Color Classic Purple Trinitron

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Joined: Nov 14 2015
Posts: 6

This Color Classic glitches purple after being left on for about 5 minutes. When she starts up, the display is completely purple, but goes to white. She will eventually glitch, not to solid purple, but vertical purple strips at random purple hues. The CRT also has tons of static when it starts up. When she shuts down, you hear a noise similar sand falling, but it is the static discharge of the CRT. Is their a way to fix this? It's not the Color Classic it's probably the Trinitron. Is their anyway I can fix the Trinitron as I would like to keep it original. If not where can I get a replacement CRT?

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Joined: Oct 9 2013
Posts: 367
Re: Color Classic Purple Trinitron

First I'd make sure the video board is securely on the neck of the CRT.
Second is you can try adjusting the internal video controls. Sometimes messing with the RGB, Green Background, even the geometry controls can knock a finnicky CRT back into shape (at least in my limited experience but specifically with the CCs I have had)

If you are unsure how to disassemble the CC or what I am talking about, download the CC Service Source Manual HERE.
Zan

eeun's picture
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Joined: Dec 19 2003
Posts: 1891
Re: Color Classic Purple Trinitron

What Zan said. But eliminate all the simple stuff first. Check all connections between the analog board and crt. Be careful moving any of the adjustment pots around. Your problem might be solved by wiggling the pots to make sure they have a good connection, but if you move them keep track of their position as best you can. It's a pain to have to go through re-adjusting them to get you monitor looking nice again (assuming that fixed it).

I'd guess your problem is related to heat changing something from being connected to...less connected since time powered up is a factor. Could be a break on the board, a bad part, a bad solder. It's less likely to be the actual tube and electronics on the yoke that are causing problems.

There are two large resistors on the analog board that were often recommended for replacement. They were around the center of the analog board, and usually easy to spot by how they heat-darkened the board around them. Can't remember the symptoms their failure caused, though.

Anyway, get inside and check the easy stuff first. And note any scorching, burning, darkening on the board and swelling or damage visible on components. And make sure the anode cap on the top of the monitor is well connected.

Basic CRT safety - link or equivalent should be required reading for working near a CRT:
http://www.peachpit.com/articles/article.aspx?p=759704&seqNum=2

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Joined: Nov 14 2015
Posts: 6
Re: Color Classic Purple Trinitron

Unfortunately, I have not been able to disassemble her yet. I can probably do that later today. I have messed with the RGB settings and she stayed purple the whole time. I'm confused, as the color classic will fix herself after awhile, and go back. The trinitron seems tdo go dark purple, complete white, then purple giltch. Does that mean that she is not getting enough power?

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Joined: Nov 14 2015
Posts: 6
Re: Color Classic Purple Trinitron

I'm scared guys. Please help.

Quote:

I took off the case of the Color Classic. It

was doing some weird purple glitch with the

screen. I tweaked the video board and turned

it on without the case. The screen was not

purple. I was excited but left it on just in

case it went back to purple. After awhile it

showed the loading watch, so I thought it

was going into screensaver. It still loaded,

but instead of the normal city, it flashed

"Cheshire Cat: Have you noticed that I'm not

all there?" It only stayed there for about two

seconds. After that message had disappeared,

the screen imminently glitches purple again.

Now I'm scared to work on it again

eeun's picture
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Joined: Dec 19 2003
Posts: 1891
Re: Color Classic Purple Trinitron

You don't need a technician, you need a priest.

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"Give a man a fire, he's warm for a day. Set a man on fire and he's warm for the rest of his life."
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Joined: Nov 14 2015
Posts: 6
Re: Color Classic Purple Trinitron

eeun wrote:

You don't need a technician, you need a priest.

XD
I later realized that I enabled After Dark somehow. But back on her Trinitron. Should I take off the video board, or just wiggle it again? And what do I do with the video board if I should take it off?

eeun's picture
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Joined: Dec 19 2003
Posts: 1891
Re: Color Classic Purple Trinitron

No guarantees it'll work for you, but I sometimes feel like a bit of a fraud for looking like an IT Guru to my family and friends when I've merely taken hardware apart and put it back together again to get it working.

There's no harm in taking it all apart, and that'll get you a closer look at all components and connectors. Maybe post some photos if you can if anything looks questionable. *

*also helpful reference for putting it all back together.

__________________

"Give a man a fire, he's warm for a day. Set a man on fire and he's warm for the rest of his life."
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Joined: Oct 9 2013
Posts: 367
Re: Color Classic Purple Trinitron

Take it off, inspect the pins, make sure it's lined up properly and reattach it. See what happens. On my CCs there was a small blob of "caulk" (glue, whatever) that attached the metal shield on the Video Board. I had to replace it on my last one, I used 4200. I'll look to see if I can find the photos to show you what I mean. If not, I'll take one apart when I have a sec.

If the video still drops back to Purple after reattching the video board I'd mess with the POTS for the video adjustments internally (see the link I gave you to the service manual)

I've seen it make the difference and other times it didn't do squat because there were more serious issues.
Zan