G05-801 problems

DP Louie

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I have a G05-801 that was dead that I'm trying to bring back to life. I did a cap kit and replaced the transistors on the deflection board, but the monitor was still dead. I checked the voltage going into the regulator board, it's at 32v, but there was nothing at the output pins. So, I replaced the 2 big caps (C100 & C101). Upon trying to power up the monitor, the cap at C806 on the deflection board blew up (stupid mistake - I installed it backwards). So I replace that, still nothing. I should have checked for voltage out of the regulator board, but I was in a hurry. I checked the transistor at Q101(2N6057) and it tested bad, so I replaced it, still nothing. The diodes at DB100 test good too. Any ideas? And yes, the fuses are good. :)
 
I'm presuming you get chatter and neck glow? Have you tried turning up the brightness?
 
Okay, I'm an idiot. I was checking the power output on the regulator board with my meter set on AC instead of DC. I now show 27v coming out of the regulator, but the monitor is still dead. Neck glow is good, but there's no chatter. The game (Asteroids) plays blind, and the spot killer led is not on. It would be on if the pcb's x/y output was faulty, correct? I have an o-scope, I guess now's a good time to learn to use it...
 
The first thing I would do is try and figure out why there's no chatter. I don't have a lot of experience with this monitor, but thought my questions might help you think of an answer. Keep us informed of your progress and resolution.
 
Trace back from the cap you installed backwards..if there's any resistors or diodes in line with it check them - recommended this same tip recently and someone found a burnt resistor from the backwards cap.

FYI - neck glow on a vector is different from any other monitor - the heater on the tube is powered directly from the game transformer so even if the monitor is totallly dead it'll still glow.

Last but not least...did you check ALL the fuses on the deflection board, AND did you resolder all pins on all the molex connectors on the deflection board when you did the cap kit? If not go back and nail em all.
 
Well, I finally hooked up my oscope to the board, and the x/y output is fine, looked cool on the tiny screen, lol. I'm stuck on the deflection board now - the fuses are all fine (picos) and I did reflow ALL the solder on all the pins, no signs of anything burnt due to the backwards cap, and I checked a couple of the resistors that were in line, they seem fine. The 801 faq seems to indicate that the HV diode is bad, but I'd like to verify that the deflection board is working first. Anyone know of a testing procedure? Or does anyone have a spare 801-05 deflection board for sale? ;)
 
Have you made any progress? I just replaced the transistors and all caps on my dead G05 and have the same symptoms. The game is playing blind, neck glow, but no chatter. :-(
 
Nope, no progress yet... I'm thinking it's a problem with the HV cage, as everything else seems to check out ok. I found this site, which details a modification to the HV cage. I think this is my next step. I'll post an update afterwards.
 
Good to know. Let me know what turns out. Mine is the G05-802 and I want to believe that I have a bad HV Diode. Just yesterday I placed an order with Arcade Shop for the diode as mine looks to be burnt somewhat. Without a HV Probe I cant be certain, so for the 12 dollars I figured why not. I found this site to be of some use: http://sites.google.com/site/3vmearcade/Home/g05-802
 
Well, I got the HV replacement kit installed, and the monitor is still dead... I'm sooo burnt out on this monitor! I have a bunch of other projects to work on, so I think this Asteroids is gonna be posted for cheap on craigslist. If anyone in central CA wants an early, owl eye Asteroids that plays blind for $100, lmk... :D
 
Well, I got the HV replacement kit installed, and the monitor is still dead... I'm sooo burnt out on this monitor! I have a bunch of other projects to work on, so I think this Asteroids is gonna be posted for cheap on craigslist. If anyone in central CA wants an early, owl eye Asteroids that plays blind for $100, lmk... :D

Don't give up, it will be 1 problem, and it's just you haven't found it yet :)

Are there any owners in your area with an Asteroids or LL who can do some board swaps with?

I have just been playing my vector games, so hang in there, it will be worth the pain
 
Just wanted to update this thread - thanks to Arcrevival this monitor is finally working! Arc offered to swap my monitor boards into one of his cabs that had an 801 to test them out. He touched up some of the solder on the boards and they tested fine in his monitor, so today I finally had time to put the boards back in, and the monitor looks great! So I guess I suck at reflowing solder :D. All this was due to a cold solder joint, probably the most common problem with these. Well at least this was a good learning experiance. And no, my Asteroids is not for sale... maybe a trade of some sort though. ;)
 
Glad I could help. Make sure you let them know it was free and I covered the return shipping for everyone that thinks I should never make a profit and I should put my money where my mouth is when it comes to saving games :)
 
Glad I could help. Make sure you let them know it was free and I covered the return shipping for everyone that thinks I should never make a profit and I should put my money where my mouth is when it comes to saving games :)

This is correct - I should have pointed this out. Arc refused any payment, and as stated he paid the return shipping! Thanks again Dave.
 
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