archive.worldofdragon.org

looking at even older issues, I have found this one related to RAM upgrade project for the Dragon ... - 1986 03 - Issue 19 article upgrading the Dragon by Bob Hall cheers! Good find. That speaks about upgrading the 64 to 256k. If you find any discussion concerning upgrading to 128k, please let me k...

The fourth segment is in the first issue of 1988.

I have had a quick read of them. There is a fourth and final article in the next issue. I was hoping to find some information about the changes Bob made to the actual motherboard(s) but all the discussion seems to concentrate on how the MMU works. Nevertheless, really quite fascinating. I wonder wha...

More fascinating information on this now apparent rare gem of a machine. Thank you.

So...the question is, what is Bob's secret "switch" to make our machines work again?!

They were 4564. Yes, it was a 128k upgrade with MMU.

Mr Hall sounds like a fascinating person. What information is known about him?

This is how it looked originally:

I posted this earlier. If you need any more, please let me know.

Sure. It is 005837. When I received it, this board was inside, it was not connected: IMG_20260312_092857.jpg IMG_20260312_092922.jpg There were RAM ICs soldered on each motherboard RAM IC and there were some pins soldered on to various points of the RAM and logic ICs. Presumably wires from the board...