Apologies - Only just realised it was a closed group anyway so you can't see it without joining the actual group - sometimes public groups you can see without joining FB...
Anyway it links to this site:
https://www.hb9afo.ch if you go to Articles and look down to 1982 there is Micro-Von in Megahertz magazine.
On the group George Rudolf Mezzomo has created a free to use for non profit modern SBC adaption. here is a photo - I hope to get a small number made if anyone is interested in an at cost one.
The PDF is one I found somewhere for an alternate I cannot find the source.
ins8073_board-schematic-1982.pdf