The following is a list of monitors which SHOULD work with a 3xx or 6xx player or Mac/PC CDi Authoring board RGB port. It is not definitive and should be used only as a guide. We have only tried a few of these here. You should consult with your vendor to make sure the monitor you choose is compatible with NTSC RGB! (Or, in Europe, PAL RGB). It is also preferable if the monitor has separate BNC inputs for Red, Green, Blue, and Sync. We have an adaptor available for this type of monitor.
And the monitors are:
Sony:
PVM-1340, 1341, 1342Q, 1344, 1354, 1390, 1942Q, 1944, 1954Q, 2030, & 2530
GVM-1310, 2020

Panasonic:
BT-M1310Y, BT-H1350Y, BT-D1920Y, DT-2700MS

JVC:
VM-R140SU, VM-R190SU

And of course, the ever popular Magnavox 1CM135. Now out of production?