G07 rainbow bloom after powerdown

akeym

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So I just recapped a G07 chassis and also replaced the flyback and width coil at the same time. I'm pretty certain everything has been hooked back up correctly.. but now when I power off my G07, I get this lovely rainbow of colors on my screen that takes a few minutes to disappear.

What is this phenomenon called, and what did I screw up while working on this chassis? Any specific areas I should be looking at?
 

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I've seen this happen with a certain colour, but I've never seen anything like that. I have absolutely no idea why it happens, but I don't think it's anything to worry about.
 
I've seen this on quite a few monitors over the years. I have no idea why it happens. I've never worried about it.

Edward
 
Weird. I don't remember this happening before I did the overhaul.. I'm going to pull the board and check for shorted traces where I did my work just in case.

Hewitson: I'd feel better if it was just one color because I figure there's something wrong with one of the gun driver/circuit.. but a spectrum? What would cause that..

The most info I've found so far about this effect is here: http://www.repairfaq.org/sam/crtfaq.htm#crtagl


Thanks for the responses.
 
Been forever since I've messed with this stuff, so forgive me for not having specifics....
It has something to do with the High Voltage not bleeding off enough after shutdown. If you were to discharge the monitor you would see it instantly go away if I recall. So I would investigate the new flyback and it associated circuits leading to ground. (including the Focus/Screen potentiometer block)
Or possibly a color gun/neckboard grounding issue.

It's a residual HV thing keeping the phosphors lit up is all I remember at the moment.
 
My Tron's monitor has always done that since I got it in 2008. Doesn't seem to ever cause any issues - the monitor is great otherwise. Although I've always been curious about it.
 
Been forever since I've messed with this stuff, so forgive me for not having specifics....
It has something to do with the High Voltage not bleeding off enough after shutdown. If you were to discharge the monitor you would see it instantly go away if I recall. So I would investigate the new flyback and it associated circuits leading to ground. (including the Focus/Screen potentiometer block)
Or possibly a color gun/neckboard grounding issue.

It's a residual HV thing keeping the phosphors lit up is all I remember at the moment.

Definitely goes away after shorting the anode to ground. No Screen/G2 voltage present about 10 seconds after shutdown... soo I guess it's time to go on a diode and resistor witch hunt? Visual inspection shows good solder joints all around.
 
I wouldn't. It's a non-issue. In fact, this has been discussed before, as to why it happens.

In a nutshell, it's just the guns firing off a last few electrons. They're in the center of the screen because the yoke isn't pulling them this way, and that.
 
Also, a G-07 doesn't have any "bleeder" resistors. It can store a charge for quite some time.

Edward
 
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