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Today's Topics:
1. Re: DEC PDP-8/e H212 core mat repair ([email protected])
2. Re: DEC PDP-8/e H212 core mat repair (Joshua Rice)
3. Re: DEC PDP-8/e H212 core mat repair (Joshua Rice)
4. Re: DEC PDP-8/e H212 core mat repair (Tom Hunter)
5. Re: DEC PDP-8/e H212 core mat repair (Jules Richardson)
6. Re: DEC PDP-8/e H212 core mat repair (Rod Smallwood)
7. Tektronix 8002 microprocessor lab software (Jules Richardson)
8. Re: Tektronix 8002 microprocessor lab software (Zane Healy)
9. Re: Tektronix 8002 microprocessor lab software (Al Kossow)
10. Re: Tektronix 8002 microprocessor lab software (Al Kossow)
11. Re: Tektronix 8002 microprocessor lab software (Al Kossow)
12. Re: Tektronix 8002 microprocessor lab software (Jules Richardson)
13. Re: Tektronix 8002 microprocessor lab software (Jules Richardson)
14. Re: Tektronix 8002 microprocessor lab software (Zane Healy)
15. Re: Items Wanted (Jay Jaeger)
16. Re: Items Wanted (Zane Healy)
17. Re: DEC PDP-8/e H212 core mat repair (Toby Thain)
----------------------------------------------------------------------
Message: 1
Date: Mon, 19 Jul 2021 17:59:59 +1000
From: [email protected]
To: "General Discussion: On-Topic and Off-Topic Posts"
<[email protected]>
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID:
<[email protected]>
Content-Type: text/plain;charset=utf-8
Tom said
I am curious if anyone has attempted to repair (replace) a broken wire
in a
PDP-8/e H212 (MM8EJ) core mat (8 k word). The cores are not visible
without
a microscope. I cannot imagine how these were even manufactured and
wonder
if DEC service centers repaired core mat faults or if faulty boards
were
simply discarded.
CDC 6600 cores were huge in comparison and I would not hesitate to
replace
a broken core wire on those.
I have no idea how DEC made theirs but for IBM's System 360, one of
their engineers
came up with the clever idea of stretching the core wire so it necked
and broke, leaving
a work-hardened tapered point to thread the cores with.
They patented it https://patents.google.com/patent/US3314131A
(Source: page 187 of 'IBM's 360 and early 370 Systems' by Pugh et al)
On a Youtube film about the 360 they show cores being vibrated into the
correct
orientation on a jig board.
------------------------------
Message: 2
Date: Mon, 19 Jul 2021 09:40:44 +0100 (BST)
From: Joshua Rice <[email protected]>
To: CCtalk <[email protected]>
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID: <[email protected]>
Content-Type: text/plain; charset=UTF-8; format=flowed
------ Original Message ------
From: "Tom Hunter via cctalk" <[email protected]>
To: "General Discussion: On-Topic and Off-Topic Posts"
<[email protected]>
Sent: Monday, 19 Jul, 2021 At 06:33
Subject: DEC PDP-8/e H212 core mat repair
I am curious if anyone has attempted to repair (replace) a broken wire
in a
PDP-8/e H212 (MM8EJ) core mat (8 k word). The cores are not visible
without
a microscope. I cannot imagine how these were even manufactured and
wonder
if DEC service centers repaired core mat faults or if faulty boards
were
simply discarded.
CDC 6600 cores were huge in comparison and I would not hesitate to
replace
a broken core wire on those.
Best regards
Tom Hunter
I believe much of the core manufacturing for DEC minicomputers was
outsourced, but a lot of it had become much more automated by the late
60's and early 70's. I believe it was done by machine, with a tray to
hold the toroids in place, and a very fine needle-like "bobbin" that
threaded the wires through the toroids. I believe threading the cores
by
hand had become largely obsolete by the time the PDP-8 came onto the
market.
Though i can't confirm it, i highly doubt that DEC engineers would
repair core planes. These would more likely be sent back to the
manufacturer for "recycling", with the cores being recovered and
reused.
