Hi All, I am currently working on a Golden Tee 99 board, trying to get it to wake up. It's one of those "untested" ebay purchases. When I got the board I did an inspection and comparison of other pics of the pcb and also matched it to my Golden Tee 98 which looks to be a nearly Identical board. The first thing I noticed is one of the caps was missing. There are only 2 caps on this board so I replaced them both (I thought it was an ace in the hole) I also unbent some of the pins on the connectors to make sure nothing was shorted. Anyway I am connecting the board and setting the power as per the manual (about 5.5 VDC) all 4 switches on SW1-Dip all on, and SW2-Dip 1&2 on and 3&4 off.(per GT99 manual) Only Jamma edge connector is attached to the board, no trackball or anything else. And when I turn it on only the yellow "sound status" light blinks. The green "video status" light is dark. Here is a full shot of the board.
Back of the board
I have looked this board up and down and do not see any broken traces or anything visible at all. I have removed and re-seated every socketed chip on the board. (and cleaned its socket with IPA) I also tried swapping these 2 chips from my working GT98 board, and it made no difference:
The reason I swapped those chips is because I know from troubleshooting my GT98 that if they are not plugged into the board you will get no display and no green light and no display. So I know the problem is likely not the chips. I went through and re-flowed the solder on those 2 sockets in case there was a cold solder joint but no luck I see 5v on pin 1 of those 2 chips as well when the board is on. I'm at a loss what to check next. I have also checked voltages from other chips on the board and I am getting power with the right voltages... I am thinking that whatever is wrong it may not be something visible. I cannot find any scratches or problems on the back either, the board appears to be in really good condition. I also connected speakers to the jamma harness to see if the game was playing blind but it is silent even thought the audio light is blinking. And I know my rig is working (I have tons of other jamma boards I can connect that work.) And power must be sufficient, or the GT98 board would not work... (again they look like the same board with different roms) I even went as far as checking prom0-3 with my eprom reader and they all read just fine...
The manual even mentions this problem and gives 2 things I already checked and one cryptic message about U1
I have been staring at this board for a half hour and I cannot find U1....
I am at a loss what else to check, any ideas on what components could fail related to video on these boards? Any help greatly appreciated.
Back of the board
I have looked this board up and down and do not see any broken traces or anything visible at all. I have removed and re-seated every socketed chip on the board. (and cleaned its socket with IPA) I also tried swapping these 2 chips from my working GT98 board, and it made no difference:
The reason I swapped those chips is because I know from troubleshooting my GT98 that if they are not plugged into the board you will get no display and no green light and no display. So I know the problem is likely not the chips. I went through and re-flowed the solder on those 2 sockets in case there was a cold solder joint but no luck I see 5v on pin 1 of those 2 chips as well when the board is on. I'm at a loss what to check next. I have also checked voltages from other chips on the board and I am getting power with the right voltages... I am thinking that whatever is wrong it may not be something visible. I cannot find any scratches or problems on the back either, the board appears to be in really good condition. I also connected speakers to the jamma harness to see if the game was playing blind but it is silent even thought the audio light is blinking. And I know my rig is working (I have tons of other jamma boards I can connect that work.) And power must be sufficient, or the GT98 board would not work... (again they look like the same board with different roms) I even went as far as checking prom0-3 with my eprom reader and they all read just fine...
The manual even mentions this problem and gives 2 things I already checked and one cryptic message about U1
I have been staring at this board for a half hour and I cannot find U1....
I am at a loss what else to check, any ideas on what components could fail related to video on these boards? Any help greatly appreciated.