If you are concerned about hex height boards or mos, you can always use a BA11-KE expansion box.
On Mon, Mar 27, 2017 at 6:04 PM, Ethan Dicks via cctalk < cctalk@classiccmp.org> wrote: > On Mon, Mar 27, 2017 at 12:20 PM, Al Kossow via cctalk > <cctalk@classiccmp.org> wrote: > > On 3/27/17 7:37 AM, Systems Glitch via cctalk wrote: > >>> I don't know of MOS memory appearing in 11/20s as built by DEC, but > there's no reason against it. > > > > There were 3rd party cards, Monolithic Systems, for example. > > The problem with the 11/20 is that hex wide cards don't fit, the fans > overlap the unibus jumper area. > > If you ever see hex-wide cards with a big notch in one end, they were > designed to work in the 11/15 11/20 > > Exactly. There are plenty of hex-height cards with MOS memory for > Unibus (I have several for the 11/04 and/or 11/34 of a suitable size) > but they would fit in an external BA11-K or BA11-L w/DD11-DK, not the > CPU's BA11 because of the fans. That's why I was wondering if DEC > ever made quad-height MOS modules for Unibus or if all DEC-supplied > 11/20s and 11/15s had core and only core. > > -ethan >
