Mac IIcx monitor options

[cesare]

I've picked up a Mac IIcx which is now getting as far as a boot beep - there was some corrosion on the board, but nothing too terrible, and i've given it a decent clean, replaced the SMD capacitors, and have replaced some cracked RIFAs in the PSU.

So next up, i'm trying to get video out from the machine. I used to own a IIcx when they were originally released, and i'm a bit of a hoarder, so i've got my old graphics card from then (Mac II video card, with the extra ram populated), and looking at the output on a scope, i'm seeing what would be a passible impersonation of a video output feed (only RGB, sync on green maybe?), but i'm aware that it runs at an unusual refresh rate. I'm also guessing that there's no way for this old card to produce anything other than the 640*480 at 66Hz or whatever it was?

So what's the right way forward - are there any VGA conversion boards which will feed a modern monitor, or maybe a better multisync supporting monitor, or of course if anyone has a spare original apple trinitron CRT knocking about they want to get rid of, that would help

 

[Patrick]

There were a bunch of converter mac to vga box's. most with little dip switches so you can configure it correctly.
They dont' always work with all monitors.

https://www.bigmessowires.com/mac-sync-inator/

is a new one.... which should be available to be sold soon. (its currently sold out)

He also sales a bunch of other stuff that might be useful. like a floppy emulator. and usb <-> adb device.. (i use it to plug a ADB keyboard to my work macbook) but it can work the other way around also.

 

[GiGaBiTe]

If you get one of those DB-15 to DE-15 adapters, make sure it has jumpers and isn't just a straight pass through, because that's how the video card knows what resolutions the monitor is capable of. Straight pass-thru adapters will generally just run at 640x480@67 Hz.

As for what monitor to use, I find that older square Dell LCD monitors will handle most of the weird Apple resolutions and refresh rates. I have an old square Dell 15" LCD monitor that will sync 640x480, 832x624 and the oddball 1152x870, though not perfectly. The 624p and 870p resolutions have moire patterns and are squished slightly. The higher end Dell monitors that allow you to change the pixel scaling and manually set the H/V widths will give a better image.

Once you start getting into the widescreen era, monitors quickly started dropping support for those oddball resolutions and refresh rates, though there were a few odd ones out there that did. I have a 22" LG panel from 2012ish that will sync most of the modes except for I think 1152x870.

I don't have a Mac that will output 512x384 (LC/LC II) or a IIe card (560x384), but I don't think those LCD panels will sync to a size that low. Also pretty sure the oddball 640x870 mode for the Apple Portrait Display won't work either.

 

[cesare]

Thanks for the info, i'm sort of remembering using such adapters with a PowerPC 7500, which was the machine I got after the IIcx. I ran the IIcx with a Radius Pivot display as well (grey scale), and it was used for Emagic Logic for midi sequencing and some music notation. I've actually found the old Logic install floppies, but I don't have an ADB dongle for it, I think that was handed in when they moved to a USB dongle for later versions. It would be awesome to get the old system running, but i'll start with confirming that the display card works

I do have a few older monitors here, i'll try an adapter and some of these first I guess to see if I have any luck.

 

[cesare]

Progress.

I dug through random cable boxes and found a DB15 to VGA adapter, and found a VGA display which is happy with the signal, so success, I can see what's going on, and the video card does indeed work. No HD installed, so that's as far as that got.

However, I came across a period correct CRT on sale locally, along with an old LC, for sensible money, so i've not got a 12 inch colour CRT to go with the machine. They two look excellent together. It's at this point that I discover that the video card I have will *only* work with the 13 inch high res trinitron screen, and the 12 inch display uses a lower resolution.

The LC has somewhat leaky capacitors and doesn't start up, so i'll have a go at repairing that. It's got some unusual SMD capacitors on board, so i've not got suitable replacements to hand, so i'll order some in. I've removed the caps and given it a good clean, and a visual inspection looks like it's got away without obvious damage, so fingers crossed this is one more saved from landfill.

I tried the HD from the LC in the IIcx, and this works, and so i've managed to bring up system 7 on the IIcx using the VGA monitor, - success!

So next steps - still be on the lookout for the trinitron 13 inch hi-res screen - you never know, one might appear. Meanwhile, try and track down a Nubus video card which will support the lower res screen I now have, and also fix up the LC so that it's working as well.

I'll also need to get a second HD running for the second machine, assuming this can be got running. Not sure I understand the HD requirements yet, i've got some older but larger SCSI drives here, which may be able to be called into service.

 

[fred1212]

Bluescsi maybe