Repair help needed: Time Pilot

[antron]

So I picked up a partially working (maybe) Time Pilot that looks exactly like this:

The seller thought it might be a boot, but it looks just like one on this Centuri dedication page.

The only problem seems to be that it won't sync. I am suspicious that it is a boot because pinout records on the net show TP bootlegs with the colors and sync rearranged. I measured the resistance back through the video outputs looking for a pattern that might fit three colors and a sync, and it appears to follow the arrangement of an official Konami pinout.

I also tried to follow the traces to see where they go. I'm not sure, but the one I think is sync may go through some resistors to a NAND gate, and the colors through some resistors to memory chips. Does this sound right? Are colors generated this way? I expected an op-amp or specialized video output IC.

Any help would be much appreciated.

Added:
I just now noticed "Taimu-Paylot" in the corner, lol, my board has it to.

From an old KLOV thread about "Taimu-Paylot"

Bootleg of "Time Pilot"...
It probably will come up as "Space Pilot" if it works -- standard Konami pinout.

[system11]

An oscilloscope would be really handy...

You're going to have to just trace the sync signal back and see where it goes, you'll need a logic probe at the very least or there is zero hope of diagnosing what is probably a fairly simple issue.

A lot of bootlegs are near enough straight clones, it may be worth seeking out the Time Pilot schematics and seeing how they compare tracing the sync on those and your board as a comparison.

[antron]

O-scope is possible.

I think I must have made a mistake in the tracing I did so far, as the memory chips I found are read only*. Good idea on using Time Pilot schematics, as this boot looks almost identical to a Konomi one.

I general, how were video color signals generated back then?
The sync should lead to some type of logic gate, right?

First I need to know if this thing really is Konami pin compatible. I might just need to swap some wires in the cross-board ribbon cable, as all 4 video signals go through it.

Thanks

* is that because all possible levels were predetermined?

Edit:
Got the Time Pilot schematics. Mine appears to be pin compatible with standard Konami. And the video is generated with a resistor network connected to a PROM, so I did follow the trace correctly.