Re: Univac I memory tank

[Cory Heisterkamp via cctalk]

On Mar 15, 2017, at 3:11 AM, Pontus Pihlgren via cctalk wrote:

> On Tue, Mar 14, 2017 at 05:41:57PM -0400, Noel Chiappa via cctalk wrote:
>>> From: Dwight Kelvey
>> 
>>> I need on of those.
>> 
>> I think it belongs in a museum, actually. Provided they can make it work, of
>> course! :-) I wonder how many working delay line main memories are left in
>> the world?
> 
> CHM has one: http://www.computerhistory.org/collections/catalog/X976.89
> 
> It used to be on display, perhaps it still is.
> 
> /P

It appears the external photos associated with the auction were pulled. Is the 
lucky winner on this list? Given the location, I was curious if this came from 
UNIVAC #24 (the last operating UNIVAC I). -C

http://www.ebay.com/itm/Univac-vintage-large-computer-Parts-only-AS-IS-/162428766985

Re: Univac I memory tank

[dwight via cctalk]

If anyone has a Diehl Combitron or one of the NCR versions. I'd love

to have one. I used one years ago while working for UofMiami.

I used it because it could be programmed and did square root.

I can't pay what one is worth but would still love to have one.

Dwight



From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Christian Corti via 
cctalk <cctalk@classiccmp.org>
Sent: Thursday, March 16, 2017 2:22:27 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Univac I memory tank

On Wed, 15 Mar 2017, dwight wrote:
> The Olivetti used a piece of wire for the delay line. I forget what the
> Dielh Combitron used but I know it used a two delay lines. One was for
> registers and the other was for lookup tables that loaded at turn on
> time from a metal tape ( as I recall ).

I can tell you exactly what the Diehl Combitron does; I have a running
bachelor thesis for a student who is developing an emulator and assembler
for that machine, and we have also disassembled (but not yet
understood) the firmware (contained on the metal tape) of the machine.

In fact, it uses two magnetostrictive delay lines, one is called the R
delay line containing 219 bits plus one external in a flip-flop. The other
is called the M delay line with a total of 10889+1 bits. The main clock of
the machine is 1 MHz thus a bit time (called P) is 1 µs.
The R line holds four words à 55 bits, one in the I phase P bits time, one
in the I phase /P bits time, one in the /I phase P bits time and one in
the /I phase /P bits time. The instructions are always fetched from the I
phase /P bits and executed in the /I phase.
The M line holds a total of 99 P words and 99 /P words. The phase between
P and /P changes every M cycle

During the loading phase (e.g. at power on or after a 'e1' order) the R
line is filled with the contents coming from tape and then executed.
Usually the code just transfers the other three words of the R line
somewhere into the M line and restarts the loading phase for the next
block. After loading the last block a fill instruction "jumps" to the
entry point of the firmware. The fill instruction transfers four words
from the M line to the R line.

Christian

Re: Univac I memory tank

[Christian Corti via cctalk]

On Wed, 15 Mar 2017, dwight wrote:
The Olivetti used a piece of wire for the delay line. I forget what the 
Dielh Combitron used but I know it used a two delay lines. One was for 
registers and the other was for lookup tables that loaded at turn on 
time from a metal tape ( as I recall ).


I can tell you exactly what the Diehl Combitron does; I have a running 
bachelor thesis for a student who is developing an emulator and assembler 
for that machine, and we have also disassembled (but not yet 
understood) the firmware (contained on the metal tape) of the machine.


In fact, it uses two magnetostrictive delay lines, one is called the R 
delay line containing 219 bits plus one external in a flip-flop. The other 
is called the M delay line with a total of 10889+1 bits. The main clock of 
the machine is 1 MHz thus a bit time (called P) is 1 µs.
The R line holds four words à 55 bits, one in the I phase P bits time, one 
in the I phase /P bits time, one in the /I phase P bits time and one in 
the /I phase /P bits time. The instructions are always fetched from the I 
phase /P bits and executed in the /I phase.
The M line holds a total of 99 P words and 99 /P words. The phase between 
P and /P changes every M cycle


During the loading phase (e.g. at power on or after a 'e1' order) the R 
line is filled with the contents coming from tape and then executed. 
Usually the code just transfers the other three words of the R line 
somewhere into the M line and restarts the loading phase for the next 
block. After loading the last block a fill instruction "jumps" to the 
entry point of the firmware. The fill instruction transfers four words 
from the M line to the R line.


