Monitor blowing fuses

DaveyPocket

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From what it looks like I have a WG4600 series or something, cant seem to find the label or it's in front of me and I don't see it... Anyway when I got this monitor the chassis fuse was already blown so I knew something might be wrong with it. I replace the fuse (extended the fuse holder as well), power the monitor on, power is on for about a half a second before the fuse on the isolation transformer blows. I was able to hear the high-pitched noise of the monitor when it was powering on, so it might not be completely dead. Anybody know of any possible issues???

Thanks
 
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Well, first ID the monitor exactly. Then unplug the monitor power to make sure the ISO fuse no longer blows. Then check the voltage from the ISO. Make sure there is no continuity between the input and output of the iso. Then pull the chassis and check for shorted diodes or transistors, popped caps, burnt parts, etc...
 
Well, first ID the monitor exactly. Then unplug the monitor power to make sure the ISO fuse no longer blows. Then check the voltage from the ISO. Make sure there is no continuity between the input and output of the iso. Then pull the chassis and check for shorted diodes or transistors, popped caps, burnt parts, etc...

The ISO is from my Pac-man machine which works fine, though I'll test again anyway. I attached pics of the monitor.
 

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Yep, it's a 4600. Pull it and check the VR and HOT for shorts. Look for burnt parts or popped caps. Rebuild, reflow, and retest...
 
So I've been testing parts, the HOT and VR and various other transistors check out one. I decided to test certain parts of the circuit. I disconnected the lead going from the large 30W resistor to the board, disconnecting power from the rest of the CRT. When I powered the CRT back on, it popped the fuse again. Form the is I believe the problem lies in this spot
726d9a7b.jpg
. Anyone else have any thoughts one what exactly the problem is? Replace all of the parts or what? And what about that giant white cylindrical thing that appears to be some type of transformer on the schematic? I heard those can go bad as well, but I have no clue what it is.
 
So I've been testing parts, the HOT and VR and various other transistors check out one. I decided to test certain parts of the circuit. I disconnected the lead going from the large 30W resistor to the board, disconnecting power from the rest of the CRT. When I powered the CRT back on, it popped the fuse again. Form the is I believe the problem lies in this spot. Anyone else have any thoughts one what exactly the problem is? Replace all of the parts or what? And what about that giant white cylindrical thing that appears to be some type of transformer on the schematic? I heard those can go bad as well, but I have no clue what it is.

Not sure which is the "30W resistor."

The giant white cylindrical thing, I think, is your line filter.

Have you tried unplugged your degaussing coil?
Have you check the rectified diodes for shorts?
 
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Replacement diodes arrived in mail today. Replaced all 4 diodes (X601 - X604). No more blown fuses! Monitor is up and running! Thanks for the help everyone!
 
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