My first CP/M Computer

A few weeks ago an intriguing post popped up on Craigslist.  It was for a CP/M computer that someone here in the Minneapolis / St. Paul Metro area had built up from the board level in 1983.  I believe the builder re-used a piece of old test equipment as the Chassis, and perhaps the power supply that was in the Chassis as well, but the computer itself is a Megatel Quark 100 computer.  This was a Canadian firm.  The computer is a Z-80 based system with 128K of RAM (64K available to CP/M), and two Teac 360K floppy drives.  (I'm still not sure what the formatted capacity of the drives is, since I'm a CP/M newbie.)

At some point the previous owner had recycled the Monitor.  I don't have an MDA / Hercules compatible monitor in my collection, so I ordered and waited for an MCA2VGA to arrive from TexElec.

Once I got the video adapter and a 9 pin male to 9 pin male straight cable, I was able to fire the machine up and test it for the first time, it boots and runs well...

There appears to be an issue with the Horizontal Sync timing on the MCA2VGA adapter, as the last few columns of text on the right hand side are cropped.  Also the video is compressed vertically too about 1/2 of the height of the screen, so I'm not sure what's going on there.  The manuals for the Quark mention specific horizontal refresh timing, but I'll have to dig in on what the timings are supposed to be for MDA / Hercules in order to understand why this isn't working on MCE2VGA.  I'm also on the lookout for a period correct monitor.

The next challenge was the Key Tronic foam and foil keyboard.  Several of the keys were not working...

I've restored a similar keyboard before on my Compaq Portable from the same year, and once again TexElec came to the rescue with their Foam and Foil replacement pads.  Waiting for the pads to come in gave me the opportunity to take the board completely apart and clean the housing and keycaps.  After replacing the pads and re-assembly, the board is working like new, although there's some wear and tear...

I'm quite happy with how this turned out given that the keyboard is over 35 years old!

The next challenge was that the builder of this system mentioned to me that the BIOS is on a Floppy Disk.  The computer won't boot at all without the customized, appropriate BIOS for the peripherals that are wired to this specific build of the Quark.  This left me with a nagging fear that as the floppy disks fail, I'd loose the use of this classic computer.  I'll write a separate bLog article about my new SuperCard Pro Disk Imaging setup, but too make a long story short, I was able to image and restore Bootable CP/M disks for this machine, and capture and archive all the disks that came with this system, so that is a relief.

That wraps up the story so far for my first CP/M computer.  It's working well enough that I can dive in and start learning about CP/M, the precursor operating system to DOS.  There's alot of good information online, and I'm planning to start with "The CP/M Handbook with MP/M" by Rodney Zaks.

On my To-Do list for this computer:

Find an appropriate monitor that can be adjusted to show all the text, or determine why MCE2VGA isn't displaying the image correctly.

Find a Go-Tek equivalent for 360K 5 1/4" drives so that I can replace one of the floppy drives with a solid state drive.

Please let me know if you have any suggestions for me about this computer, or any questions, Thanks!