6 Oct
1999
6 Oct
'99
10:39 a.m.
Well, the pdp8/e power sord was cut off, but there is a 2 foot long hunk of
wire. I suppose I'll just wire up a power connector, and they use a good
quality extension cable (someday). No rush on that...
The core memory planes were removed, of course. Looks like there were at
least 3 sets of core in this at one time. The foam along the side of the
case has pretty much vaporized and is all over the bus connectors. Whats
the general consensus (yeah right, on THIS mailing list i was a consensus...)
about removing versis replacing that foam?
And one front panel switch is gone, and another is present but broken. The
rest at least appear to click up/down properly.
Boards that were in my PDP8/e when I recieved it
===============================================
M8330
M837
M8655
M8360
M8350
VG DS (dont know the number)
M8655
M840
M849
M8310 Loose
M8300 Loose
G111 Loose. 2 of these
G233 Loose. 3 of these (too bad they didnt leave the core planes)
M935 2 of these, to connect the second bus
VG DS 505
VG DS 102
VG DS 101
VG DS 504
M8320
M847 YH Bootstrap Loader (32 words implemented via an array of diodes)
6 Oct
6 Oct
11:58 a.m.
Well, the pdp8/e power sord was cut off, but there is a
2 foot long hunk of
wire. I suppose I'll just wire up a power connector, and they use a good
quality extension cable (someday). No rush on that...
That's pretty easy to replace, make sure you use a heavy gauge.
The core memory planes were removed, of course. Looks
like there were at
least 3 sets of core in this at one time. The foam along the side of the
case has pretty much vaporized and is all over the bus connectors. Whats
the general consensus (yeah right, on THIS mailing list i was a consensus...)
about removing versis replacing that foam?
The foam helps keep the cards from knocking against each other. Thus it is
good to replace, it is also a good idea to remove the old foam and vaccum
out the back plane! Many times plugging a card into a slot that has foam
wedged in it gives bad results.
And one front panel switch is gone, and another is
present but broken. The
rest at least appear to click up/down properly.
I've got a spare switches in the darker orange but may not have one in the
lighter yellow. Let me know if you'd like me to send them out to you.
Tell us, did you get the "long" box or the "short" box? (the long box
has
two back planes in it connected by a row of jumpers.)
Boards that were in my PDP8/e when I recieved it
===============================================
This one is Timing/Control
M8330
These two go next to it.
M8310 Loose
M8300 Loose
The sequence is M8330 M8310 M8300 (and if you get an M8340 and M8341 they
will go between the 8330 and the 8310) Normally they are connected across
the top with top connectors. These look like short two plug back planes. If
you don't have these see if you can go back and root around for them. In
the 8/e/f/m you need at least 6 (4 for memory, 2 for the CPU)
This one:
M837
Gives you extended memory control, up to 8 "pages" for a total of 32K of
core. It isn't required to operate the machine but without it you are
limited to 4K of core.
This one:
M8655
Is a serial port. (and the nicer one too!) You can run this one at RS-232
levels right into your PC at 4800 or 9600 baud. See comments on Doug Jones
and Aaron Nabil's sites for modifications and building cables.
These two:
M8360
M8350
Make up a positive bus interface and a DMA (data break) card.
VG DS (dont know the number)
Another serial port:
M8655
This one I'm drooling over:
M840
This is the high speed paper tape interface. It connects to the PC04
reader/punch.
This one
M849
is an RF shield it sits between the core
stacks and the CPU to protect them
from stray magnetic fields that might perturb their
bits.
This is:
G111 Loose. 2 of these
G233 Loose. 3 of these (too bad they didnt leave the core planes)
Parts for 2.5 8K
core stacks. You need the H212 core mats to complete the
picture.
these indicate you got the "long" box yes?
M935 2 of these, to connect the second bus
[snip]
These are the bus loads and go in the last slot.
M8320
pretty clear what this does. Pretty cool though.
