That's great info, socks! My setup is DK PCB->JROK v4.1 + JROK Sync Cleaner->Component Output.
Now that I know much more about various sync types (much more than what I knew when setting up my direct feed), the sync cleaner is probably doing nothing. As far as I'm aware, it's purpose is to "scrub out" anything in the signal other than sync, primarily for use with sync on composite and sync on luma signals.
In my testing, most flat panels handle the component output fine. My DVDO IScan VP30 handles the component output fine. The OSSC, however, constantly loses sync. OSSC's tolerances are theoretically much tighter than those of the formers.
I've speculated that its either a jittery sync (like what us hobbyists are now correcting for on NES's and SNES's...wouldn't that be interesting if Nintendo's jittery sync dated all the way back to 1981... :p ), or out of spec voltage range. Sounds like you've found that it's the latter. Are you able to validate that with a scope (or possibly you already have
).
Dan - 12V can also be pulled off of the edge connector or any point up to and including the NIN2JAMMA. It's at pins 5 and E, going off of the classic pinout. If you're looking for a purely plug and play solution, you'd have to get something like a wall wart rated between 5v-12v, and route the barrel plug end into the cab. Beware, the GBS' barrel plug input is a somewhat less frequently used size.