New Donations at the RICM

[m_thompson]

Alan Sieving, owner of Quickware, just donated two PDP-11/44 and two PDP-11/84 systems, a bunch of disks, disk drives, and 1/2' tapes to the RICM. Unfortunately Alan is still supporting Quickware customers, so we didn't get his QED-95 upgraded PDP-11/70 or any other Quickware CPUs. :-(

One of the PDP-11/84 chassis is as expected with the power supply to the right of the 12-slot backplane. The other chassis says PDP-11/84 on the front, but has the power supply in the back, like an 11/44. It has similar backplane to the other 11/84, but does not have an M7677 MDM board, and has a lot more Unibus slots. It looks similar to an 11/94, but that would have an MDM board. It has seven DZ-11 boards in it. I can't imagine what you would do with 56 serial ports!

I need to investigate this second 11/84 some more, and would appreciate any help identifying what it is.

 

[tradde]

My 11/84 has the power supply on the back as in the 2nd picture. 56 serial ports? That's quite a few. I have a serial port board in mine, but do not have the rear connector panel for it. Never heard of an M7677 MDM board. I have some manuals for mine but it covers several different types of 11/84s.

 

[Hunta]

Never heard of an M7677 MDM board

 

[tradde]

Ok, what does it do? Searching online I did not find much for describing what it does. Thank you.

 

[Hunta]

www.bitsavers.org/pdf/dec/pdp11/1184/EK-1184A-MG-001_1184maint_Nov86.pdf, pages 2-12 - 2.14

 

[tradde]

Thank you.

 

[m_thompson]

I have some manuals for mine but it covers several different types of 11/84s.

There is very little documentation for the newer 11/84 chassis on Bitsavers. There is only one manual there for the 11/94 which looks like it shares the newer 11/84 chassis. Do you have scans of the 11/84 manuals that are not on Bitsavers?

 

[tradde]

I have a slightly newer User and Maint guide @ -002. And the same technical manual as on bitsavers. From a quick scan of the Maint manual I see no reference to an MDM module in it. This manual is dated Jan 1988.

 

[m_thompson]

It looks like the "E" revision of the 11/84 uses the chassis with the power supply in the back. The BA11-A Rev E docs on Bitsavers has the H7204 power supply schematic, the one that is in the back of the chassis.

The next time I am in the RICM warehouse I will see if there is a MDM slot in the 11/84-E chassis, and take a picture of the bottom of the backplane. I suspect that the backplane is different than the one in the earlier 11/84 chassis, and also different from what is shown in the 11/94 docs.

 

[m_thompson]

I spend some more time with the recent donation today. The PDP-11/84 with the power supply on the side is an 11/84-AA. The 11/84 with the power supply in the back is an 11/84-EX-A01. The chassis for the 11/84-E really looks like an 11/44 chassis.

The attached image shows the two 11/44s at the left, one has dual TU58s and battery backup. The next to the right is the 11/84-E, then two cabinets with Cipher M990 CacheTape drives in the top and 2x SMD disks in the bottom. Then the 11/84-E with an RA81 in the bottom, an RM03, and a CDC 9762 disk.

Not shown are an empty 11/34 chassis and an RL02 drive.

We also got a large pile of RL01, RL02, RM03, RM05, and CDC 9766 disk packs. There are a few DEC software distribution 1/2" mag tapes.