M847 YH Bootstrap Loader (32 words implemented via an
array of diodes)
All in all a pretty good catch. While it may be hard to get core for this
thing you can find MOS memory systems at various places. The thing to worry
about will be the top connectors. If you don't have them you can make them
but it isn't fun. Some folks on the pdp8-lovers list might have spares.
Other questions:
What was the date of manufacture? (on the back by PSU)
Is the front panel lamps or LEDs?
--Chuck
12:13 p.m.
On Wed, 06 Oct 1999, Chuck McManis wrote:
Tell us, did you get the "long" box or the
"short" box? (the long box has
two back planes in it connected by a row of jumpers.)
[...]
Is the front panel lamps or LEDs?
If it's a short box, or has LEDs instead of incandescent lamps, that'd make it
an 8/f or an 8/m according to the '73 Small Computer Handbook.
-Dave McGuire
12:46 p.m.
M837
Gives you extended memory control, up to 8 "pages" for a total of 32K of
core. It isn't required to operate the machine but without it you are
limited to 4K of core.
2:36 p.m.
And one front panel switch is gone, and another is
present but broken. The
rest at least appear to click up/down properly.
I've got a spare switches in the darker orange but may not have one in the
lighter yellow. Let me know if you'd like me to send them out to you.
Tell us, did you get the "long" box or the "short" box? (the long box
has
two back planes in it connected by a row of jumpers.)
Long box, of course ;)
This one:
And I just noticed that I actually have one usable cable, though it is very
short. It runs from one of the serial boards, to just barely out side the
back of the case, and it is labeled VT55. A white plastic connector, single
line of connectors, and if i recall correctly, 6 wires connected. Some
sort of current loop connector i'm assuming.
M8655
Is a serial port. (and the nicer one too!) You can run this one at RS-232
levels right into your PC at 4800 or 9600 baud. See comments on Doug Jones
and Aaron Nabil's sites for modifications and building cables.
These two:
Which is nice. But what does this get me in the real world?
M8360
M8350
Make up a positive bus interface and a DMA (data break) card.
This one I'm drooling over:
Yep. Unfortunately I dont have any peripherals. Except the one RL01, and
apparently I dont have an interface board for that.
M840
This is the high speed paper tape interface. It connects to the PC04
reader/punch.
This is:
I've always wanted a PDP8/e. Always. Which is why I already had in my
possession 2 complete 3 board sets of core memory, 8K per set, for the
PDP8/e! And I bought another 8K plane on ebay this summer. these things
tend to attract one another...
G111 Loose. 2 of these
G233 Loose. 3 of these (too bad they didnt leave the core planes)
Parts for 2.5
8K core stacks. You need the H212 core mats to complete the
picture.
All in all a pretty good catch. While it may be hard to get core for this
thing you can find MOS memory systems at various places. The thing to worry
about will be the top connectors. If you don't have them you can make them
but it isn't fun. Some folks on the pdp8-lovers list might have spares.
I think I have enough. Not if I want to get a third set of core memory
installed, but its a long shot that the third set will work anyways. At
the very least the boards have to be tuned to work together, or some
such magic incantation uttered.
Other questions:
What was the date of manufacture? (on the back by PSU)
Is the front panel lamps or LEDs?
Its standard pdp8/e lights as far as I know. Manufacture date is 1976.
If I read the codes correctly, its the 24th week of 76, and then some
other paper sticker on the top case, applied with scotch tape and only
partially still existing, mentions october 11, 1976, which I assume is
when some company then added their boards to make a specialized product.
One strange thing... The front panel doesnt say Maynard, Massachusettes, as
I expected... it says something like Galway, Ireland. Oh my GOD, its
the RARE Galway version! I can sell this on ebay and have more money
than Bill Gates! er, aHem.. I'm much calmer now...
Ok, so what do I need to obtain from here.. looks like I have the basics
of a PDP8/e system with serial ports. High speed paper tape reader interface,
but no paper tape reader... What would make this a minimal usable system?
Just adding a TTY33, and getting someone to copy a few paper tapes, perhaps?
If the core memory doesnt work out, is the MOS memory actually affordable?
