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1401 Demo Lab Renovation and Grand Opening

Table of Contents


Physical plans made and approved Jan 2013 to June 2013
Volunteer Buy In - or presentation to volunteers
Gary Matsushita, CHM Vice President of Operations, far right, tells of efforts to get plans approved by Planning Commission-
Stan Paddock (plaid replaced white shirt) and Robert Garner have written and drawn a lot -
The "IBM Uniforms" are from a previous group picture ;-))
Intense interest was evident about many things - the clearance for repair of the Liebert air conditioner, 50 Hz converter, ... traffic flow (which door should be main entrance - 1st door or door at end of hallway), ...
Permit set Package sent to City of Mountain View, dated March 22, 2013

higher resolution
From supplied .pdf "1401FloorPlanRev5-Jan24" which is a small part of the packet under review by the Mountain View Planning Commission -
They are more interested in ramp width, doors, sprinklers, wheel chair access, bathrooms, and other structeral and environmental conditions.
Artist conception
1401 Demo Room - Exterior
Wall mural is from photos of Toronto Data Center
Note the accent on youth ;-))
Artist conception, with volunteer input
This proposed first view shows the "unit record" equipment which preceeded electronic computers including the IBM 1401.
Artist conception, with volunteer input
The two 1401s
Suggestions in presentation, reverse one, console near visitors
Artist conception, with volunteer input
This shows people coming in the proposed 1401 room exit, the first door you pass on the way to the 1401 room entrance

Current Schedule and developmental dialogs ;-)) - All in 2013 - "V" indicates "Complete"
June 26:  V Shutdown the 1401 systems and prepare them and equipment/tools for storage.
July 15 - 21:  V
Contractors move all 1401 units and boxes into temporary storage in Cyclops (the former visible storage area)
July 17 - 22:  V Contractors build out the new 1401/PDP-1/RAMAC workshop, the "Exhibits Maintenance Room" (apportioned from Cyclops doc storage).
July 22 - Sept 27:   V Contractors teardown and remodel the 1401 room
------------------- pictures taken August 7, 2013 ---------------
the first move-in day for our new workshop!
------------------- status about August 10, 2013 ----------------
" The construction team is moving FAST!! (This is a small, simple, easy project for 'em - they're accustomed to working on entire buildings! ;-)"

"Bob Erickson & Bill Newman working on the Williams Tube memory in the New Shop :-))"

------------------- status August 21, 2013 ----------------
"Photo of the 1401 room on Weds. The electrical is ready, outside new wall is installed and the raised floor is done (they found matching tiles and have reserved ~30 for spares, incl our old ones with holes). Installing lighting now.
"They appear to be about a week ahead of schedule!"

The new back wall is not constructed yet.

------------------- status Sept 9, 2013 ----------------
The back wall was not constructed in the planned position, compressing the already overly-tight presentation area.

Blue tape on floor for the originally planned 6-foot wide walkway, at our request, narrowed to 5.5 and then 5 feet, compatible with building codes.

Options ???

To the right is a proposal leaving out the "unit record" equipment

---------- developmental dialogs ;-)) Sept 12, 2013, from Robert Garner ----------------
During today's engaging ;-) discussion, out of which emerged the suggestion to place the 1406s on both sides of the string of 729 tape drives, move the 729s closer together (apologies Allen*) and given the room dimensions I took this afternoon, this resulted in enough space to place the 083 sorter, 077 collator, and the 513 reproducing punch next to the three 026s, in an area dedicated to punched card equipment.

Here's the latest floorplan (on a more accurate rendering of the room as it was built out -- still in need of a few tweaks/verification): Also note the additional code surprise: the ramp up on right side is in two sections, with the upper section 6 feet wide, then narrowing to 5 feet width. So instead of 16'6" of room depth, it's 15'8" on the right side, resulting in a rotation of the 1402 (or else it's too close to the rail for front access.

The left 1401 would be the primary Connecticut demo system, the right 1401 the Deutsch "logic training"/demo alternate system. Note that visitors will enter on the right side. This plan is similar to the original rendition (minus one 026, one 729, a potential 402, and a 1311).

The clearance above the Liebert is 33". Our punched card cabinet is 26" wide.
Cheers, - Robert
* This floor plan shows 30" of clearance in front, 20" in back for the 729s.

