TrevEB
Member
Joust with 3 invisible horizonal lines & flimsy joysticks
I have a joust that has three invisible lines running horizontally across the screen.
When the ostrich passes through it, the lance doubles. The graphics also get screwed up.
What I know so far.
1. There are ram issues. Sometimes the ram all checks out fine, sometimes random chips fail. It's rarely the same number. I'm assuming the best route here is to just replace all of them if I can.
2. Voltages: (taken from the molex connectors)
Main board: -5.07, +11.89, +5.18, +11.89
Rom board: +5.17, +5.17
Sound Board: +11.97, +5.14, (pin 8 = -5.07)
Pin 8 should be -12vdc according to the schematics.
Thats way off, but it is on the sound board.
Seems unlikely that it would cause visual problems.
Are the other voltages close enough?
(updated)
The power supply was switched to a modern unit many years ago. The old transformer at the base of the cabinet is still connected to the fluorescent bulb, the security off switch and the power cord.
3. Its not the monitors fault. I have a new monitor installed. The old one actually has the lines burned into it.
4. all of the rams, roms and other chips have been pulled, cleaned and reseated.
Rams were relocated in a different order. This does not appear to have relocated the invisible horizontal lines.
Question 2
The joysticks seem weak, like they should have springs but the springs are gone.
Review the picture and let me know if I'm missing something.
I have a joust that has three invisible lines running horizontally across the screen.
When the ostrich passes through it, the lance doubles. The graphics also get screwed up.
What I know so far.
1. There are ram issues. Sometimes the ram all checks out fine, sometimes random chips fail. It's rarely the same number. I'm assuming the best route here is to just replace all of them if I can.
2. Voltages: (taken from the molex connectors)
Main board: -5.07, +11.89, +5.18, +11.89
Rom board: +5.17, +5.17
Sound Board: +11.97, +5.14, (pin 8 = -5.07)
Pin 8 should be -12vdc according to the schematics.
Thats way off, but it is on the sound board.
Seems unlikely that it would cause visual problems.
Are the other voltages close enough?
(updated)
The power supply was switched to a modern unit many years ago. The old transformer at the base of the cabinet is still connected to the fluorescent bulb, the security off switch and the power cord.
3. Its not the monitors fault. I have a new monitor installed. The old one actually has the lines burned into it.
4. all of the rams, roms and other chips have been pulled, cleaned and reseated.
Rams were relocated in a different order. This does not appear to have relocated the invisible horizontal lines.
Question 2
The joysticks seem weak, like they should have springs but the springs are gone.
Review the picture and let me know if I'm missing something.
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