Anyone willing to tell me some PDP parts suppliers that may have some
interface boards, like whatever I need to hook up that RL01 (what exactly
is a RL01 anyways). Maybe I should be looking to add floppy drives, etc.
OR, are people using IBM's as a terminal, and running some program that
pretends to be an attached paper tape reader/punch unit? That might do
for starters, though its not anywhere near as satisfying.
-Lawrence LeMay
3:15 p.m.
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6:31 p.m.
Yep. Unfortunately I dont have any peripherals.
Except the one RL01, and
apparently I dont have an interface board for that.
The RL8 is a hex card, and won't fit in the 8/e box. I have one in my
8/a. I bet there _was_ one behind one of the 8/a panels that you couldn't
remove.
3:21 p.m.
New subject: Next steps (was Re: pdp 8/e)
The two bad switches are yellow ones. The switch
mechanism is there, its
the paddle that is broken in one case, missing in the other. Though if I
cant get yellow someplace, then any color is better than a non-operational
computer...
Well, let me know. I've got a toasted 8/M front panel that I've used to
restore an 8/M and an 8/F. (one of the colors matches)
And I just noticed that I actually have one usable
[M8655] cable, though
it is very
short. It runs from one of the serial boards, to just
barely out side the
back of the case, and it is labeled VT55. A white plastic connector, single
line of connectors, and if i recall correctly, 6 wires connected. Some
sort of current loop connector i'm assuming.
Yup, that would be the DEC "standard" three loop current loop interface.
(Tx loop, Rx loop, reader-run loop). You can get a compatible BERG
connector for the 8655 from Digi-key and build your own RS-232 cable. Check
out the schematics on Dave Gesswins(sp?) page.
Make up a
positive bus interface and a DMA (data break) card.
Which is nice. But what does
this get me in the real world? Yep. Unfortunately I dont have any peripherals. Except
the one RL01, and
apparently I dont have an interface board for that.
I don't believe DEC made a Quad RL controller. I've only seen the M8433
which is a hex wide RL controller that plugs into the PDP-8/a. But you also
said you have the Omnibus expansion stuff, which means that if you get a
PDP-8/a backplane you can jumper over to it and install the RL controller
there...
I've always wanted a PDP8/e. Always. Which is why I
already had in my
possession 2 complete 3 board sets of core memory, 8K per set, for the
PDP8/e! And I bought another 8K plane on ebay this summer. these things
tend to attract one another...
Bravo!
I think I have enough [top connectors]. Not if I want
to get a third set
of core memory
installed, but its a long shot that the third set will work anyways. At
the very least the boards have to be tuned to work together, or some
such magic incantation uttered.
Yes, I have just such a stack and its a bit daunting at the moment.
Its standard pdp8/e lights as far as I know.
Manufacture date is 1976.
Hmm, look at the front panel from the front, then look over the top and on
what is the left hand side, see if it has one power line hooked up or two.
If it is only one, there may be LEDs. I thought they didn't make any lamp
panels after '74 but I'd love to be proven wrong.
One strange thing... The front panel doesnt say
Maynard, Massachusettes, as
I expected... it says something like Galway, Ireland. Oh my GOD, its
the RARE Galway version! I can sell this on ebay and have more money
than Bill Gates! er, aHem.. I'm much calmer now...
Now _that_ is fascinating. If you get a chance read the part number of the
panel off the back and post it. Also be _sure_ the power supply is looking
for 110V and not 220V!!
Ok, so what do I need to obtain from here.. looks like
I have the basics
of a PDP8/e system with serial ports. High speed paper tape reader interface,
but no paper tape reader... What would make this a minimal usable system?
Just adding a TTY33, and getting someone to copy a few paper tapes, perhaps?
If the core memory doesnt work out, is the MOS memory actually affordable?
Anyone willing to tell me some PDP parts suppliers that may have some
interface boards, like whatever I need to hook up that RL01 (what exactly
is a RL01 anyways). Maybe I should be looking to add floppy drives, etc.
