WG4906 Fuse blows

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Repair Log on WG4906:

So got the monitor in the cab.

The connector was different then what I had, stripped the connector on the psu side and rigged it together for now.

Plug up the video connectors.

Attach ground to the frame.

Power on. Get image of garbled yellow can barely make out that this is not a Spider-Man Game PCB, it's an original Ninja Gaiden.

I rearrange the video connectors- still the same.

I notice that the monitor frame is getting warm- towards the leftside HOT i can feel a current. Thinking maybe it's not grounded well enough.

Take the ground off the outside part of the frame and attach it directly to the pcb chassis.

Power on and BLAM! there goes the f120 fuse, of which i have none atm.

My Theory- Monitor was indeed not grounded enough. The video connectors and ground wires attached to the pcb were incorrectly applied since i had been testing for an image- and when the monitor was properly grounded and turned on- it shorted due to those connections.

Am i on the right track there anyone?
 
The chassis will run with no external chassis grounds whatsoever. You just need to connect the DAG wire from the tube tot he neckboard. Ground on the video cable is necessary for a stable picture, but that's it.

Are you testing this through an isolation transformer? if not, then that would be an issue....
 
I am testing through the isolation transformer and The DAG wire is connected from the tube to the neckboard.

If the video ground is only neccesary for a stable picture, and that wouldnt cause a short, I am back to wondering why i was getting current flowing into the frame in the first place and why when I connected the ground to the pcb chassis- i got the short. I suppose thees could be unrelated.
 
My guess? A wiring fault. Check to make sure the outlet is wired correctly. Earth ground wired backward for neutral could be possible.
 
Do have some leads that are too long that are touching the frame underneath?

Is the chassis mounted in an original 4900 frame? Sometimes people alter a frame to get a chassis in that wasn't original to it. This can cause the chassis to mount too close to the tube - which could cause some current issues - or too close to the side wall....
 
Do have some leads that are too long that are touching the frame underneath?

Is the chassis mounted in an original 4900 frame? Sometimes people alter a frame to get a chassis in that wasn't original to it. This can cause the chassis to mount too close to the tube - which could cause some current issues - or too close to the side wall....

It has made that fuse blow for me as well.
 
Ok, I snapped a couple pics, maybe you can spot for a bad wiring.

But what do you know- the dang power cord is missing its ground!

Think this is why I had current running through the frame, only to short when i grounded it better?
 

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One thing that jumps out at me is the proximity of that ground wire on the right to the HOT - if that touches the outer case of the HOT - SHORT!!
 
You're on to something there- so the area of the frame i thought had current through it- was on the opposite side HOT- is it normal to feel current there near a HOT when the monitor is powered on? So, that's when I decided to ground the frame better and attach the ground to the pcb cage.

I'm a newbie, and this is my first monitor install- so I am definately prone to newbie errors here :)
 
The sides of the chassis are metal, and are bolted to the metal tube frame, so a ground wire to the tube frame is sufficient. get that wire away from the chassis.

And you could try unplugging the degauss connector. if there is a short in the degauss wiring, it could be shunting electricity to the frame...
 
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