23 Nov
2011
23 Nov
'11
3:15 p.m.
Guys,
The original part would be the ideal -- and that's what I'm hoping for.
But reality has already begun seeping in!
Yes, I'm afraid I've already checked in with Crisis, and I'm in contact
with the person who bought out their 21xx stock. It's not looking
promising. Though a weekend trawl of their parts bin may yield
something.
Tony's right, of course. The next best thing is to work up a replacement
board. I've already started doing that. I've asked around for
photographs from people I know have the 'B' model. Through a combination
of photos, schematics published in the old maintenance manual, and
Brent's schematics for the C, I should be able to get a working
replacement fabricated. An original is still preferred of course, and
if anyone out there has one available, I'd love to hear from them.
The 2160/61 is a thought. And I do have access to one. I believe the
design is substantially different though. The part numbers certainly
are. I shall have to peel the covers back on it when I'm out at
Bletchley this weekend and compare it's bits with the maintenance manual
schematic.
It's always possible a board with turn up buried in the uncatalogued
collection somewhere. But I'm not optimistic. Anyone familiar with the
TNMOC collection will appreciate how challenging it can be to do an
exhaustive search at the moment. I've already done a fairly broad hunt.
I'm working on sorting/cataloguing all the unmanaged HP gear as part of
the process, but most of what I've discovered so far is from the next
generation of systems > 1970. The IO cards may be usable, but the power
supply design changes pretty substantially.
On Wed, 2011-11-23 at 14:33 -0800, Brent Hilpert wrote:
On 2011 Nov 23, at 6:53 AM, Colin Eby wrote:
-- Colin
Logic regulator is missing from both systems,
yes. Memory regulator
is missing from the C. One arithmetic logic card is missing from
one system- but they should be pretty interchangeable. So I have a
full set for one running system.
With the logic regulator card, the B would be functionally
complete. Thanks for the schematic. I've started transporting the
manual scans into a PCB design tool should it become necessary to
get a new board fabricated. I'd much prefer to find an original
though!
In discussions about the 2116 a few years ago, a former list member
referred Crisis Computer as a potential source for parts:
http://www.crisis.com/
The web site lists stuff as far back as the 1000 series (2100 follow-
ons). Slim chance perhaps, but might be worth asking.
What about the 2160 and 2161 PSUs? It's conceivable they could use
the same board(s).