[sdiy] Anybody a Sequential Sixtrak expert?

[mark verbos]

Hi guys,

I've had a friend's Sixtrak under the shelves in my shop for years. I'd love to get it working so that I can get it out of here. It doesn't seem like it should be that hard to fix, but I have had no luck. I like to forget about it for a while, then come back fresh.... no luck. Maybe someone knows some tricks that I don't.

I have worked on 3 other ones and they all look the same as each other in side, this one is totally different. The PCB is blue and has a bunch of flying wires on it. It's labeled "z-310 REV"  The OS EPROM  has a paper label on it that reads "© 1984SCI Trak 0-1"

When I power it up, a random number is on the screen and sometimes LEDs are on, the buttons do nothing. 

I don't see any clock hitting the CPU at pin 24, then I realized that there is no ICU123 on the board! That pin is tied to +5.

So, I'd love to see the schematic for this version, I'd love to get the EPROM data and burn a new OS chip. I'd love some kind of advice on what to do with it. 

Thanks.

Mark