CGA to VGA converting question

[iscariot]

I have come into a few 21 inch nec monitors and was wondering about the signal used. Is it possible to just wire the jamma signal directly into these?  If not, what is the cheapest way to output using these?

Oh sorry I forgot to say these are 6 multisync and 4 apple studio 21 inch displays.

[SailorSat]

Basically it depends on the frequencies the monitors support.
VGA is 31kHz where CGA uses 15kHz. If the multisync go down to 15kHz you're fine.

Second thing is not every monitor supports "composite sync" which you get from your JAMMA board. You might need a "sync splitter" to get seperate syncs.

Third and last thing; You may need some resistors in your RGB lines, as JAMMA boards usually output signals up to 5V, where VGA usually only goes up to 1V.

[StephenH]

This converter will likely due the trick:

http://www.converters.tv/products/cga_to_vga/77.html