---------- developmental dialogs ;-)) Is this counter culture?? -- from Stan Sept 12, ------------
If you missed the addition, follow the red arrow ;-))

Note that the "unit record" equipment is near the entrance

---------- developmental dialogs ;-)) Why display 2 1401s ?? -- response by Robert Sept 13, ------------
> from Dag,
> I'm curious why we are displaying two 1401s.

  1. Main reason: For live demos, one system is a backup for the other when one is down, especially if it's down for an extended period, for whatever nefarious, hard-to-discover reason.*

  2. One system is a training system to continue to teach (younger ;-) 1401 volunteers on how to maintain and keep our complex systems going.**

  3. When debugging one system, it's efficacious (and, again, a good teaching approach) to have another system to compare behavior/signals against.

  4. A large group of visitors can spread out ~50 feet (on the 5' walkway) and still be in front of /close to seeing the equipment. We'll sometimes might even have both systems on when visitors are in the room.

  5. If one system becomes mothballed, it would drift into disrepair. It was not uncommon to have multiple 1401s at a large customer site, so displaying two is historically authentic. In addition, our wall of seven tape drives makes an impressive presentation (in lieu of displaying a 7090 / 7070. ;-). As we know, 729s were an iconic emblem of 1960s mainframes.
A goal is to keep the "The 1401 Experience" running as a working system for a long time. This newest floorplan should meet everyone's goals.

Cheers, - Robert

* The mean time to failure of one 1401 system has been about 2-3 months, typically due to an issue in the 1402 card reader, which can be fickle. At some point, we may need to take one 1402 down for an extended period to rejuvenate its mechanicals. One of our 1403 printers also needs some more significant maintenance. Also, we can't forget that there are about half a million discrete components in one of our 1401 systems! :-)

** An effective training approach is to introduce a fault in the training system, such as remove a card, and ask the trainee to shoot the bug. This would be dicey to do on the primary demo system. We also could accidentally disable one system just doing vanilla maintenance, such as cleaning cards, something we've accidentally done. :-( There is also interest in learning how to do voltage margining on a 1401.

p.s. One question the 1401 guys ask is "Why the back wall?", esp when we lost nearly 2' when the Liebert wasn't moved out of the way (to save $15k). I explain that the system display is more impressive, as IBM perfected in its 1960s glass houses, when the lines are symmetrical and not visual distracting. I would rather remove the wall than have only one 1401 system.

---------- developmental dialogs ;-)) Packing 729s together -- from Stan Sept 13, ------------
There has been *considerable* dialog about placement of the 729 tape units, and their side to side clearance - if any - for maintenance. (There is no question about needing some 30" rear clearance !! )

Stan made a Web Page showing that at many/most commercial sites, the tape units had effectively no side clearance. (Early in the restoration we needed side clearance for:
- serious circuit breaker problems
- restoring all the clutches )

(If you need side clearance for maintenance, ?rare?, you could disconnect the tape unit, slide it forward, re-connect it for service and testing - ... )

---------- Room status Sept 15, 2013 -------------------------------
From left side towards entrance... From left side of walkway towards entrance Right entrance ramps

---------- developmental dialogs ;-)) -- from Robert Sept 15, ------------
This layout more efficiently utilizes the space in the upper right corner [ near the closet which we never requested. :-( ] and the triangular space in the lower left corner, compared to the previous version. Visitors will also be able to see over the short 026s as they enter (as it was before).

Not only that, but this new placement allows for a 30" gap between the 729s! Naturally, they could be scrunched closer together, but this seems ideal from a maintenance perspective. (I can hear Allen, Joe, and Glenn cheering ;-) There's also 30" in front of them, and all the 1401 equipment is separated by 3' (except the side-by-side 1403s).

I've also shown some proposed locations for items in the back room: the cabinet of blank punched cards, the cabinet of spare SMS cards, and the 50-Hz power converter. [ Something tells me that back room is going to be warm/hot. :-( ] I also tweaked the equipment icons to be more accurate and show the two openings in the railing.

This is a sweet layout! I think everyone can be happy with it.

