Sanyo 20ezv vertical collapse help

dyno

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Working on a Sanyo 20ezv monitor for my playchoice 10 and the vertical adjustment will not adjust fully and there is a line down the middle of the screen. I have done a cap kit and replaced transistors 402 & 403 for the vertical circuit. Also occasionally the screen bounces. Any ideas of where to go with this ?
 

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Couple more simple things to check:

1. Loose or cracked solder joints where the yoke wires connect to the chassis. (particularly near the vertical windings)
2. Double check your neck board for any cracks or cold solder.
 
Make sure you have good continuity on your yoke connector and pins. Make sure you have good continuity all the way from the solder joint all the way up to the yoke winding.
 
So finally had time to look at the chassis board and no cracks, solder joints look good. Next step will be to start checking individual parts of the vertical circuit like resistors and diodes
 
Check everything per the flowchart posted. Check the vertical sync and vertical size pots. Replace if bad. Ensure that both of your vertical IC's are completely secure and screwed down. Make sure that the heat sinks are soldered in place properly. Any of this being loose, cold solder, etc can cause collapse. Check for cold solder joints everywhere. These chassis are prone to that as well as being incredible fragile and break easily.
 
So I finally pulled the monitor from the cabinet and have an extra Nintendo power supply to power the monitor up. This is what I am getting, I am able to adjust the screen size vertically to fill the whole screen area but get the line down the middle. I checked all the components from the flow chart posted and all tested good. The power at J7 was just under 16V. I have looked the chassis over and found no cracks in the chassis itself. Kinda stumped at this point
 

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Tonight I checked the voltages on the pins for IC401 , pin 19 was over 12v when it should be 1.65v. I check the resistors in line with pin 19 and they were both good. I didn't have the game board plugged in and it appears pin 19 is part of the sync circuit . Would that reading be high because no game pcb was plugged into the monitor or is the IC possibly bad ? That is as wide as the picture will go when adjusted vertically and there is still a line down the middle of the screen, just hard to tell from the picture.
 

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Things have gotten worse . I went through the chassis and did some resoldering for cold solder and now I have vertical collapse and IC401 is missing voltages on some of the pins
 
UPDATE **FIXED** Just an update , I have solved the vertical collapse issue and thought I'd share incase someone else runs into the problem. Capacitor 410 can be installed two different ways, I should have paid attention to how it was installed when I removed it when replacing the capacitors. When I re-installed cap 410 I put it back with the terminals in the opposite positive and negative positions from when I removed it. After going over the board and re-soldering everything with no fix , I noticed that cap 410 can be installed two different ways. I checked the 20 ezv chassis in my Popeye cabinet and noticed I had installed cap 410 in the wrong positive and negative positions. Once I fixed that my vertical collapse is gone. Thank you to everyone for all your help with this. Now my Playchoice 10 is back up and running :)
 
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