Christian

Re: Univac I memory tank

[Marc Howard via cctalk]

Adds a whole new dimension to the term "memory leak".

Marc

On Wed, Mar 15, 2017 at 6:32 AM, dwight via cctalk <cctalk@classiccmp.org>
wrote:

> I can't imagine why it needed to be reworked. That is only what I was
> told. I always thought it was kind of funny.
>
> The Olivetti used a piece of wire for the delay line. I forget what the
> Dielh Combitron used but I know it used a two delay lines. One was for
> registers and the other was for lookup tables that loaded at turn on time
> from a metal tape ( as I recall ).
>
> Dwight
>
>
> 
> From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Pontus Pihlgren
> via cctalk <cctalk@classiccmp.org>
> Sent: Wednesday, March 15, 2017 1:11:10 AM
> To: Noel Chiappa; General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: Univac I memory tank
>
> On Tue, Mar 14, 2017 at 05:41:57PM -0400, Noel Chiappa via cctalk wrote:
> > > From: Dwight Kelvey
> >
> > > I need on of those.
> >
> > I think it belongs in a museum, actually. Provided they can make it
> work, of
> > course! :-) I wonder how many working delay line main memories are left
> in
> > the world?
>
> CHM has one: http://www.computerhistory.org/collections/catalog/X976.89
>
> It used to be on display, perhaps it still is.
>
> /P
>

Delay Lines (Was: Univac I memory tank)

[Rick Bensene via cctalk]

Dwight wrote:

> The Olivetti used a piece of wire for the delay line. 

The Programma 101  indeed used a delay line.  Such delay lines use
magnetostrictive means to push a torque pulse into one end of the wire,
as well as detect a torque twist at the other end of the wire.
Magnetostrictive materials are typically a metal alloy that lengthens or
shortens depending on the polarity of an external magnetic field, and
will also generate a small magnetic field if stretched or compressed.

In a magnetostrictive delay line thin strips of magnetostrictive metal
are attached to opposite points tangential to the circumference of the
end of a nickel-alloy(typically) wire.  These strips, for whatever
reason, are typically called "tapes".

Each tape has a small coil of magnet wire surrounding it, wound
oppositely around each tape, such that when a short current pulse is
sent into the coils, one tape momentarily lengthens, and the other tape
contracts, causing a slight but sharp twisting torque to be applied to
the wire. This acts to transmit a pulse of energy into the wire.  The
torque twist mechanically travels through the wire to the other end,
where it causes one tape to lengthen slightly, and the other to compress
slightly, which induces a small current pulse into the coils around the
tapes, which can be amplified to match the electrical characteristics of
the original pulse. Sending a current pulse through the coils in one
direction causes the twist to occur clockwise, and the pulse going the
other direction induces a counter-clockwise twist, allowing ones and
zeros to be pushed into the wire as clockwise or counter-clockwise
torque twists.

The amount of time that elapses (delay)  from the pulse being injected
to being received at the other end of the wire is based on the
metallurgy of the wire, and its length.   The wire is capable of
remembering some number of torque twists  as bits, with a clockwise
torque, for example, representing a one, and a counter-clockwise twist
representing a zero.   

The wire was typically arranged in a spiral inside a metal housing.
Silicone or rubber supports supported the wire without attenuating the
torque pulses in the wire.In some cases, there were "taps" along the
length of the wire that used the same transducer method to pick off bits
at different delay periods. 

The use of such delay line technology in calculators arose  out of the
need to store a moderate number of bits to represent the working
registers of the calculator.  At the time, magnetic core memory was
still quite expensive, integrated circuit technology was in its infancy
and too expensive to use for mass storage in a calculator, and it was
generally cost and size prohibitive to store the bits required in
discrete transistor flip flop storage registers (though a few very early
electronic calculators did use this method).  

Given that delay line technology had been used with success on computers
(though the Univac I delay lines were very different than
magnetostrictive delay lines), they were a low cost, relatively simple
way to provide the small amount of storage required for an electronic
calculator.   A prime example of the use of magnetostrictive delay lines
in a computer was the Packard Bell 250, a low-cost "personal" computer
introduced in the early 1960's.

