Looking for info on National Semiconductor RAM board (VAX 11/730)

Mark J. Blair nf6x at nf6x.net
Sat Jun 20 10:11:41 CDT 2015

> On Jun 20, 2015, at 07:40, tony duell <ard at p850ug1.demon.co.uk> wrote:
> Does anyone recognise this board?

I don't recognize that board, but I thought I'd point out the non-DEC memory in my 730. It uses Camintonn CMX-750 memory boards, and I have a CMX-750/730 installation manual that I can scan. I plan to scan it for Bitsavers and Archive.org anyway, but it can jump higher in the queue if anybody has an acute need for it. I pulled one board out of my machine to look at it, and it does not appear to have that oddball extra RAM chip. It has a red paddle type toggle switch and an LED.

> A related point, I am thinking of removing the TSU05 from my 11/730 and putting an expansion 
> box in place of the tape drive in the rack. In which case I can install this memory board. Is 5MBytes
> (the maximum an 11/730 can take) worth having over 4MBytes?

In my system, the M9302 bus terminator (dual) and M7454 TU80K (quad) are in the same row. Would this imply that I could replace the M9302 with a BC11 cable to add an expansion cabinet without losing any of the functions already installed in the CPU cabinet? And if so, maybe Tony's system could also grow an expansion cabinet without losing the TSU05 card?

Mark J. Blair, NF6X <nf6x at nf6x.net>

More information about the cctalk mailing list