Vision Pro Problem

ggames

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Greetings all,
I have a vision pro MTG 1901. All I can get out of it is a very small picture. The attached pictures are of a test pattern. Can anyone identify my problem? Anyone have a flow chart made up for vision pro?
Thanks
 

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That doesn't look like a "very small test pattern". It looks like you have no deflection and have the brightness cranked up. First turn down the brightness on the flyback until you can barely see a dot in the middle (so you can see that it is on). Then shut it off and check to make sure the yoke connector is hooked up. If so, unplug it and take ohm measurements between the red and blue wires, and the green and yellow wires.
 
Thanks modessitt,
What should I be or not be reading for resistance. You think I am shorted?
 
I'm reading 2.4 ohm on red-blue. 14.4 ohm on yel-grn. Shorted ?
 
I'm reading 2.4 ohm on red-blue. 14.4 ohm on yel-grn. Shorted ?

Yoke readings will vary geatly from manufacturer to manufacturer. Without comparing your readings with another MTG 1901.....it's hard to say if yours are correct. I will say.....your readings arn't unrealistic.

Edward
 
I found a cracked solder joint. Now I'm getting a bar.
 

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I fine toothed the solder joints. I'm suspecting the la7833 302. Not familiar with that. I saw the schematic, do you read it with a DMM the same way as a standard 3 legged transistor?
 
Sorta. Put on lead on ground somewhere and then touch the red lead to each leg using diode test. You'll either get no reading, a normal diode reading, or a short. If the short isn't a ground pin, then you need to replace it...
 
Got the la7833 chips and installed one. Immediately took out leg 3. Hmmmm. Thinking the IC regulator transistor Q802.
 
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