It's worth noting that most computer manufacturers appreciated the
fragility of core memory planes at the time, with most of them being
protected with either PCB's or perspex/plastic shields on top of the
core planes. In this way, it was rather difficult for a clumsy ol'
technician to put his thumb through the planes as he was servicing
machines.
Josh
------------------------------
Message: 3
Date: Mon, 19 Jul 2021 09:52:13 +0100 (BST)
From: Joshua Rice <[email protected]>
To: CCtalk <[email protected]>
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID: <[email protected]>
Content-Type: text/plain; charset=UTF-8; format=flowed
------ Original Message ------
From: "Tom Hunter via cctalk" <[email protected]>
To: "General Discussion: On-Topic and Off-Topic Posts"
<[email protected]>
Sent: Monday, 19 Jul, 2021 At 06:33
Subject: DEC PDP-8/e H212 core mat repair
I am curious if anyone has attempted to repair (replace) a broken wire
in a
PDP-8/e H212 (MM8EJ) core mat (8 k word). The cores are not visible
without
a microscope. I cannot imagine how these were even manufactured and
wonder
if DEC service centers repaired core mat faults or if faulty boards
were
simply discarded.
CDC 6600 cores were huge in comparison and I would not hesitate to
replace
a broken core wire on those.
Best regards
Tom Hunter
These patents might be enlightening. I'm sure there's others, but these
are some i've found on a quick search.
https://patents.google.com/patent/US4161037A
<https://patents.google.com/patent/US4161037A>
https://patents.google.com/patent/US3668664
<https://patents.google.com/patent/US3668664>
Josh
------------------------------
Message: 4
Date: Mon, 19 Jul 2021 19:02:25 +0800
From: Tom Hunter <[email protected]>
To: Joshua Rice <[email protected]>, "General Discussion:
On-Topic and Off-Topic Posts" <[email protected]>
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID:
<CAALEduCP_GLHuuMG2UO3CU329-_3E=rpqzvz+rugc6gtvqn...@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Thanks Josh,
I read through both patents but struggled to fully understand what they
described.
Unfortunately patents are written in broad terms to cover as much as
possible.
It was very interesting nevertheless.
Best regards
Tom Hunter
On Mon, Jul 19, 2021 at 4:52 PM Joshua Rice via cctalk <
[email protected]> wrote:
------ Original Message ------
From: "Tom Hunter via cctalk" <[email protected]>
To: "General Discussion: On-Topic and Off-Topic Posts"
<[email protected]>
Sent: Monday, 19 Jul, 2021 At 06:33
Subject: DEC PDP-8/e H212 core mat repair
I am curious if anyone has attempted to repair (replace) a broken wire
in a
PDP-8/e H212 (MM8EJ) core mat (8 k word). The cores are not visible
without
a microscope. I cannot imagine how these were even manufactured and
wonder
if DEC service centers repaired core mat faults or if faulty boards
were
simply discarded.
CDC 6600 cores were huge in comparison and I would not hesitate to
replace
a broken core wire on those.
Best regards
Tom Hunter
These patents might be enlightening. I'm sure there's others, but
these
are some i've found on a quick search.
https://patents.google.com/patent/US4161037A
<https://patents.google.com/patent/US4161037A>
https://patents.google.com/patent/US3668664
<https://patents.google.com/patent/US3668664>
Josh
------------------------------
Message: 5
Date: Mon, 19 Jul 2021 16:50:10 -0500
From: Jules Richardson <[email protected]>
To: [email protected]
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
On 7/19/21 3:40 AM, Joshua Rice via cctalk wrote:
I believe much of the core manufacturing for DEC minicomputers was
outsourced, but a lot of it had become much more automated by the late
60's
and early 70's.
I've got a trio of planes here, two of which are from a Lockheed
MAC-16,
but the other one is made by Keronix out of Santa Monica for an unknown
machine (dated 1973, model number "P4" and p/n 816335 if that means
anything to anyone, approx 16"x16" with two 100-pin, double-sided
finger
edge connectors on 0.1" spacing).