- Robert

This is version ( 09 )

This version ( 11 ) includes the IBM 402 which seems likely to be available

---------- developmental dialogs ;-)) -- from Robert Sept 17, ------------
V15 floorplan features:
  1. 3 feet between 1401 units (except between the side-by-side 1403 printers).
  2. 729s are side-by-side, but grouped together per 1401 system. This plan allows for 6 feet of open space in front of the 729s, so the 729s can be rolled forward for repair/maintenance.
  3. For the "old way" of doing data processing, the 083 sorter, 513 reproducing punch, and space for the future/potential 402 accounting machine (until then, the 077 collator).
  4. Sufficient walking/elbow room in the Unit Record area (two 026s - all we have room for).
  5. In the closet, the Tape Emulator (TE) boxes, and your PC interface that punches on the 026.
  6. I suspect we'll want 4 tape drives on each system, or else we'll be eternally asked: "Why are there only 3 tape drives on one system?"

- Robert

This is version 15

------------------- status September 19, 2013 ----------------
This is a 180 degree panarama from the north wall (the exit) - distortion causes the railing nearest us to appear bent - it isn't. The burnt orange? and blue are colors sometimes used on IBM systems.
A 90 degree pan from the north-west corner. Stan has the camera. Note that the rails are straight ;-)) Ron Williams (left) is checking to see that Joe Preston and Bill Newman are doing the right thing - The cables coiled on the floor are previous power cables removed from under the floor, ready to be connected for power distribution.

------------------- status September 23, 2013 ----------------
Based on Wednesday's group discussion, here's the latest 1401 floor plan / layout:

This allows for 3 feet between the 1401 units (except the side-by-side 1403s and Unit Record equipment, which are easily moved); gives the 1402s a gap of 29" from the railing so their doors can be opened, an operator can walk in front to load/unload cards, and buttons are out of reach of a careless visitor; and has 8 feet in front of the 729s for maintenance!

This is version 16

Sept 30 - Oct 18:   Install new exhibit items


Oct 21 - 25 :   Reinstall the 1401 systems and get them working again

From Robert Garner, October 4, 2013

  • Monday, Oct 7: Professional movers will move Connecticut 1401 system and Unit Record equipment into room
  • Weds, Oct 9: Restoration team will place Unit Record and CT 1401.
  • Monday, Oct 14: Professional movers will move German 1401 system and 50 Hz converter system in room.
  • Weds, Oct 16: Restoration team will place DE 1401.
Only Stan (and Ron W) should be present on Monday Oct 7th and 14th.

---------- from Robert Garner, Oct 10, 2013 ---------------

Stan, Ron, & I had a productive session this morning adjusting the initial layout per the v16 floorplan, photos below.

Next steps: Get the DE 1401 moved in, mark the floor tile cutouts (Gary's contractor will do the cutting), reattach 1401 power & cables, bring the 1401s back up!

Thanks everyone (!) and see ya next Weds.

- Robert
CT 1401 & Unit Record equipment:
(Note: the Unit Record equipment fits best into the right entry side, which, due to closet & 6 ft walkway, is 4 feet shallower than the rest of the display area. It does accommodate three 026s.)
CT 729s: (Chic color scheme!)
CT 1401 (1403 off frame):
Space for the DE 1401 to reside: (The orange back wall is 40 feet wide.)

On Oct 14, 2013, at 8:38 AM, Karen Kroslowitz wrote:
Stan et al,

Ill have the movers here next Mon, 10/21. But I expect you or one other member of the 1401 Team there as well to help direct and answer any questions. Well start at 9am.

Karen Kroslowitz
Director of Collections
Computer History Museum

Nov 20 :   "The 1401 Experience" exhibit and demo room opens!

Team Final Push, Oct 16 -> Nov 18, 2013
Monday Wednesday Friday Saturday
Ceiling Tiles
move DE 1401
Mark Floor Tiles, Pull Tiles
Electrician - Cut Tiles, File Edges, Bezels
Start Cabling w/o Tiles
Place Tiles
(Revised to work on DE power from 50Hz converter.)
Also a little floor tile rework -
Finish Cabling, Power CT-1401
? revised to cabling the 729 tape drives ?
My pictures are on Stan's blog
Work #2
4 6 8
Work #3
11 13
Work #4
|18| Private Grand Opening |20| Grand Opening
A bit of an anti-climax after Monday, street clothes, first legal demo

Oct 23, Wednesday
German 1401 system now in place:

Oct 24, Life has been bumping along - Here is a typical report/e-mail, Stan -> Robert,
CC to the gang

Ron Williams went in today to meet with the electrician
First E-mail said the electrician would be there at 6:00AM!

