RetroHacker
Well-known member
Well, I finally got a "round tuit" and started working on my Gorf. It's been sitting, awaiting resurrection - and today I decided to actually tackle it. It had a lot of issues when I got it:
http://forums.arcade-museum.com/showthread.php?t=90713&highlight=gorf+galactic
But now, I've got everything pretty much working. I replaced all the caps on the power supply (as well as two diodes), and got the voltages back to where they should be, and steady too. Disassembled the card cage and thoroughly cleaned the backplane, and all the card edge connectors. The game no longer locks up and resets, and I fixed the bad RAM.
The speech was always really weak - much softer than any of the other sound effects. I replaced some of the components on the audio board (two toasty 330 ohm resistors), and cleaned the pots. Both audio channels are working properly. But, the speech was still really quiet - almost impossible to hear. Originally, if you listened closely, you could hear it talk, and it was working fine. But now, now that I've got everything else working, the speech is no longer correct. All I get are a few random syllables - no words. Every time it's supposed to say something, I hear.. something - quietly - but just fragments and bits.
I have a "spare" boardset with issues (bad RAM card, bad pattern board, no speech), and I've tried swapping around boards, just for the heck of it. Swapped the CPU and the ROM board, no effect. I swapped in the other GAME board, but that one is clearly faulty - no speech at all with the spare board. Swapping the SC01 between the boards doesn't do much - the bad board produces no speech regardless of which chip it has, and the "good" board won't produce any speech with the SC01 from the bad board. So, the bad board has a bad SC01, as well as something else wrong with that circuit.
So, before I start digging deep into the sound circuits of Gorf, anyone have any pointers?
-Ian
http://forums.arcade-museum.com/showthread.php?t=90713&highlight=gorf+galactic
But now, I've got everything pretty much working. I replaced all the caps on the power supply (as well as two diodes), and got the voltages back to where they should be, and steady too. Disassembled the card cage and thoroughly cleaned the backplane, and all the card edge connectors. The game no longer locks up and resets, and I fixed the bad RAM.
The speech was always really weak - much softer than any of the other sound effects. I replaced some of the components on the audio board (two toasty 330 ohm resistors), and cleaned the pots. Both audio channels are working properly. But, the speech was still really quiet - almost impossible to hear. Originally, if you listened closely, you could hear it talk, and it was working fine. But now, now that I've got everything else working, the speech is no longer correct. All I get are a few random syllables - no words. Every time it's supposed to say something, I hear.. something - quietly - but just fragments and bits.
I have a "spare" boardset with issues (bad RAM card, bad pattern board, no speech), and I've tried swapping around boards, just for the heck of it. Swapped the CPU and the ROM board, no effect. I swapped in the other GAME board, but that one is clearly faulty - no speech at all with the spare board. Swapping the SC01 between the boards doesn't do much - the bad board produces no speech regardless of which chip it has, and the "good" board won't produce any speech with the SC01 from the bad board. So, the bad board has a bad SC01, as well as something else wrong with that circuit.
So, before I start digging deep into the sound circuits of Gorf, anyone have any pointers?
-Ian