The bit-serial nature of the delay line was ideal for a calculator,
since a bit serial architecture is coincident with the most efficient
way to make an electronic calculator, where raw speed is not a
requirement, and minimizing the component count saves money.  The serial
nature of the delay line means that if a specific bit is needed, the
logic must wait around for the bit to arrive at the end of the delay
line.   This slows down the operation of the device, but in the case of
a calculator, where results are subject to human perception, 10s to
100's of milliseconds is well within the acceptable time for a
calculation to occur.

> I forget what the Dielh Combitron used but I know it used a two delay
lines. One was for registers and the other was for lookup tables that
loaded at turn on time from a metal tape ( as I recall ).

The Diehl Combitron did use two separate delay lines, one for the
registers(as well as learn-mode program storage) as mentioned, but the
other one wasn't really for lookup tables, but instead stored the
operating microcode that made the machine run.   The microcode was
indeed loaded from a punched metal tape at power-on time.   The
ingenious design of the Combitron was done by Dr. Stanley Frankel, a
nuclear physicist who was deeply involved in the mathematical modeling
that made the atom and hydrogen bombs possible.  After the Manhattan
project ended, he was involved in the design of quite a few computers
and calculators.  Notable computers that he designed were the
Librascope-General Precision LGP-30, the aforementioned Packard Bell
250, and some design work on early General Electric computers.   He also
designed the 

Re: Univac I memory tank

[dwight via cctalk]

I can't imagine why it needed to be reworked. That is only what I was told. I 
always thought it was kind of funny.

The Olivetti used a piece of wire for the delay line. I forget what the Dielh 
Combitron used but I know it used a two delay lines. One was for registers and 
the other was for lookup tables that loaded at turn on time from a metal tape ( 
as I recall ).

Dwight



From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Pontus Pihlgren via 
cctalk <cctalk@classiccmp.org>
Sent: Wednesday, March 15, 2017 1:11:10 AM
To: Noel Chiappa; General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Univac I memory tank

On Tue, Mar 14, 2017 at 05:41:57PM -0400, Noel Chiappa via cctalk wrote:
> > From: Dwight Kelvey
>
> > I need on of those.
>
> I think it belongs in a museum, actually. Provided they can make it work, of
> course! :-) I wonder how many working delay line main memories are left in
> the world?

CHM has one: http://www.computerhistory.org/collections/catalog/X976.89

It used to be on display, perhaps it still is.

/P

Re: Univac I memory tank

[Pontus Pihlgren via cctalk]

On Tue, Mar 14, 2017 at 05:41:57PM -0400, Noel Chiappa via cctalk wrote:
> > From: Dwight Kelvey
> 
> > I need on of those.
> 
> I think it belongs in a museum, actually. Provided they can make it work, of
> course! :-) I wonder how many working delay line main memories are left in
> the world?

CHM has one: http://www.computerhistory.org/collections/catalog/X976.89

It used to be on display, perhaps it still is.

/P

Re: Univac I memory tank

[Adrian Stoness via cctalk]

The mercury also gets dirty from its own oxidization

On Mar 14, 2017 5:00 PM, "Ben Sinclair via cctalk" 
wrote:

> On Tue, Mar 14, 2017 at 4:41 PM, Noel Chiappa via cctalk <
> cctalk@classiccmp.org> wrote:
>
> > I think it belongs in a museum, actually. Provided they can make it work,
> > of
> > course! :-) I wonder how many working delay line main memories are left
> in
> > the world?
> >
>
> If that's from a Univac I, I'd love to see it in a museum as well!
> According to Wikipedia there were only 18 Univac I installations, so this
> is a pretty rare piece.
>
>
> --
> Ben Sinclair
> b...@bensinclair.com
>

Re: Univac I memory tank

[Ben Sinclair via cctalk]

On Tue, Mar 14, 2017 at 4:41 PM, Noel Chiappa via cctalk <
cctalk@classiccmp.org> wrote:

> I think it belongs in a museum, actually. Provided they can make it work,
> of
> course! :-) I wonder how many working delay line main memories are left in
> the world?
>

If that's from a Univac I, I'd love to see it in a museum as well!
According to Wikipedia there were only 18 Univac I installations, so this
is a pretty rare piece.