Then second E-mail said 8:00 would be ok.

I replied Ron would be in around 9:00 and that seemed ok.

Ron got in around 9:00 and later an electrician came in. He was the lead.

Ron showed him what needed to be done and he said he would send down the
junior guy who was going to do the work.
FIVE hours the junior electrician came down and Ron went over the same
information again.

The junior electrician said he understood but did not have time to complete
it today.
He will do the job on Friday.


Oct 25, Here is another typical report/e-mail, Stan -> Robert,
I was in the neighborhood of the CMM today so I stopped in.

Ron Williams was in yesterday and while waiting on the electricians, 
he took all of the cables down from the Connecticut machine and 
laid them out on the floor in the direction to where they need to go. 
Thanks Ron.

All of the specified power wires are installed.
Whoever they will have to be disconnected from the IBM equipment and 
rerouted through the floor tiles. No big deal.

I turned on the 60/50 cycle power converter. It seem to work fine.

The floor tiles have been cut and returned to the room.
However, the edges of the cuts have not been finished with the 'J' trim
 to protect the cables.  
Jennifer called the contractor today and he said he would come in on 
 Monday to fix them

The corner railing has been re-installed.

I left the panel circuits to both systems turned off.

It looks like Saturday's work should go smoothly.

Oct 26, from schedule above "Start Cabling w/o Tiles "
Accomplished - LOTS - finished cabling, including unit record equipment - except for Mag Tapes :-))))
Connecticut machine reads cards, prints demo material.
Currently have problem with DE machine input power - hopefully solved Monday Oct 28th.
We think we are way ahead of schedule now !!
Present were: in order of arrival ;-)) Carl Claunch who brought friend Ian Vogelesang, Frank King, Ed Thelen, Ron Williams, and Dave Lion - all arriving before 10 AM.
Executive Summary ;-)) - Ed Thelen became exhausted watching white haired Frank King getting so much done !!
Actually, I've never seen senior citizens hustle so much - unreal - almost teenagers.

Unfortunately, I have only one picture of "cable pulling". "Cable pulling" is a bit involved because the thick (1.5 inches) cables do not bend in a tight circle such as your extension cords or PC's USB cables ;-)) Figure on a 1.5 foot radius or 3 foot diameter circle.

  1. 3 phase power comes into the 1402 (card reader/punch) then goes to the 1401 for further distribution.
    The voltages are 380 volts phase to phase, or 220 volts phases to neutral.
    We were told by ??? that the system power wiring to each 1402 is via a disconnectable plug & socket in the line.
  2. Most cables are wired into the 1401 and go from the 1401 to:
         - the 1402 card reader/punch (4 cables 2 power, 2 signal),
         - 1403 printer (3 cables, 2 look identical, but slightly different keying),
         - 1406 extra memory (3 cables)
         - 729 tape drive (2 cables) for further daizy chaining to further drives
  3. The game plan is to use excess length by going way beyond the target unit to avoid snarls of cables near the 1401. Floor tiles are moved and the cables pushed under the floor bars, making a 1 meter arc at the furthest extent.
  4. The cables go through the floor via cuts made by contractors in the floor tiles. The sharp corners of the cut must be cover with protective material to avoid cutting the covering of the cables.

First - the Connecticut 1401 system (except tapes)
Getting started "pulling cables", connecting the systems.The big pink cable ends are pink bubble wrap to protect the exposed pins in the connectors Not much romance pulling cables. Here Frank King is behind the 1406 Extended Memory and Carl Claunch is helping push the cables, one a time to Frank.
Here is Frank behind the 1406, the "cables pulled", connecting 7 SMS connectors into the backplane Proposed new cut for CT1401 tile
Cables pulled to 1402, we watch Frank hook up. "Group Picture" The system powered up just fine, but the printer chain (on 3 phase motor) ran backward. So here is Frank swaping 2 phases to make everything right :-))