Anyhoo, the Keronix one has a sticker on it saying it was repaired by
DMA,
inc. in Amery, WI in 1980 - which might suggest that there were third
parties around working on boards, rather than them having to go back to
the
manufacturer for repair. (I have no idea what the nature of the repair
was,
of course; maybe it was to surrounding logic rather than the mat
itself).
It's worth noting that most computer manufacturers appreciated the
fragility of core memory planes at the time, with most of them being
protected with either PCB's or perspex/plastic shields on top of the
core
planes.
Yes, that's how all the ones I've ever seen have been. The Keronix one
has
an additional shield over the top of the entire PCB, on top of the one
protecting the cores.
Jules
------------------------------
Message: 6
Date: Mon, 19 Jul 2021 23:06:26 +0100
From: Rod Smallwood <[email protected]>
To: Jules Richardson via cctalk <[email protected]>
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
Yes most core stringing was outsourced.
By hand under magnification was used.
I cant recall any references to automation.
That would br down to the supplier.
The story I heard was at least some were done by embroidery girls in
Hong Kong
Rod Smallwood ? -- Digital Equipment Corporation? 1975 to 1985
On 19/07/2021 22:50, Jules Richardson via cctalk wrote:
On 7/19/21 3:40 AM, Joshua Rice via cctalk wrote:
I believe much of the core manufacturing for DEC minicomputers was
outsourced, but a lot of it had become much more automated by the
late 60's and early 70's.
I've got a trio of planes here, two of which are from a Lockheed
MAC-16, but the other one is made by Keronix out of Santa Monica for
an unknown machine (dated 1973, model number "P4" and p/n 816335 if
that means anything to anyone, approx 16"x16" with two 100-pin,
double-sided finger edge connectors on 0.1" spacing).
Anyhoo, the Keronix one has a sticker on it saying it was repaired by
DMA, inc. in Amery, WI in 1980 - which might suggest that there were
third parties around working on boards, rather than them having to go
back to the manufacturer for repair. (I have no idea what the nature
of the repair was, of course; maybe it was to surrounding logic rather
than the mat itself).
It's worth noting that most computer manufacturers appreciated the
fragility of core memory planes at the time, with most of them being
protected with either PCB's or perspex/plastic shields on top of the
core planes.
Yes, that's how all the ones I've ever seen have been. The Keronix one
has an additional shield over the top of the entire PCB, on top of the
one protecting the cores.
Jules
------------------------------
Message: 7
Date: Mon, 19 Jul 2021 18:03:46 -0500
From: Jules Richardson <[email protected]>
To: CCtalk <[email protected]>
Subject: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
Just out of interest, is the software for the Tektronix 8002
microprocessor
lab archived out there anywhere?
What I believe is one popped up on one of my Facebook groups, and it'd
be a
trek to get it even if I can arrange a good price with the current
owner -
but it sounds like the software at the site, if it still exists, is
unlikely to surface from a huge pile of detritus, so that automatically
puts things right in boat anchor territory.
There may or may not be a terminal, too; I get the impression those
were
optional (I've been told that there are two Tek terminals, I just don't
know if they're the right models for this system).
cheers
Jules
------------------------------
Message: 8
Date: Mon, 19 Jul 2021 16:11:32 -0700
From: Zane Healy <[email protected]>
To: Jules Richardson <[email protected]>, "General
Discussion: On-Topic and Off-Topic Posts" <[email protected]>
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8
You might check with the Tektronix museum, and see what they know. As
far as I know, they aren?t actually part of Tektronix.
Zane
On Jul 19, 2021, at 4:03 PM, Jules Richardson via cctalk
<[email protected]> wrote:
Just out of interest, is the software for the Tektronix 8002
microprocessor lab archived out there anywhere?
