Apple IIGS RGB Monitor How ot Hook up to test with a PC

Many Apple displays of about that timeframe used a DB-15 (two rows of pins) connector. Adapters to VGA (three rows of pins) are readily available from multiple sources that deal in older Mac equipment. The adapters shuffle the five crucial signals (Red, Green+Intensity, Blue, Horizontal-Sync, and Vertical-Sync) so that they line up on the correct pins for VGA. There is only ONE way to connect the five key signals that will produce a picture, and every adapter (that is not defective) will connect those signals correctly.

You must be careful to get an adapter that has the right male and female connectors. There are two main types, one intended to adapt Mac displays to VGA computers, and the other intended to adapt older Mac computers to VGA displays.

Mac adapters also provide a code on pins 4, 7, and 10 that tells the older Mac what class of displays is attached, If you plan on using this with a Mac later, you will need the right adapter, or one with tiny switches. The various adapters differ ONLY in the ID bits on pins 4, 7, and 10, not in the basic connection of the Video signals.

Nick,

There is no easy way to do this.

You're main obstacle will be converting the horizontal refresh rate. The IIGS monitor operates at 15.75KHz, while a computer's VGA output is 31KHz. Scan converters are out there, or at least they used to be back when there was demand for such a thing.

The easiest route would be to find a IIGS or contact a local Mac (or Apple II) user group for help.

John

I recall being told that there was a difference between the color monitors used on the Macintosh and that used by the IIGS, so an adapter for a Mac monitor might not work. I've never seen a Mac monitor hooked up to a IIGS, but I have seen a IIGS hooked up to a TV via a VCR & the video out port.

I apologize for being so vague, but I initially heard this around the time the LC came out, and I think it was also mentioned in a discussion around a decade ago on comp.sys.apple2.