Forth Meeting - at CHM
Saturday, June 24, 2006

Goal: a "quick" overview of the 1401 restoration to present -

Lecture notes, and images from web site

9:45  AM   Coffee, doughnuts, bagels on the veranda
       Please note that we need to keep the food outside the building.


     10:00 - Quick intro to era of 1401
                 big vacuum tube UNIVACs, IBM 704, 709
                 most business on card machines - work flow?
                 Transistor break through
     10:05 - 1401 physical vs card TAB rooms
               Card processing work flow - "programming"

     10:10 - 1401 - the swing machine - non-binary, very simple to program and operate, halt on error

           - 1401   characteristics
               11.5 us character memory time, 1 character at a time, instruction can be 7 characters
               800  card / minute reader, very fast and reliable!!
               250  card/minute punch
               600  line/minute printer, excellent, with beautiful output

     10:20 - Restoration efforts
              finding and procurement,  three or four "heavy hitters"
              Robert Garner, Grant Saviers, Len Shustek, Bernard Peuto, Mike Cheponis 

              They signed a contract in Euros, and by the time payment was to be made
                 the Euro went from $.88 to $1.18   :-|

The five men (above) bought the 1401 from Arnold Schweinberg who had serviced the system until it was "retired" by IBM. He obtained the system, and 1300 spare cards, and set up a little data center which he ran for some years. The system then was moved to Arnold's garage near Dortmund, Germany - where it rested and rusted until 2004.
I have worked for the IBM - Deutschland Company from 1954 to 1974 as Customer Engineer. The education for this was on 404/405/407/420/421 alpha tabulators, 602 mechanical calculator, 604 electronic calculator (tubes), 305 RAMAC (tubes), 1401/1405 DP-Systems, 1620 DP-System.
In 1963 at San Jose, California training on 1710 process control system, 360/370 Systems, and a lot of peripherals. Also specialist for IBM 1287/1288 handwriting and optical character readers. From 1974 to 1992 technical director at Data Processing Service Company. Hobbys: Construction electronics, Amateur Radio (DK3RW), HiFi, Telephone and PC, Motor Boating (new)

Arnold's notes about "our" 1401

1401 CPU, build 05/1964 working for an insurance company till 1972, after that moved to Arnoldīs Data Processing Center (Newspapers and Magazines)until 1977, then stored in a warehouse and sometimes displayed on exhibitions. The last show was in the lobby at the IBM Branch Office at Dortmund, Germany
paper work - CHM proposal, plan, Home with raised floor - just like the best old days room was server farm, still has two large air conditioners and an un-interruptable power supply




1401 Operators Panel
CHM meetings is early 2004 transportation from Germany - IBM Almadin - this time the artifact cost more than the transportation a warm dry home, security, access, white gloves gathering people - IBM Quarter Century Club June 2004 Robert Garner's Current Status Report Action Groups, leaders, plans for restoration of subsystem, info about subsystem 1401 Processor w/ 1406 added memory, 1402 Card Reader/Punch, 1403 Printer 729 Tape Units, Software We decided to work every Wednesday - and the 2nd and 4th Saturdays. After about a year, the tape guys came in on Thursdays to stay out of the hair of the processor guys My role is town crier (web site), day-to-day museum interface, Xerox operator extraordinaire, power supply checkout, and head janitor ;-)) Machine runs at European standard 50 Hz (cycles/second) Should we convert U.S. 60 hz to machine 50 hz power - or convert machines to 60 hz ? if 50 hz, motor generator or static All power (except motors) is run through ferroresonant regulators 10 to 1 regulation at full load, better at no load All DC power supplies are linear - with pass transistors We decided (after much soul searching) to keep the machine at 50 hz and use a static (solid state) frequency converter. August 2004 - free 5 Kw converter from IBM


