JAMMA fingerboards are basically edge connectors with the same pin layout as JAMMA arcade boards
The idea being, you take a non-JAMMA arcade board (or in our case PC or video console)
and 'convert' it to JAMMA by soldering the correct input/outputs to the JAMMA fingerboard
It should look something like this
All the JAMMA projects on this site use these fingerboards.
Buying Fingerboards
You should be able to get fingerboards from your local arcade distributor
or maybe even a local arcade (if you know someone in there !)
Check your phone book and try a few places
If you're having difficulty locating fingerboards, here are a few sources.
In The UK
Paul Swan's
(you're after 28 way 0.156" fingerboards)
Swallow Amusements
In The US
Louise's Harness Shop
100 Spring Street
Tuscumdia, AL 35674
Their number is
1-800-365-1941 or
205-381-6639.
(I've no idea if this place even still exists BTW)
Video Connection These may sell fingerboards
You could also try posting a request for JAMMA fingerboards on these newsgroups
rec.games.video.arcade.collecting
rec.games.video.arcade.collecting.marketplace