-- 
Ben Sinclair
b...@bensinclair.com

Re: Univac I memory tank

[Paul Koning via cctalk]

> On Mar 14, 2017, at 5:45 PM, dwight via cctalk  wrote:
> 
> It is not likely to be made to work, easily. From what I was
> told, the mercury ones needed to be rebuilt after some time.
> Most likely because the mercury dissolved one of the metals
> used in side.
> 
> I can't imagine what that might be and why they continued
> to have such a problem but that is what I hear someplace.
> 
> Dwight

Possible, but it seems odd.  Mercury dissolves lots of metals (iron is one 
exception), forming alloys called amalgams.  But that's well known, you would 
expect people making mercury based devices to know it and avoid it.

paul

Re: Univac I memory tank

[dwight via cctalk]

It is not likely to be made to work, easily. From what I was

told, the mercury ones needed to be rebuilt after some time.

Most likely because the mercury dissolved one of the metals

used in side.

I can't imagine what that might be and why they continued

to have such a problem but that is what I hear someplace.

Dwight



From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Noel Chiappa via 
cctalk <cctalk@classiccmp.org>
Sent: Tuesday, March 14, 2017 2:41:57 PM
To: cctalk@classiccmp.org
Cc: j...@mercury.lcs.mit.edu
Subject: Re: Univac I memory tank

> From: Dwight Kelvey

> I need on of those.

I think it belongs in a museum, actually. Provided they can make it work, of
course! :-) I wonder how many working delay line main memories are left in
the world?

Noel

PS: Sorry about the previous mostly-duplicate message; I hit the 'interrupt'
key and it did the wrong thing.

Re: Univac I memory tank

[Ian S. King via cctalk]

On Tue, Mar 14, 2017 at 11:21 AM, Adrian Stoness via cctalk <
cctalk@classiccmp.org> wrote:

> its been pulled
>
> It's still there when I click on the link, five days to go.  Boy howdy,
this would be a headache to get shipped!  Even if the mercury is gone,
there are almost certain to be residuals.  -- Ian

-- 
Ian S. King, MSIS, MSCS, Ph.D. Candidate
The Information School 
Dissertation: "Why the Conversation Mattered: Constructing a Sociotechnical
Narrative Through a Design Lens

Archivist, Voices From the Rwanda Tribunal 
Value Sensitive Design Research Lab 

University of Washington

There is an old Vulcan saying: "Only Nixon could go to China."

Re: Univac I memory tank

[Adrian Stoness via cctalk]

its been pulled

On Tue, Mar 14, 2017 at 1:18 PM, Zane Healy via cctalk <
cctalk@classiccmp.org> wrote:

> What scares me the most is that there are already 4 bids on it.
>
> Zane
>
>
>
>
> > On Mar 14, 2017, at 11:16 AM, dwight via cctalk <cctalk@classiccmp.org>
> wrote:
> >
> > Cool. I need on of those.
> >
> > Dwight
> >
> >
> > 
> > From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Al Kossow via
> cctalk <cctalk@classiccmp.org>
> > Sent: Tuesday, March 14, 2017 10:20:00 AM
> > To: General Discussion: On-Topic and Off-Topic Posts
> > Subject: Univac I memory tank
> >
> > http://www.ebay.com/itm/162428766985
> >
> > Asked if the mercury was still in it. They ignored me.
> >
>
>

Re: Univac I memory tank

[Zane Healy via cctalk]

What scares me the most is that there are already 4 bids on it.

Zane




> On Mar 14, 2017, at 11:16 AM, dwight via cctalk <cctalk@classiccmp.org> wrote:
> 
> Cool. I need on of those.
> 
> Dwight
> 
> 
> 
> From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Al Kossow via 
> cctalk <cctalk@classiccmp.org>
> Sent: Tuesday, March 14, 2017 10:20:00 AM
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Univac I memory tank
> 
> http://www.ebay.com/itm/162428766985
> 
> Asked if the mercury was still in it. They ignored me.
> 

Re: Univac I memory tank

[dwight via cctalk]

Cool. I need on of those.

Dwight



From: cctalk <cctalk-boun...@classiccmp.org> on behalf of Al Kossow via cctalk 
<cctalk@classiccmp.org>
Sent: Tuesday, March 14, 2017 10:20:00 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Univac I memory tank

http://www.ebay.com/itm/162428766985

Asked if the mercury was still in it. They ignored me.

Univac I memory tank

[Al Kossow via cctalk]

http://www.ebay.com/itm/162428766985

Asked if the mercury was still in it. They ignored me.