What I believe is one popped up on one of my Facebook groups, and it'd
be a trek to get it even if I can arrange a good price with the
current owner - but it sounds like the software at the site, if it
still exists, is unlikely to surface from a huge pile of detritus, so
that automatically puts things right in boat anchor territory.
There may or may not be a terminal, too; I get the impression those
were optional (I've been told that there are two Tek terminals, I just
don't know if they're the right models for this system).
cheers
Jules
------------------------------
Message: 9
Date: Mon, 19 Jul 2021 16:15:11 -0700
From: Al Kossow <[email protected]>
To: Jules Richardson via cctalk <[email protected]>
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
On 7/19/21 4:03 PM, Jules Richardson via cctalk wrote:
Just out of interest, is the software for the Tektronix 8002
microprocessor lab archived out there anywhere?
I have some but it is hard-sectored so I've never tried to read it.
It's pretty unlikely anyone at the tek museum would have tried to
recover
the floppies even if they had them.
One of my 'really like to try to recover' things at CHM is we have a
bunch of floppies from
the company that designed it for Tek, but someone put a center punch
through every disk, so
I'm going to have to take them out of the jacket and try to flatten
the dent out as best as
I can.
------------------------------
Message: 10
Date: Mon, 19 Jul 2021 16:20:19 -0700
From: Al Kossow <[email protected]>
To: [email protected]
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
On 7/19/21 4:03 PM, Jules Richardson via cctalk wrote:
Just out of interest, is the software for the Tektronix 8002
microprocessor lab archived out there anywhere?
It would be nice to save a complete system though, since most have
been tossed out since there is little
practical use for them now. I never had a whole one, just board sets
for various processors that I collected
over the years.
------------------------------
Message: 11
Date: Mon, 19 Jul 2021 16:25:21 -0700
From: Al Kossow <[email protected]>
To: Al Kossow via cctalk <[email protected]>
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
On 7/19/21 4:20 PM, Al Kossow via cctalk wrote:
On 7/19/21 4:03 PM, Jules Richardson via cctalk wrote:
It would be nice to save a complete system though, since most have
been tossed out since there is little
practical use for them now.
I've collected a LOT of in-circuit emulators and microprocessor
development systems over the decades, and
I'm trying to decide right now what I'm going to do with them.
------------------------------
Message: 12
Date: Mon, 19 Jul 2021 19:53:25 -0500
From: Jules Richardson <[email protected]>
To: [email protected]
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
On 7/19/21 6:20 PM, Al Kossow via cctalk wrote:
On 7/19/21 4:03 PM, Jules Richardson via cctalk wrote:
Just out of interest, is the software for the Tektronix 8002
microprocessor lab archived out there anywhere?
It would be nice to save a complete system though, since most have
been
tossed out since there is little
practical use for them now.
Well sadly it's looking like game over. By the sounds of it there's a
basement full of old equipment and boards, and a scrapper out in OH has
offered $6k for the lot, sight unseen, just on the hope that they can
make
a buck on the gold and palladium content.
The next offer seems to be from someone who's planning on just dumping
it
on ebay - so if the scrapper deal falls through maybe it'll resurface
on
That Auction Site for lolprice...
This is starting to feel like one of those situations where it's a huge
shame that the original owner of this stuff didn't have a will
expressing
what should be done with it all.
------------------------------
Message: 13
Date: Mon, 19 Jul 2021 20:17:27 -0500
From: Jules Richardson <[email protected]>
To: [email protected]
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15; format=flowed
On 7/19/21 7:53 PM, Jules Richardson via cctalk wrote:
Well sadly it's looking like game over. By the sounds of it there's a
basement full of old equipment and boards, and a scrapper out in OH
has
offered $6k for the lot, sight unseen, just on the hope that they can
make
a buck on the gold and palladium content.
annnnd... right after I hit send on that, things start looking up
again.
The guy responsible for this stuff doesn't seem to want it to get
scrapped
any more than I do, and he got in touch with folks down at Cape
Canaveral
(there are various ex-NASA things in the pile), then talked to the
family
of the estate; it sounds like some of it at least might get donated to
the
collection down there.
