joust sync help

andyrew

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Does anyone out there happen to have a joust machine with the composite sync? i have one that was hand-wired together and it came apart and i can't get the sync back. i remember one of the wires was not connected on the chassis side and the 2 remaining wires were connected in some combination to the board on the door.

If anyone has this setup could you take a pic and send it to me, please? I need to see how the black, purp and purp/wh wires on the board are connected to the same wires going to the monitor chassis. the connector on the chassis has a jumper between the two sync wires.

thanks,
andy
 
https://www.google.ca/url?sa=t&rct=...sg=AFQjCNGCQSPGEqGE06UHZ9vfDqPOcGAayA&cad=rja

this link will start an auto D/L for a joust pdf

on page 20 of 26. on monitor black (ground) pin 4 on monitor, violet (purple) pin 5 monitor
violet -white pin 6 monitor.

on CPU connector IJ3 same page , left side on schematic black pin 4 , violet pin 5 violet-white pin 6. sound like the harness is kinda jacked up you may have to ping it out with a DMM to get it right. hope this helps.
 
Thanks for the info and the schematic but that's not my problem. My machine isn't a straight wiring from IJ3 to the monitor. When I got it it looked like someone had converted it to a composite sync. On IJ3, 2 of the wires were crossed and connected to one of the wires to the monitor, and the other wire was direct. I don't know which was which and can't figure it out now.

on P202 on the monitor chassis board, pins 5 and 6 are jumped together.

If you know how the composite sync was wired such that the 3 wires from the IJ3 go into the 2 on P202, that's what I need to figure out.

Thank you for the help.
 
Finally got it figured out. I just tried every possible combination of wires until i got it to work.

Now a new problem :) The sync is correct - it doesn't roll vertically or horizontally. But now the screen is off-center by a couple inches. When all this started i recapped the chassis. The h-hold will center if for a second, but then it'll drift off a little bit. It won't roll, it'll just move off-center. If I tap the h-hold it'll move a little and then settle off-center again.

Any idea what would cause this? as I said, i recapped it and cleaned it all up. could the pot be dirty? might the solder joint be loose? I don't know what else might cause this problem.
 
I think the game is outputting separate signals but it's possible that whoever owned the game before me modified it to use a composite sync signal as the purple and purple/wh from the game are tied together at the chassis. I couldn't get the game to work on a generic 4901 that i was using as a test, i had to put the original chassis back in.
 
I think the game is outputting separate signals but it's possible that whoever owned the game before me modified it to use a composite sync signal as the purple and purple/wh from the game are tied together at the chassis. I couldn't get the game to work on a generic 4901 that i was using as a test, i had to put the original chassis back in.

Could be.

Twisting those two wires together is the "cheap" way of trying to make composite SYNC and doesnt always work.
 
Wouldnt Joust be outputting separate +V and +H SYNC?

The last pin on the video output is combined sync (csync). There is also a trace (W1) which you can cut which inverts the sync by providing a high input to the 7486 XOR. It's pretty clear on the schematic.
 
The last pin on the video output is combined sync (csync). There is also a trace (W1) which you can cut which inverts the sync by providing a high input to the 7486 XOR. It's pretty clear on the schematic.

Ah yes, forgot about that.
 
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