OR, are people using IBM's as a terminal, and running some program that
pretends to be an attached paper tape reader/punch unit? That might do
for starters, though its not anywhere near as satisfying.
Step zero of course is restoring the line cord and power.
Step one then is to put together a minimal system (8330, 8300, 8310, 8655,
837, 849, Core stack, 8320 bus loads.) You can do some tests with just the
CPU cards in as well.
Step two would be to get RS-232 connectivity to a PC, toggle in the RIM
loader and load some the of the diagnostic tapes. In particular the memory
exerciser and the instruction set tests.
10:06 p.m.
New subject: Next steps (was Re: pdp 8/e)
Make up a positive bus interface and a DMA (data
break) card.
Which is nice. But what does this get me in the real world?
7 Oct
7 Oct
2:22 p.m.
All in all a pretty good catch. While it may be hard to get core for this
thing you can find MOS memory systems at various places. The thing to worry
about will be the top connectors. If you don't have them you can make them
but it isn't fun. Some folks on the pdp8-lovers list might have spares.
Why would it be difficult to make replacement top connectors? I must be
missing something obvious, but cant you just crimp ribbon cable onto
a pair of 36 pin edgeboard connectors? Or dont they make IDC connectors
of the appropriate size?
-Lawrence LeMay
3:42 p.m.
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4:10 p.m.
Hi Lawrence:
At 06:22 PM 10/7/99 -0500, you wrote:
Why would it be difficult to make replacement top
connectors? I must be
missing something obvious, but cant you just crimp ribbon cable onto
a pair of 36 pin edgeboard connectors? Or dont they make IDC connectors
of the appropriate size?
I tried everywhere for these connectors, they are a not-common .125"
spacing. I finally found some at a surplus place in San Diego. Had to drive
1500 miles to get them though!
I can dig out the name of the place, they had lots a few months ago when I
was last there.
If you find IDC connectors in this size/spacing, let me know. I will buy
some too.
Kevin
==========================================================
Sgt. Kevin McQuiggin, Vancouver Police Department
E-Comm Project (604) 215-5095; Cell: (604) 868-0544
Email: mcquiggi(a)sfu.ca
5:42 p.m.
Hi Lawrence:
At 06:22 PM 10/7/99 -0500, you wrote:
You drove 1500 miles to maybe find the correct connector? Did I mention I'm
part owner of the Brooklyn bridge, and could be persuaded to sell my
interests in it for a reasonable fee?
Why would it be difficult to make replacement top
connectors? I must be
missing something obvious, but cant you just crimp ribbon cable onto
a pair of 36 pin edgeboard connectors? Or dont they make IDC connectors
of the appropriate size?
I tried everywhere for these connectors, they are a not-common .125"
spacing. I finally found some at a surplus place in San Diego. Had to drive
1500 miles to get them though!
I can dig out the name of the place, they had lots a few months ago when I
was last there.
If you find IDC connectors in this size/spacing, let me know. I will buy
some too.
Kevin
Were the ones you bought usable with standard IDE ribbon cable? or were
they solder eyelet versions? I see Digikey sells these with solder eyelets,
but the smallest they sell is a 44 connector, and we're looking for 36...
I'm not in immediate need for this, but it would be a great thing to
buy a supply of while they are still available.
-Lawrence LeMay
5:59 p.m.
New subject: DEC Edge Connectors
At 09:42 PM 10/7/99 -0500, you wrote:
You drove 1500 miles to maybe find the correct
connector? Did I mention I'm
part owner of the Brooklyn bridge, and could be persuaded to sell my
interests in it for a reasonable fee?
Well the trip was actually to pick up a dual RX01 floppy drive from John
Lawson in Los Angeles, the trip from LA to San Diego was to visit one of my
friends who lives there.
I found the connectors during a junk scrounge with my friend.
Were the ones you bought usable with standard IDE
ribbon cable? or were
they solder eyelet versions? I see Digikey sells these with solder eyelets,
but the smallest they sell is a 44 connector, and we're looking for 36...