I'm not sure about non-NASA things at this point, we'll see - but it
sounds
like there's interest now in not junking it, at least!
Jules
------------------------------
Message: 14
Date: Mon, 19 Jul 2021 19:56:29 -0700
From: Zane Healy <[email protected]>
To: Jules Richardson <[email protected]>, "General
Discussion: On-Topic and Off-Topic Posts" <[email protected]>
Subject: Re: Tektronix 8002 microprocessor lab software
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8
On Jul 19, 2021, at 6:17 PM, Jules Richardson via cctalk
<[email protected]> wrote:
On 7/19/21 7:53 PM, Jules Richardson via cctalk wrote:
Well sadly it's looking like game over. By the sounds of it there's a
basement full of old equipment and boards, and a scrapper out in OH
has offered $6k for the lot, sight unseen, just on the hope that they
can make a buck on the gold and palladium content.
annnnd... right after I hit send on that, things start looking up
again. The guy responsible for this stuff doesn't seem to want it to
get scrapped any more than I do, and he got in touch with folks down
at Cape Canaveral (there are various ex-NASA things in the pile), then
talked to the family of the estate; it sounds like some of it at least
might get donated to the collection down there.
I'm not sure about non-NASA things at this point, we'll see - but it
sounds like there's interest now in not junking it, at least!
Jules
That?s a bit of good news!
Zane
------------------------------
Message: 15
Date: Mon, 19 Jul 2021 22:03:49 -0500
From: Jay Jaeger <[email protected]>
To: [email protected]
Cc: "General Discussion: On-Topic and Off-Topic Posts"
<[email protected]>
Subject: Re: Items Wanted
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8; format=flowed
On 7/11/2021 9:33 AM, Eric Moore via cctalk wrote:
Hello, I am looking for any of the following items. I have terminals
and
assorted qbus and S100 cards for trade, or am happy to discuss payment
:).
1) Qbus scsi card
You and me both. ;) I have one - and I intend to keep it.
2) Emulex TC01
3) QBUS bus probe
4) SD2SCSI
Do you mean a device that emulates a SCSI drive with an SD card? Why
not just go out and purchase a SCSI2SD V5.1 - a little slower than the
newer ones, but works fine in my Sun, SGI and Intergraph Boxen.
I also just bought one of the less expensive Androda SCSI emulators -
designed for Macs, really, but it might work and it is relatively
inexpensive.
5) Teletype DRPE or ARPE (already have a BRPE) paper tape punches
6) AED/tektronix/SGI/etc... graphics terminal
FYI, if you have "Pizza Boxes" then I have found that the cable
commonly
available (VGA one end, 13W3 on the other - the one with switches on
it)
works well on both Sun and SGI Boxen. Google Sun VGA 13W3 on eBay.
You probably want the one with the switches.)
7) Unfomatted pertec controller (any bus)
I have some old Pertec formatters that have no bus interface. Free to
good homes. Some were mouse houses for a while, but were subsequently
cleaned up reasonably well. Models F649-72 (2 of those) and F649-40.
Heavy to ship.
In addition, I think I have a TC031, Pertec/QBus (I think) that I
really
am not using. I tried it out once - I think the issue was that I had a
Pertec interface speed mismatch between it and the HP drive I have with
a Pertec interface (which also has issues with loading tape.) I
suspect it is formatted, however.
8) S100 jade bus probe, system monitor board, or similar
9) Anything fabri-tek, Gould, or SEL
I have a Fabritek memory box. I think it was on a PDP-12, but am not
100% certain without going back and looking at old paperwork. I am not
sure of its condition, electrically speaking - whether it had slots for
cables, or cables coming out of it, and if the latter, whether they are
intact. It has been stored in my basement for decades, low and dray.
That would take some work to pry out of my hands.
10) blinkenlights and flippenpaddles computers, any interesting front
panels, etc...
