G07 CBO problems

jeljr2003

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I have a recently recapped and fly back changed and all pots including B+ on a G07 CBO in a Pacman cocktail. Everything was working perfectly fine until the whole arcade just died ( main 2a slow blow fuse blew) unplugged monitor replaced fuse game plays fine blind. Now to the G07 chassis. Remove both fuses and they were fine check big white resistor and it's fine checked FR901 and FR401 both check fine. No noticeable cracks or anything on fly back. Check HOT and Voltage reg as well everything is ohm and diode within specs. All parts came from arcade parts and repair. I'm at a lost any suggestions or guidance would be greatly appreciated and my grandkids would be very happy as well.
 
I have a recently recapped and fly back changed and all pots including B+ on a G07 CBO in a Pacman cocktail. Everything was working perfectly fine until the whole arcade just died ( main 2a slow blow fuse blew) unplugged monitor replaced fuse game plays fine blind. Now to the G07 chassis. Remove both fuses and they were fine check big white resistor and it's fine checked FR901 and FR401 both check fine. No noticeable cracks or anything on fly back. Check HOT and Voltage reg as well everything is ohm and diode within specs. All parts came from arcade parts and repair. I'm at a lost any suggestions or guidance would be greatly appreciated and my grandkids would be very happy as well.
I'd take a close look at the bridge rectifier or maybe a cracked solder joint around the flyback. G07s can be sneaky like that.
 
I agree with other ideas so far. What is the B+ voltage, if it's zero, and both fuses are good, what is the VAC at the monitor plug? Show us pics of the top and bottom of the chassis when you get a moment.
 
B+ voltage before failure was set at 120v. Unable to test now since main fuse blows every time I connect monitor. Unfortunately, I only had a few 2 amp slow blow fuses and now I have to wait for Amazon delivery tomorrow. So I can check plug voltage coming out of isolation transformer. Hopefully, it's just a bad isolation transformer which I wanted to replace anyway since whoever had this before me installed a regular isolation transformer and not the correct MT0085 which has the dual voltage 120v and 12V. However, I haven't had much luck finding one thus far. I'll try to get a few pictures of the chassis but I have to figure out how to make file size smaller so I can upload them.
 
Buy a rebuilt one so you can muck with this one in your leisure. The gkids grow way too fast get that thing running STAT.
 
B+ voltage before failure was set at 120v. Unable to test now since main fuse blows every time I connect monitor. Unfortunately, I only had a few 2 amp slow blow fuses and now I have to wait for Amazon delivery tomorrow. So I can check plug voltage coming out of isolation transformer. Hopefully, it's just a bad isolation transformer which I wanted to replace anyway since whoever had this before me installed a regular isolation transformer and not the correct MT0085 which has the dual voltage 120v and 12V. However, I haven't had much luck finding one thus far. I'll try to get a few pictures of the chassis but I have to figure out how to make file size smaller so I can upload them.
there are 2 fuses. F901 is the smaller one connected to the deflection side, F902 is the larger one connected to the power side. neither are slow blow and neither are 2A, so I don't know where you obtained that information from. lol for posterity F901 is 1.25A fast, and F902 is 3A fast. you can find these easily at the APAR site just searching the fuse locations.

if you're blowing F902 that would most likely suggest you have a shorted diode in the bridge rectifier and this is commonly achieved by connecting a hot chassis like the G07 without an isolation transformer and with earth ground connected. you've effectively shorted the hot and neutral connections together through the bridge rectifier in that instance.

if you're blowing F901 the most common failure is a shorted horizontal output transistor (HOT) or bad flyback. the HOT is the frame transistor mounted on the wall on the flyback side. it's not socketed, you have to manually solder the wires to the transistor legs. flyback failure will either be you just bought a dud replacement, which happens, or you installed a cap kit and didn't replace the flyback and it just crapped out spectacularly.

this is an obligatory mecha "I need more information" post, but I think I covered the most frequent scenarios that happen with these
 
there are 2 fuses. F901 is the smaller one connected to the deflection side, F902 is the larger one connected to the power side. neither are slow blow and neither are 2A, so I don't know where you obtained that information from. lol for posterity F901 is 1.25A fast, and F902 is 3A fast. you can find these easily at the APAR site just searching the fuse locations.

if you're blowing F902 that would most likely suggest you have a shorted diode in the bridge rectifier and this is commonly achieved by connecting a hot chassis like the G07 without an isolation transformer and with earth ground connected. you've effectively shorted the hot and neutral connections together through the bridge rectifier in that instance.

if you're blowing F901 the most common failure is a shorted horizontal output transistor (HOT) or bad flyback. the HOT is the frame transistor mounted on the wall on the flyback side. it's not socketed, you have to manually solder the wires to the transistor legs. flyback failure will either be you just bought a dud replacement, which happens, or you installed a cap kit and didn't replace the flyback and it just crapped out spectacularly.

this is an obligatory mecha "I need more information" post, but I think I covered the most frequent scenarios that happen with these
I was referring to main cabinet 120v fuse the fuses on monitor chassis are good in fact everything checks out good on monitor chassis so far, but when I get more main power fuses I can verify if isolation transformer is outputting 120v. Then I will know if it actually a problem with monitor or transformer.
 
Buy a rebuilt one so you can muck with this one in your leisure. The gkids grow way too fast get that thing running STAT.
Any good sources for a rebuilt chassis? What's a good ballpark price for one? This is the only arcade I have so far but I will be adding to it for the grands it great for them to experience retro arcade games instead of PC and PS5. They were loving playing this one although was short lived until it died. Lol
 
I recommend this guy:


Best price around too.
 
I recommend this guy:


Best price around too.
💯
 
Any good sources for a rebuilt chassis? What's a good ballpark price for one? This is the only arcade I have so far but I will be adding to it for the grands it great for them to experience retro arcade games instead of PC and PS5. They were loving playing this one although was short lived until it died. Lol
Mecha gave my suggestion. 😀
 
for troubleshooting I always use circuit breakers. fuses after problem solved
I'll have to check on that didn't know they offered circuit breakers that would fit in fuse holder. Or do you de solder wires from fuse block and attach to CB? Sorry I'm new and don't know all the tools and tricks yet. Lol
 
I usually use jumper wires since it is temporary and only during troubleshooting, otherwise it would not be a safe long term solution unless I came up with a permanent mounting
 
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