Monday, 20 January 2014

Shinobi - Repair Log

Shinobi - Repair Log

Thanks to a supreme act of kindness of a very kind gentleman (who works next door) I am now in possession of an absolute classic..! (He also happens to run a rather good 8bit Sega preservation site)

The seminal 1986-'87 Sega p.c.b. Shinobi \o/ 


Much <3 for this game! Thanks again dude, insanely kind of you ..I'll get her working again.

In fact, I actually managed to on the same night I recieved the board. :D 
(eager would have been an understatement)

First port of call: several physically broken capacitors on the top ROM board:
Desoldered all four smoothing-caps from the top ROM board:


Found 220uf replacements in the parts box.. they are a little larger / high rated, but they will work nicely.

 Like so:
Still no luck though.. this wasn't enough to bring the board back to life..

So I next assumed the encryted CPU's battery had run dry, and lost it's memory..

So swapped out the CPU for a stock 68000 processor:

..burned a pair of replacement unencrypted program ROMs.

But still now picture! :'(

Probing the video output pins with the scope showed that the RGB was working, 
but the SYNC line was static.. nada! 

Following the trace from the SYNC pin, round the edge of the board lead to this tiny scratch.. 

Under the microscope.. It's a clean break, we have a winner.


I soldered over the break, but thought it a bit weak.. 

So fitted a thin green wire that bypasses the cracked trace.

Which ran from the Jamma connector:


Right across the pcb - to the other end of the cracked-trace:

And once the little power was applied....

\o/ Shinobi lives again :D


 An absolute classic game! Hard as nails of the highest difficulty setting!!

Hopefully this game will last another 26 years to come :)