-17-2018 09:36 PM

I know it's simple but I'll ask anyway: all the connections coming in to the tuner are in good shape? Once, maybe twice now, I've had a bad 75-300 converter cause this, too.

zeno 05-18-2018 08:24 AM

Noise at turn on just the degausser. I would look in the 9-87 area.
It just dont look like the horz is off. Looks more AGC or video prob.
One long shot. These usually have the selector, two tuners & a
tuning control board. Tilt the chassis down & resolder the control
board under the connectors. If it has one big tuner resolder the tuner
under the connectors also.
BTW whats the chassis number? 23?C45 ?

73 Zeno:smoke:
LFOD !


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