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Just got back from the Vintage Computer Festival East 2016 in New Jersey Reminded me that I have to get some more info out to the public on this video mod that i used about 30 years ago. Have to drag the machine out of storage and document the actual traces to cut. Most were selected so you can just...

Please do post
I'd love to se how others have don it

yes, I always thought it was pretty neat, but in the day, no real internet, forums, etc, to share. The original display on a green monochrome monitor was really nice. The photos shown are using a modern flat screen LCD tv using the yellow video in. Interesting you get Square pixels. I tend to get a ...

The crystal frequency I mentioned above is wrong. I wrote the discription from memory and forgot to correct the crystal frequency before submitting. The cryttal is 3.932160 which when divided through a 16 stage divider comes out at exactly 60 Hz the correct frequency for Vertical Sync in America. Be...

When I get a chance I will show photos of where to cut the traces and how to add the wires needed.
I picked up most of the signals from through hole connections by soldering square wire wrap posts in the plated thru holes
and using wire wrap to route the signals.

Photos and details to follow...

Here is the long story of my Video Upgrade for the C1P challenger board. OSI C1P Simple Video Upgrade. This "fix" requires cutting 4 traces and adding one 74LS00 chip. It can double the characters per line by "stealing" the ram from the previous line. Thus giving half the lines per screen but double...

Worked on the board again tonight and got it working. Looks like I had a bad RAM chip also. My main goal was to get the video to clear (shows the processor is running some code) and give the DCWM prompt and then respond to the "M" input showing it can read the keyboard. I took out all the BASIC ROM ...

Just got my C1P or superboard II running after 35 years in storage. It actually came up running ok but then died. I am using an LCD monitor/TV using the video in (yellow, white, red RCA jacks). use the yellow only. Don't try it with component video using blue green etc RCA Jacks. I found the best ga...

So, at this point, I have just the monitor ROM and 1 line of RAM plugged in. No BASIC roms System seems to consistently come up with video garbage on power up (this was always normal). Reset clears the screen and put out the prompt, but no response to any keys. If I keep hitting the reset it doesn't...

thanks for the info on adding photos. I will have some in the future... My machine which was running perfectly, suddenly went south. I thought I traced it to the 74ls138 chip which decodes the address for the video and keyboard. I verified this by taking out the CPU and playing with address lines 13...