22 Nov
2004
22 Nov
'04
10:35 a.m.
Message: 2
Date: Wed, 17 Nov 2004 00:25:22 +0000 (GMT)
From: ard(a)p850ug1.demon.co.uk (Tony Duell)
Subject: Re: KM11 maintenance module
To: cctalk(a)classiccmp.org
Message-ID: <m1CUDdV-000JEQC@p850ug1>
Content-Type: text/plain
The KM11 is also present in the 11/05 (11/10) printset I have.
I would also expect this to appear in the 11/35 (11/40) printset too.
The interesting thing is that in every different place the KM11 is used, a
different overlay will redefine the meaning of the lamps, so in fact you
will need this picture of the overlays too!
Frank
See if you can find the cpu manuals for an 11/70.
There are some
documentation on the KM11 in those, I seem to remember.
The original KM11 (I was given a pair _after_ making my homebrew
version..) consists of 2 boards -- IIRC W130 and W131. One contains the
switches and lamps, the other the driver transistors, etc. The latter
goes into the backplane slot and had an edge connector on the end to
connec to the former.
I think I got the schematics in the RK11-C printset, certainly it's
either there or in the 11/45 prints.
-tony
23 Nov
23 Nov
11:20 a.m.
Frank Arnold wrote:
The KM11 is also present in the 11/05 (11/10) printset
I have.
I would also expect this to appear in the 11/35 (11/40) printset too.
I found a copy of the schematic in the RK11-C printset. Mr. Duell's
description does an excellent job of updating it. What is the equivalent
of the DEC3009 transistor?
There was a discussion a while back about an equivalence chart for the
DEC transistors. I can't seem to find the reference anymore. Not that I
plan to make one from discretes, but it would be pretty easy to wire
since it is such a repeatable pattern.
The interesting thing is that in every different place
the KM11 is used, a
different overlay will redefine the meaning of the lamps, so in fact you
will need this picture of the overlays too!
True, but if you have the manual that describes how to use the KM11, you
usually have an image of the overlay.
It looks like the lamp board is a dual width, single height. It should
not be difficult to take the overlay images from the manuals and
photocopy them onto overhead transparencies.
Frank
-chuck
3:14 p.m.
I found a copy of the schematic in the RK11-C
printset. Mr. Duell's
description does an excellent job of updating it. What is the equivalent
of the DEC3009 transistor?
I think just about any NPN transistor that would handle the lamp current
would worl.
A word of warning (discovered the hard way!). Some DEC machines put 1k
(or so) resistors in series with the input signals to the KM11. If you
use TTL buffers to drive the lamps (I tried 7406s), it won't work
properly -- they take too much input current. Also, some machines fed the
lamp off an unsmoothed supply, hence the capacitor between the '8V' line
and ground.
True, but if you have the manual that describes how to
use the KM11, you
usually have an image of the overlay.
From what I remember the PDP11/45 prints didn't
include the overlay
patterns ;-(. I did trace out all the signals, I can provide a
pattern if
you need it.
It looks like the lamp board is a dual width, single height. It should
Both the boards were single height, extended length.
-tony
7334
days inactive
7335
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