Second - the German 1401 system (except tapes)
Just about the same pulling and wiring as the Connecticut machine above - until the 50Hz power problem
Quick notes: Power wouldn't come up, even utility power
Frank manually closed a particular relay, and it latched, but wouldn't pick !!
Relay voltage too low?? Quick turn off the power.
Diagram of the master power input to the system is in the 1402. Note the voltages in the added red box. We called Ron Crane, our power guru. He will meet some of us at this equipment Monday morning.
This is the top rear of Pacific Power, with voltage select switch and note This is details of the note. Since we want 370 volts phase to phase, maybe the voltage select switch should be set to 4 ??
Overview of the Pacific Power output power box This is detail of the wiring to the 1402

Oct 28, Monday - Place Tiles
(Revised to work on DE power from 50Hz converter.)
Also a little floor tile rework -
Present were Carl Claunch, Ron Crane, Robert Garner, Dave Lion, Stan Paddock, Ed Thelen and Ron Williams - Names from my "39th birthday" card ;-))
The caption was "Money can't buy happiness, But it CAN buy beer, and that's pretty damn close. Be happy on your birthday. Drink beer". So wife Betty and I went to Elephant Bar, and did ;-))
Also a little floor tile rework -
A guy who said he was the general contractor was in and out several times.
  • Could not tell us which style of protective collars would be installed
    "Depends what they deliver."
  • He wanted a date for final list of cuts and collars -
    We figured Wednesday would be a good day for that.

The "Our faces are red" Department - the 50 Hz power for the DE system -
Ron Crane, our power guru, arrived (he had previously found a serious obscure problem in the Pacific converter).
Ron said "This is not wired right, the wires should be connected to the top strip." The bottom strip is the outputs of the Class B amplifiers. (producing 131 volts RMS). The top strip is the output of the output transformers which give the switch selectable output voltages. Look here, this is the card which was in the output box. (See pictures from Saturday, above) The card gives the correct top connector wiring.
Ron corrected Pacific converter output power wiring, note use of top strip rather than the bottom strip as installed by the electrician and not corrected by "us" Saturday. Ron Crane does neat work !! Look - the utility lights are on!! Ed Thelen gets the dubious "honor" of pushing the "ON" button. Stan Paddock is covering ears, Ron Williams is cringing.

OK - Life may proceed -
Power came (and stayed) up - but the lower 4,000 characters of memory does not work. No bits, no apparent response. Here is Ron Williams, in his customary prayerful position?? trouble shooting. From Robert Garner "Yes, please post my photo too, if you could. Ron looks more professional standing vs. kneeling for mercy from the 1401 god. ;-)"
Meanwhile, Carl Claunch and Frank King are starting to cable the CT magnetic tape drives. Carl stated that after the enthusiastic activities of Saturday, he was a major buyer of over-the-counter pain killers. Here is Stan, either pulling cable for the mag tape of the DE machine, praying, or collapsing.
Carl and Stan trying to get the mag tape cables into the cut-out floor tile. I thought that computer people were white collar workers !! ?? !! ;-)) "This page intentionally left blank." ;-)) Dave Lion was mostly in the warehouse "Cyclops" hauling cables, printer paper, IBM cards, etc. and wondering where to put the rest of the office cubical of material to be removed "before the 1st".

Would you believe we *volunteered* to come back Wednesday, and continue on with this abuse ??
All this for bagels, cup cakes, and "fun" ;-))

Wednesday, Nov 13th - Notes
Time is getting "short", seven days to public grand opening.
Today 10AM - 12AM was reserved for docent practice.

You may notice some changes since last "report"

A distorted panarama of the outside.
The wall is flat, base line straight.

A distorted panarama of the inside.
The near fence is straight.

About 13 volunteers were present
George Ahearn, Carl Claunch, Bart Cotton, Bill Flora, Robert Garner, Frank King, Dave Lion, Martin Douglas, Bill Newman, Stan Paddock, Joe Preston, Ed Thelen, Ron Williams.
- Lots was happening, I should have taken notes !!