They have 1/2" solder tails, and can be used to make the edge connectors
with a suitable small circuit board. I'll have to make the circuit board
myself.
I'm not in immediate need for this, but it would be
a great thing to
buy a supply of while they are still available.
I can dig up the name of the place if you need it.
Kevin
==========================================================
Sgt. Kevin McQuiggin, Vancouver Police Department
E-Comm Project (604) 215-5095; Cell: (604) 868-0544
Email: mcquiggi(a)sfu.ca
7:25 p.m.
New subject: DEC Edge Connectors
On Thu, 7 Oct 1999, Kevin McQuiggin wrote:
I found the connectors during a junk scrounge with my
friend.
They have 1/2" solder tails, and can be used to make the edge connectors
with a suitable small circuit board. I'll have to make the circuit board
myself.
I can dig up the name of the place if you need it.
Kevin, send me the name of the place and perhaps I can save someone else
a 1500 mile drive :) Be happy to pick some up if I have any idea how
many are wanted.
- don
8 Oct
8 Oct
1:26 a.m.
New subject: DEC Edge Connectors
On Thu, 07 Oct 1999 19:59:30 -0700 Kevin McQuiggin
<mcquiggi(a)sfu.ca> wrote:
At 09:42 PM 10/7/99 -0500, you wrote:
Well, I went from Bristol, UK to Dayton, Ohio (via Boston)
in order to visit a junk emporium and buy:
NIXIE TUBES!!!!
And I even got them back through the airport X-ray machines
without any questions...
--
John Honniball
Email: John.Honniball(a)uwe.ac.uk
University of the West of England
You drove 1500 miles to maybe find the correct
connector?
Well the trip was actually to pick up a dual RX01 floppy drive from John
Lawson in Los Angeles, the trip from LA to San Diego was to visit one of my
friends who lives there.
I found the connectors during a junk scrounge with my friend. 
5:19 a.m.
New subject: DEC Edge Connectors
Upon the date 11:26 AM 10/8/99 +0100, John Honniball said something like:
On Thu, 07 Oct 1999 19:59:30 -0700 Kevin McQuiggin
<mcquiggi(a)sfu.ca> wrote:
I bet you went to Mendelson's, my all-time favorite "Emporium of the
Electronic Junque". I get lost for hours at a time in there whenever I visit.
Regards, Chris
-- --
Christian Fandt, Electronic/Electrical Historian
Jamestown, NY USA cfandt(a)netsync.net
Member of Antique Wireless Association
URL: http://www.antiquewireless.org/
At 09:42 PM 10/7/99 -0500, you wrote:
Well, I went from Bristol, UK to Dayton, Ohio (via Boston)
in order to visit a junk emporium and buy:
NIXIE TUBES!!!!
And I even got them back through the airport X-ray machines
without any questions... You drove 1500 miles to maybe find the correct
connector?
Well the trip was actually to pick up a dual RX01 floppy drive from John
Lawson in Los Angeles, the trip from LA to San Diego was to visit one of my
friends who lives there.
I found the connectors during a junk scrounge with my friend.
6:58 a.m.
New subject: Mendelson's (was: DEC Edge Connectors)
Well, I went
from Bristol, UK to Dayton, Ohio (via Boston)
in order to visit a junk emporium and buy:
NIXIE TUBES!!!!
And I even got them back through the airport X-ray machines
without any questions...
I bet you went to Mendelson's, my all-time favorite "Emporium of the
Electronic Junque". I get lost for hours at a time in there whenever I visit.
Regards, Chris
-- --
Christian Fandt, Electronic/Electrical Historian
8:48 a.m.
New subject: DEC Edge Connectors
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9049
days inactive
9051
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18 comments
9 participants
participants (9)
-
ard＠p850ug1.demon.co.uk -
cfandt＠netsync.net -
cmcmanis＠mcmanis.com -
donm＠cts.com -
eric＠brouhaha.com -
John.Honniball＠uwe.ac.uk -
lemay＠cs.umn.edu -
mcguire＠neurotica.com -
mcquiggi＠sfu.ca