Hi;
I recently picked up a ST SOS and have ended up spending about a dozen hours on it and it still has issues. It was sold to me as working and during the shipping, the monitor was damaged. I swapped a spare G08 into the game and checked all voltages. The game boots and goes into attract. I play a game, (works correctly), get killed and enter my initals. The following, (second) attract is messed up. Letters are missing from words, the score is missing numbers and the dividing red lines that seperate the various areas of the display are missing in areas.
The display is not all jumbled up and skewed etc. Just some information is "missing".
I shut the game off for 10 seconds and reboot, then when I press the one or two player buttons, it puts credits on the game. I have to flip the credit switch to start a game.
This is not the situation when the game is "cold", the credit and start buttons function as they should.
I pulled the switcher that someone hacked into the game and installed a fully rebuilt Sega linear power supply. I had to also replace the hacked wires in the harness. And then while the harness was out, repinned them all with Trifurcon pins to insure a proper connection.
I set the voltage a little on the high side, +5.12 but that did not help either.
Also, there is much oxidation on the board cage, spinner encoder wheel and the CP hardware, it's like hair is growing all over the place, (I'll post those pics later on).
I pulled all the boards and happy to say that they were not corroded. I reseated all the socketed IC's on the CPU and ROM PCB's but still have the same issues. Since the speech, sounds and drawing work, I think that the problem is either on the CPU or ROM PCB's.
Am I going in the right direction?
I'll video the situation and post a link later as well.
ANY positive suggestions would be greatly appreciated.
Thanks in advance.
Jeff
I recently picked up a ST SOS and have ended up spending about a dozen hours on it and it still has issues. It was sold to me as working and during the shipping, the monitor was damaged. I swapped a spare G08 into the game and checked all voltages. The game boots and goes into attract. I play a game, (works correctly), get killed and enter my initals. The following, (second) attract is messed up. Letters are missing from words, the score is missing numbers and the dividing red lines that seperate the various areas of the display are missing in areas.
The display is not all jumbled up and skewed etc. Just some information is "missing".
I shut the game off for 10 seconds and reboot, then when I press the one or two player buttons, it puts credits on the game. I have to flip the credit switch to start a game.
This is not the situation when the game is "cold", the credit and start buttons function as they should.
I pulled the switcher that someone hacked into the game and installed a fully rebuilt Sega linear power supply. I had to also replace the hacked wires in the harness. And then while the harness was out, repinned them all with Trifurcon pins to insure a proper connection.
I set the voltage a little on the high side, +5.12 but that did not help either.
Also, there is much oxidation on the board cage, spinner encoder wheel and the CP hardware, it's like hair is growing all over the place, (I'll post those pics later on).
I pulled all the boards and happy to say that they were not corroded. I reseated all the socketed IC's on the CPU and ROM PCB's but still have the same issues. Since the speech, sounds and drawing work, I think that the problem is either on the CPU or ROM PCB's.
Am I going in the right direction?
I'll video the situation and post a link later as well.
ANY positive suggestions would be greatly appreciated.
Thanks in advance.
Jeff
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