Interesting, I was never aware that the 11/03 and 23 had different boxen
than the 11/23plus, though I knew the power supplies were different.
Speaking to my local DEC salvage dealer, he told me he used to get whole
11/780s just for the power supplies in the front end 11/03s. However,
judging from the number of 23plus systems that were sold (and have recently
hit, if not flooded, the used market)I'd say it should be fairly easy to
find a cheap H7861 supply.
-----Original Message-----
From: cctalk-bounces at
classiccmp.org [mailto:cctalk-bounces at
classiccmp.org]
On Behalf Of Pete Turnbull
Sent: Wednesday, November 23, 2005 11:52 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Mouse Pissed! Need power supply help
On Nov 23 2005, 10:51, Charles wrote:
I've found the reason why my PDP-11 power
supply (H7861) is not
putting out POK and DCOK signals.
[ ... ]
Unfortunately the H780 schematic does not match
closely (they use
74123's while this one uses 555's, for example) so it'll be hard
to figure out the missing or unreadable parts anyway!
The H7861 is a reworked version of the H786 design, which is fairly
different from the H780. The H786 is used in the BA11-N box commonly
used for PDP-11/03 and 11/23 systems, and the H7861 is used in the
BA11-S box commonly used for 11/23plus and 11/73S systems, so you
should be able to find the schemeatics amongst the BA11-{N,S} drawings.
--
Pete Peter Turnbull
Network Manager
University of York