  • George Ahearn (and others) was getting set up to fix cards, found extention board, two of the SMS sockets with plugboards, related power supplies, scope for transiston curve tracing, we printed up Tim Coslet's in-circuit transistor tester.
  • Frank King was connecting tape drives, looking for cables
  • Joe Preston is out of hospital, back fixing tape drives.
  • Bill Flora and Ron Williams worked on the DE machine, ?bad memory?
  • Dave Lion mapped the floor tiles and under-floor sprinklers. Red dots rather than red tape now mark the sprinkler locations. (We are worried that moving underfloor cables will trigger a flood.) The red dots should be protected by (tough transparent tape?, clear varnish?).
  • Suddenly the door of the German 1402 would not open. Here Dave Lion and Stan Paddock are working on it. It was opened by Stan Paddock using a coat hanger - learned in his youth opening cars? with visual guidance from Dave. This is the same door on the CT 1402 - note the cable connection to the bottom latch.
  • An audio-visual person installed the components to drive the TV monitors and speakers. Testing for "feedback" to docent microphones was performed.
  • Lauren Silver from CHM came down suggesting that a transparent floor tile be made to show some of the cabling under the floor. This was regarded as a great idea, (the tough, scratch resistant LEXAN was suggested). Also, a defective cable will be available for show and tell :-))
    This is an old picture of Frank King as Hercules ;-))
  • Lots of "forward moving" activities and discussions.

Grand Opening :-)) Nov 18 -20, 2013

Nov 17, Pre-Private Grand Opening

Robert Garner (left) and Chuck Branscomb in a quite moment. Is that Jud McCarthy telling another tall tale to Jim Ingram? Scott Bellefleur (son of Buzz, unable to travel, who was the previous owner of one of the restored 1401s) having more fun. Date on plate is 1988. Scott brought a box of 1401 memorabilia, artifacts found in a closet in home.

Nov 18, Private Grand Opening, 6-9 PM
Well folks, the Private Grand Opening was the big deal!
Five of the original 1401 crew are present for a formal picture.
Chuck Branscomb, George Ahearn, Jim Ingram, Sheldon Jacobs, Jud McCarthy
Fran Underwood, the IBM 1401's architect, looking on from the monitors.

It featured a panel discussion with (left to right)
Chuck Branscomb , original 1401 project manager
    - Sheldon Jacobs, original 1401 product planning manager
    - Robert Garner, restoration 1401 project lead
    - John Hollar, Computer History Museum CEO.



Robert Garner Speaking

product planner Shel
with a word or 3 ;-)) *
Jim Ingram, original 1401 engineering manager, George Ahearn and Jud McCarthy of the original 1401 team, were in the audience.
Also present were many CHM trustees, fancy snacks and cocktails, and lots of happy spirits.
We 1401 restorers wore IBM CE clothes, ie. white shirt and tie, dark slacks, and jacket. (Wing tip shoes were optional ;-))

Robin Beresford is Robert Garner's spouse.

Chuck Presents :-))

?, ?, ?
Len Shustek
Jordan McMahon

Robin Beresford
Kirsten Tashev

Robin Beresford
Chuck Branscomb

Ron Williams
Frank King

John Hollar
Bernie Pueto
Grant Saviers
Len Shustek
Mindy Hollar

Gardner Hendrie

Carina Sweet
Valeria Alston


Bill Selmeier
Ed Thelen


Jas Lonnquist
side of Jon Plutte

Jim Strickland
Ron Williams

Sheldon Jacobs
Jim Strickland

Robin Beresford
Ed Thelen

Robin Beresford
Kate McGregor

Public Grand Opening Nov 20, 2013
A bit of an anti-climax after Monday. Today folks in street clothes
Since the German machine had troubles, the demo was on the Connecticutt machine

Grand Opening, Bill Worthington & Jim Strickland
The movie that run continuously in the Computer History Museum's 1401 Demo Lab
-- "1401: The Dawn of a New Era" --
is now available on Youtube:
- Robert
p.s. This is a revised, 2nd edition version from last November's cameo. It's 9 minutes long.

Since Grant Saviers came for the Grand Opening :-)) we had him look at a broken latch on the German 1402. I think that is rain on Stan's hat, hope so. I think the actual solution was to remove a latch from a spare ?083 sorter? which fit perfectly.

* Picture by Doug Fairbairn, more of his pictures at IBM 1401 Demo Lab Exhibit Preview.


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