On Apr 19, 2024, at 9:42 AM, Sentrytv via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
From: Sentrytv <sentrytv@yahoo.com> Subject: Re: [vcf-midatlantic] Apple IIgs Black Screen Date: April 19, 2024 at 9:42:51 AM EDT To: vcf-midatlantic <vcf-midatlantic@lists.vcfed.org>
The Apple2 GS uses a specific monitor And is not compatible with a Mac monitor!
I can’t remember if the signals are digital or analog but I assume they are digital and it might be considered RGBI 15 kHz I’M SURE THERE ARE MORE PEOPLE HERE WHO HAVE THESE EXACT SPECS Mike
It's a 15 KHz horizontal refresh rate monitor, same as TVs and arcade monitors. Fun fact: you can hook the IIgs' monitor up to a lot of arcade boards as a display, though sometimes you might need to change from the default sync polarity. I used one to test my Defender boardsets back when I still had my IIgs, and it worked like a charm. There are also some Dell LCD monitors that support unusual features for LCDs (sync-on-green, interlaced video) though I'm not sure if they'd do 15 KHz. I no longer have a IIgs to test with, but I have heard very good things about the P1914's compatibility with a lot of things, and they're definitely very cheap on eBay these days, and worth keeping around for a lot of vintage things (a lot of old Macs also do sync-on-green, some of them like the IIci *only* do it, and a monitor that handles it correctly is essential if you don't want everything looking very green). If you're using a VGA converter, be cautious; the monitor sense signal lines function a little differently than they do on the standard Macintosh DA-15 video connector, and cheap ones can often short something to ground which prevents startup and may not be great for the machine in the long term. If you happen upon a Griffin MacPnP adapter, they're really the best of the bunch (and if you don't have one, let me know, I bought about a dozen of them a while back when someone was selling bucketsful on eBay for $4 each). - Dave