[ukvac] Re: Tech : JAMMA Cab - No Sound or Coins
check that the wire feeding GND to your coin inputs (if you have old S10
type mechanical coin slots) and the GND feeding the speaker. It sounds
likely that one GND wire might be used to feed the speaker and coin iputs
and has somehow dislodged from its GND point.
If you have Sentinel, or Mars electronic coin mechs then the problem may
just be with a loose plug.
on the jamma connector, the speaker output and coin input are not directly
related. It might be just how your cabinet is wired that you now have
neither sound nor coin acceptance..
the reason i mention this relationship is because to hear sound from a JAMMA
PCB, you need only take the output from the top pad of the edge connector
(sound +) and run it to a speaker, the other contact of the speker being
attatched to GND. If every manufacturer followed the JAMMA standard to the
book then 100% of boards would work like this, it appears though that some
bootleg games, and games from certain companies do not, ie FABTEK (Raiden)
being one example, where the top pad is actually sound -, and the bottom is
sound +. most older cabinets (1980's) just simply have the speker hooked up
to either sound contact from the edge connector which i suppose is the
easiest and most compatible solution, however, if for some reason they were
skimping on wires, you can get away with just running the Sound + to the
speaker, then grounding the other side of the speaker (usually in the front
of the cabinet) from the control panel or coin mechs.
Put your original PCB back in and see if that works..
seeya!
==========================================================
Andy Welburn - A Collector of fine video game antiquities
http://www.willowsp.u-net.com/andy/collected.htm
>> CURRENTLY MOST WANTED <<
ATARI Battlezone AVG and AUX Logic Game Boards
==========================================================
check that the wire feeding GND to your coin inputs (if you have old S10
type mechanical coin slots) and the GND feeding the speaker. It sounds
likely that one GND wire might be used to feed the speaker and coin iputs
and has somehow dislodged from its GND point.
If you have Sentinel, or Mars electronic coin mechs then the problem may
just be with a loose plug.
on the jamma connector, the speaker output and coin input are not directly
related. It might be just how your cabinet is wired that you now have
neither sound nor coin acceptance..
the reason i mention this relationship is because to hear sound from a JAMMA
PCB, you need only take the output from the top pad of the edge connector
(sound +) and run it to a speaker, the other contact of the speker being
attatched to GND. If every manufacturer followed the JAMMA standard to the
book then 100% of boards would work like this, it appears though that some
bootleg games, and games from certain companies do not, ie FABTEK (Raiden)
being one example, where the top pad is actually sound -, and the bottom is
sound +. most older cabinets (1980's) just simply have the speker hooked up
to either sound contact from the edge connector which i suppose is the
easiest and most compatible solution, however, if for some reason they were
skimping on wires, you can get away with just running the Sound + to the
speaker, then grounding the other side of the speaker (usually in the front
of the cabinet) from the control panel or coin mechs.
Put your original PCB back in and see if that works..
seeya!
==========================================================
Andy Welburn - A Collector of fine video game antiquities
http://www.willowsp.u-net.com/andy/collected.htm
>> CURRENTLY MOST WANTED <<
ATARI Battlezone AVG and AUX Logic Game Boards
==========================================================