Mitsubishi 50" Junk.. Ideas Welcome?

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MITSUBISHI 50P-GHS9 in a Sega Jambo Safari is off convergence.. surprise! I have remote and nothing will converge. It will change size etc but no color gun line will budge even though values are changing. Any Ideas? Is it the conversion board? IC's or is this junk toast.
 
My first impulse is "convergence ICs". RPCRTs have giant specialized ICs that maintain and tweak the convergence of the three tubes, and they have a tendency to cook themselves. They're usually $20-30 a crack, worth a shot IMO. Look for big black ceramic blocks with lots of legs, mounted on heatsinks.

Is the picture solid, i.e. none of the colors look curved or warped? It may just be a cold joint near one of the convergence ICs and it's not getting the signal from the main controller.
 
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MITSUBISHI 50P-GHS9 in a Sega Jambo Safari is off convergence.. surprise! I have remote and nothing will converge. It will change size etc but no color gun line will budge even though values are changing. Any Ideas? Is it the conversion board? IC's or is this junk toast.

I'm not familiar with this model however I would presume a
convergence IC is bad. Most projection CRTs have a service mode
where you can do a true convergence adjustment.

JD
 
My first impulse is "convergence ICs". RPCRTs have giant specialized ICs that maintain and tweak the convergence of the three tubes, and they have a tendency to cook themselves. They're usually $20-30 a crack, worth a shot IMO. Look for big black ceramic blocks with lots of legs, mounted on heatsinks.

Is the picture solid, i.e. none of the colors look curved or warped? It may just be a cold joint near one of the convergence ICs and it's not getting the signal from the main controller.

No the red is bowed in on the sides .. green is off square too. Is this still just the ICs? or other issues as well?
Thanks
 
if you're unable to adjust the convergence at all, I'm going to say it's a convergence IC failure. is this the same VGA type monitor, like for a Sega NAOMI? it's what we have in our 18 Wheeler and the convergence is 57 varieties of fucked up, but that wasn't why we had to pull the game, it was because it was shutting down to a red blur on the screen. that sounds like a cap thing.. one of these days I'll get around to tearing that thing apart.
 
Also note that for some models they have a handful of resistors around the ics (very close) that should be checked as well. But yeah 99% convergence ICs. I did my Mitsu 46" some time ago and its been working great since. The heat sink they were mounted to was ginormous and I considered a quiet 5" computer fan for it, but never got around to it.
 
if you're unable to adjust the convergence at all, I'm going to say it's a convergence IC failure. is this the same VGA type monitor, like for a Sega NAOMI? it's what we have in our 18 Wheeler and the convergence is 57 varieties of fucked up, but that wasn't why we had to pull the game, it was because it was shutting down to a red blur on the screen. that sounds like a cap thing.. one of these days I'll get around to tearing that thing apart.


Yes sir Naomi it is.. You have such an eloquent way to describe yours I cant wait to dig in.. i.e. 57 Varieties..
 
Also note that for some models they have a handful of resistors around the ics (very close) that should be checked as well. But yeah 99% convergence ICs. I did my Mitsu 46" some time ago and its been working great since. The heat sink they were mounted to was ginormous and I considered a quiet 5" computer fan for it, but never got around to it.

Cool thanks Ill check those too. If I had a quarter for everything Ive wanted to get around to, .... Well you know the rest.
 
No the red is bowed in on the sides .. green is off square too. Is this still just the ICs? or other issues as well?
Thanks

DEFINITELY convergence ICs. If they were just getting a bad/no signal the individual colors would still be square. Swap those puppies.
 
Convergence Transistors Good?

Check the fuse for convergence, axial type fuses in power supply board.
Take a picture of the chassis i will show where the convergence are at.
a aerial view over the left side board of chassis. also remove the board and check for bad connections to the transistors on the large heatsinks also.
If all the dynamic convergence is bad check the fuse's
If one color is wrong see that color parts only and 1-2 watt resistors around the convergence heatsinks, check are open or overheated all should be low ohms.
can compare readings between convergence colors.
Chassis should be around 1989 year special monitor from mits
Should have transistors for convergence amps,Let us know what you find.
 
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