The above is the board that I got for my Nascom-1. The photo below is one that I found elsewhere. I don’t think I ever saw any more blue ones.

This board was essential for all NASCOM-1 owners who wanted to expand their systems. I doubt that the NASCOM-1 was ever intended to become as popular as it did. The designer(s) didn’t include sufficient on-board buffering to drive a bus system. Hence the introduction of this board. The three grey ribbon cables terminated in an edge connector to fit the NASCOM-1. The card was then plugged into the first slot of the motherboard and so connected the necessary signals.

Buffer board circuit diagram

This board also produced a “clean” reset pulse so that the system monitor could be restarted without losing data and programs currently in memory.

A further circuit was a replacement clock pulse generator (the main system timing signal) which allowed use of some of the more advanced ICs.

The Nascom 2 was already expandable, and connected directly onto the NASBUS, so this board wasn’t needed.

Nascom Pages