Wells Gardner K7400 25" problem

Hammerfist

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Hi guys! First post here, but I've been reading the forum for some time and I really like the enthusiasm here! Nice to see other people so interested in this hobby :) But on to my issue at hand:

Just got a Namco 20 year reunion cab yesterday. It has WG K7400 25" monitor, which has a problem that I'll do my best to describe:

When I first went to see the cab, it was turned on and had this white bright line going from top to bottom. So there was no picture of the game (which could be heard running). I then turned it off, and after a few minutes, turned it back on and the picture came out ok. After few minutes, the white line came back. Regrettably I didn't take a picture of this and after taking the cab home, I haven't been able to reproduce THAT specific problem. I've tried to keep the monitor on for few minutes, but maybe it needs more time, which I don't want to give it at the moment, to prevent further breaking something. And from here, we come to my other "evidence" :

The three attached pictures represent three components (and in one case a lightly darkened part of the pcb) that I discovered today. I haven't yet discharged and/or removed the monitor from the cab, since I thought it's best to start by asking for known problems.

Here are two videos with the symptoms:

1. http://www.youtube.com/watch?v=kNnvTCyn4-Q
This video shows, how it takes a while for the monitor to "charge up" as you can see and hear. As you can see later in the video, the picture waves from side to side slowly.

2. http://youtu.be/hHLOhPV7GYY
Here you can hear the sound the monitor makes. Sounds quite the same as some CRT TV's I've had, but much louder and not as healthy.

If you need more info, let me know and big thanks for all the help!
 

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starting with the pictures....the first and last pic are normal as for the second pic, I've never seen that small transformer gooped up with what looks like silicone. I can only guess someone thought it would reduce the whinning sound you mention from the video.
The age of this chassis calls for a cap kit which I'm sure you've read in alot of posts around here. This would take care of the of the ripple you see on the screen and it may shorten the length of time it takes to produce a picture at start up....but these do take some time to warm up and is normal. This may also reduce the sound you hear from the second video but you may hear it even after doing the cap kit. You will probably be told to replace the flyback but I would leave it alone as it seems to be working fine.....good luck.
 
Ok, big thanks for the info cbuschief! Will start looking for those caps now.

While your chassi is out check for any hairline fractures above and around the focus on the flyback transformer. I was hesitant to replace mine, but did did anyway as per some of the other monitor experts.
 
The line you described is vertical collapse. Since it comes and goes, the hope is that it is caused by cold solder or a broken trace. If you still get it after a recap and solder go-over, then the next step would be to check D302, R303, and U601...
 
The line you described is vertical collapse. Since it comes and goes, the hope is that it is caused by cold solder or a broken trace. If you still get it after a recap and solder go-over, then the next step would be to check D302, R303, and U601...

Ok, thanks for the info :)
 
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