WG6100 C901 100uf 50v Cap Popping! HELP!

barakawins

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WG6100 Fix History - Caps Popping, No HV - Fixed!

OK.. I'm working on a Star Wars. Got the board up and running. Now for the monitor. This monitor originally had a fried resistor R903 (3.9Ohm). I replaced it with the proper value. Picture started to come up and then POP! C901 100uf 50v cap pops. Installed another one and then a minute later, bang! Explodes again....... Basically the top of the cap opens and pops. Anyone know the fix for this? Driving me nuts! I know the cap is in the right way. All other caps were replaced correctly as well. Any ideas?

Thanks

John
 
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hMMMMMMMMM

Q900. When I look in the HV Cage, there are only 3 wires there but no transistor. Is there supposed to be a transistor there? Anyone have a pic of Q900 in that HV Cage?

John
 
Learn how to use a multimeter? Don't just change parts. Test them to see if they are bad. If it was bad, then you change it. If it's not, you look elsewhere. What about those other parts? In fact, check every diode and transistor on the board...
 
BTW - if you're blowing F600 and F700 too, then check those transistors and diodes on the deflection board also, especially the four transistors behind them on the heat sinks and the diodes next to them...
 
555 timer on HV Cage

I think I found the culprit. There is a 555 timer which is responsible for charging capacitors. I think this timer is not working correctly and causing the cap @ C109 100uf 50v to pop. This timer also discharges. I'll change out and report after the weather breaks!
 
Please go back to the link that modessitt posted and go to page 19 "Tempest Display Troubleshoot (Flowchart)". Follow that flowchart and it will likely help you identify your issue.
 
flow chart

Yeah.. I saw the flow chart. However, the wrong fuses were popping. The ones popping are F600 and F700. These aren't mentioned on the cart. Seems like the C109 cap is popping and then these fuses blow. Anyway, I'll report back after replacing the timer.

John
 
...so then you would take the right hand path of the chart, right? And start with "Turn up brightness and contrast controls on HV pcb..."
 
WG6100 Getting Better! Update!

OK..

Previous symptom. F600 and F700 3 amp fuses popping on startup. Leaving the game on loner took out C901 cap in the HV Cage.

Fix: Remove deflection transistors (6) mounted to the cage and test for shorts. Out of 6, 4 were found to be shorted.

Result: No more 3 amp fuses popping and cap is stable.

Now: Spot killer is on and no High Voltage. Back to the drawing board.
 
Check the diodes under the big white resistors to see if they are open or bad. Just a long shot. When I redo 6100s, I check just about every single component. It is amazing how many wrong parts are installed from previous fixes or how many resistors are open, wrong value and so on. I have a repair log for one 6100 monitor that is 3 pages long. Took me almost 9 hours to repair. I know that seems like a long time but fixing a bad component and then retesting take a long time to install/remove etc. Seems like once you fix one thing, you find another bad or wrong part to replace.
 
Finally - WG 6100 up and running!

LV2000 board installed in the chassis previously to my owning was the problem.
The 3 legs that fit into the deflection pcb became loose! That was it. Soldered back on and heard the 6100 beast come to life! Hope this post helped someone!

John
 
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