ebay: Are these PDP-8 boards?

[Ethan Dicks]

On Sat, Dec 01, 2007 at 10:46:18AM -0700, Richard wrote:
> Item # 320190208819
> 
> They look too small to be Qbus and the module numbers are all 3
> digits, whereas all the Qbus and UNIBUS module board numbers I've seen
> had 4 digits.

You have probably only seen later stuff - have a look at a pre-1978
backplane-sized peripheral - the M105 is a Unibus Address Selector (from
memory - it's at least part of older, multi-board, Unibus peripherals).
 
These cards look like pretty much ordinary FLIP-CHIP modules, which
were used to make a variety of CPUs and periperals in the 1960s and
1970s.  I don't recall any Qbus stuff made up of these, but there was
plenty of Unibus (PDP-11) and pre-OMNIBUS (PDP-8) stuff, chock full
of these and similar cards.

> This looks like a good deal for someone looking for spare flip-chip
> modules or maybe someone who wants to reverse engineer this pile of
> flip-chip modules and wire-wrapped backplane to figure out what it
> used to do :-)

The seller shows a photo of the nameplate which *says* what it used
to do - it's an RS08 backplane.  The RF08/RS08 is a fixed-head disk
for the PDP-8.  The RF08 was the master, the RS08(s) was/were the
slave disks.  Obviously, this doesn't include a drive mechanism,
nor the smart part of the RF08, but it's still an interesting piece.

-ethan

-- 
Ethan Dicks, A-333-S     Current South Pole Weather at  1-Dec-2007 at 17:50 Z
South Pole Station
PSC 468 Box 400       Temp  -27.2 F (-32.9 C)   Windchill   -43.1 F (-41.7 C)
APO AP 96598          Wind   4.6 kts Grid 124   Barometer 678.2 mb (10696 ft)

Ethan.Dicks at usap.gov            http://penguincentral.com/penguincentral.html