11) ESDI disk emulator
I am not aware of any such beasties in the wild. MFM, yes, but I
haven't seen ESDI. I would love for such a thing to exist, thinking
of
my Apollo, 3B2 and IBM RT/PC workstations.
Thank you!
-Eric
------------------------------
Message: 16
Date: Mon, 19 Jul 2021 21:00:27 -0700
From: Zane Healy <[email protected]>
To: Jay Jaeger <[email protected]>, "General Discussion: On-Topic and
Off-Topic Posts" <[email protected]>
Subject: Re: Items Wanted
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8
On Jul 19, 2021, at 8:03 PM, Jay Jaeger via cctalk
<[email protected]> wrote:
On 7/11/2021 9:33 AM, Eric Moore via cctalk wrote:
Hello, I am looking for any of the following items. I have terminals
and
assorted qbus and S100 cards for trade, or am happy to discuss
payment :).
1) Qbus scsi card
You and me both. ;) I have one - and I intend to keep it.
Yeah, they are sort of a necessity.
4) SD2SCSI
Do you mean a device that emulates a SCSI drive with an SD card? Why
not just go out and purchase a SCSI2SD V5.1 - a little slower than the
newer ones, but works fine in my Sun, SGI and Intergraph Boxen.
The SCSI2SD v5.1 should be faster than the Q-Bus. I bought several
recently, and plan to put one in my PDP-11/73. I even opted for these
for my VAXstation 4000?s. I figure I?ll use the newer ones in an
AlphaStation.
11) ESDI disk emulator
I am not aware of any such beasties in the wild. MFM, yes, but I
haven't seen ESDI. I would love for such a thing to exist, thinking
of my Apollo, 3B2 and IBM RT/PC workstations.
I?d also love to have one of these, preferably using SD or CF cards.
The Webster WQESD/04 card is a fantastic card, it?s only downfall is
that it works with ESDI drives, rather than SCSI, and they?re big and
loud. :-)
Zane
------------------------------
Message: 17
Date: Mon, 19 Jul 2021 18:16:28 -0400
From: Toby Thain <[email protected]>
To: "General Discussion: On-Topic and Off-Topic Posts"
<[email protected]>
Subject: Re: DEC PDP-8/e H212 core mat repair
Message-ID: <[email protected]>
Content-Type: text/plain; charset=iso-8859-15
On 2021-07-19 6:06 p.m., Rod Smallwood via cctalk wrote:
Yes most core stringing was outsourced.
There's more detail on early core production in the book "IBM's Early
Computers", iirc. (And possibly "A Few Good Men From Univac".)
...
Rod Smallwood ? -- Digital Equipment Corporation? 1975 to 1985
On 19/07/2021 22:50, Jules Richardson via cctalk wrote:
On 7/19/21 3:40 AM, Joshua Rice via cctalk wrote:
I believe much of the core manufacturing for DEC minicomputers was
outsourced, but a lot of it had become much more automated by the
late 60's and early 70's.
I've got a trio of planes here, two of which are from a Lockheed
MAC-16, but the other one is made by Keronix out of Santa Monica for
an unknown machine (dated 1973, model number "P4" and p/n 816335 if
that means anything to anyone, approx 16"x16" with two 100-pin,
double-sided finger edge connectors on 0.1" spacing).
Anyhoo, the Keronix one has a sticker on it saying it was repaired by
DMA, inc. in Amery, WI in 1980 - which might suggest that there were
third parties around working on boards, rather than them having to go
back to the manufacturer for repair. (I have no idea what the nature
of the repair was, of course; maybe it was to surrounding logic
rather
than the mat itself).
It's worth noting that most computer manufacturers appreciated the
fragility of core memory planes at the time, with most of them being
protected with either PCB's or perspex/plastic shields on top of the
core planes.
Yes, that's how all the ones I've ever seen have been. The Keronix
one
has an additional shield over the top of the entire PCB, on top of
the
one protecting the cores.
Jules
End of cctech Digest, Vol 82, Issue 15
**************************************
