Newbie : Arcade VGA - J-Pac Problems

Archived from groups: alt.games.mame (More info?)

I have just aquired a brand new cabinet and bought a Aracde VGA and J-Pac
and have problems.

The problem is the Sync OK LED is off and a jumbled picture on screen. The
problem is described on the Ultimarc site as follwos:

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When the SYNC OK LED is off, this indicates that no sync signal is being
sent to the monitor because it is out of the correct range for the monitor.
The effect this has on the monitor varies with different monitor types. Some
monitors have an in-built line timebase which will free-run at its natural
frequency, hence a jumbled picture will be displayed. This will NOT cause
any damage as the monitor is not being driven outside its range. If a 15Khz
monitor is being used and both the 15 and 31 jumpers are on, the J-PAC will
generate it's own "dummy" 15Khz sync signal if it is not receiving any sync
from the PC (for example if the PC is re-booted).
______

So, anyone know the solution?

[PS - I have posted on the Ultimarc Forum but cannot see my post as yet]