w Dave Bennet

Power Monitor

Elgar 1750

side view
- 1st system - 5 KW - the meaning of marginal like plugging in a vacuum tube scope to the 50 hz utility outlet would trip the circuit breakers - and they would trip anyway intermittently - 2nd system - 18 KW - steady as a rock both use class B amplifiers - 50% theoretical - if rail-to-rail
April 6th 2005 - Founder of the Feast !! This Pacific Power 390G 50 Hz supply has more than three times the power of the previous Elgar. The 1401, 1402, 1403 and 1406 running concurrently uses about half of its capability :-)) Previously only one unit at a time could be usefully on, and we couldn't even start the 1403 printer motor.
Ed Thelen is glowing, and the 50 Hz converter is cool ;-))
documentation - ALDs, ... printed by a specially chained printer - sideways :-))
Left: A "typical" clean Automated Logic Diagram (ALD) - on 11" x 17" sheet of paper
Right: Top of that page
special problems - - in the early days of transistor computers, the salesmen talked up "Solid State Reliability" - oh yeah - We all took a 2 hour course in artifact handling - acid from skin etching metal - oil and acid degrading paper - wash hands and wear gloves - electrolytic capacitors PDP-1 philosophy - fancy equipment running a script our philosophy - series 4 watt bulb findings
Don Cull reforming/checking capacitors. August 25, 2004
LaFarr Stuart is trying to con Milt Thomas that this is on the up&up.
F.E. revolt - no white gloves while struggling with our greasy, grimy physical reality. It is a "don't ask, don't tell" situation. Arnold Schweinsberg seemed to expect it to turn-on and go, he wanted to be here for a week to make sure we did it right. We thought it best if we did some early preparations first, and bringt him over for a few weeks if/when we had trouble. The system has been powered on for over 670 hours, (IBM machine clock) and about 900 person-sessions of direct and indirect (me) labor applied, and we are just now starting to successfully run the diagnostic deck - about three decks out of maybe 50. It is reasonable to ask "when will you be done?" - people have been asking for two years now - We have not reached the point of "REAL SOON NOW". 1401 corrosion, replacements, diodes, transistors - even 56 microhenry inductors open ( like at least 8 so far) - germanium diodes with iron leads - corrosion along leads broke glass maybe another 30 - degraded gain in transistors - again maybe 30 - grossly corroded transistor leads - open - maybe 10

It is a little alarming that so many passive components (inductors, basically a coil of wire in plastic) and simple diodes fail. (In the glass diodes, corrosion seems to creep along the wire to glass contact, expanding and cracking the glass, and the diode fails by some mechanism.) To date we have replaced maybe 30 diodes and 10 inductors? Scary. cooling fans powerup sequencing relays card debug tools Tim Coslet's in-circuit testor Scope plug in -------------- the following are "typical" daily reports from the web site ----------------- The goal is to give a flavor for what we have been doing these past two years. Included are the many support functions such as: Sorting, inventoring, storing 1,300 spare logic cards, clean the crud and grime from 25 years of usage and 25 years storage, repair and make unavailable parts, refurbishing worn/corroded parts, fighting insufficient power, cabinets to house spares, documenting logic cards, copying diagnostic decks, accumulating parts from generous doners and e-bay, software emulation, ... and ...
  • Saturday December 11th 2004 - 9:30 AM - second Saturday - Pizza :-))
    Present were: Allen Palmer, Tim Coslett, Bob Erickson, Ron Williams, Robert Garner, Ed Thelen. More discoveries on the power situation. The main contactor in the 1402 needs 50 Hz, during bring up it was on a 60 Hz temporary circuit and did not close reliably. The power supply in the 1st 729 tape unit has been re-installed after checking capacitors and performance. The glitch in one phase is still present. Wiring schematics for 1403 have not been found. October 2004
    Tim Coslet, Ron Williams, and Bob Erickson chasing a clock pulse problem. Note the use of "IBM Blue" "pulpit" that Ron Williams made. ;-))
    Jan 2005
    Jan 22nd - Tim Coslet working on "our" 026 keypunch. A fuse had opened every time the keypunch was turned on. The capacitor at the end of the red arrow has just been reformed by placing it in series with a 4 watt 120 volt night light. The night light glowed hotly for about a minute then slowly dimmed to a dull orange glow. The newly reformed capacitor is working well, the fuse no longer blows. Tim is inserting another 25L6 tube that had been cannibalized.
    Jan 22nd - Bob Erickson (left) and Ron Williams trouble shooting the 1401. Allen Palmer's oscilloscope is a vintage vacuum tube Tektronix :-) used to troubleshoot 1401s in its former active life. The brown unit in the left background is the overworked Elgar unit making the 50 Hz used by both the 1401 and the scope. Ron made the blue pulpit (and low roller chairs and other things) to make life easier.
    Jan 22nd - Ron Williams (left) and Bob Erickson trouble shooting the 1401. One "gate" of the 1401 is swung out for access to wiring side and wire wrap pins. Ron is looking at a copy of the ALD (Automated Logic Diagram) which was printed many years ago by a 1403 with a special chain.
    Feb 2005

    Allen 729 Terms

    729 Mechanicals

    077 Naked

    3-48 shoulder Screw

    Glenn Ed JToole
    April 13 - A truly beautiful day, lotsa power, lotsa folks, lotsa progress, lotsa fun :-))

    Allen & Grant

    Busy Busy

    Allen & Frank Loading 729

    Chuck & Don

    Allen Running 729
    As Jackie Gleason used to say "How sweet it is!!"

    3 new voltmeters :-))

    Tim, bad circuit

    Tim, good circuit

    Tim - Pensive,
    what is this thing trying to tell me?

    Ron at the console
    August 24th, 2005

    removing clutch

    dynamic timer circuit

    Ron F. thinking

    4to11k stack

    not memory cores
    October 19th 2005
    The 1402 Reader timing "Circuit Breakers", CBs have been cleaned and adjusted, the read brushes checked, the card path transport works, two broken wires found and repaired, relays checked, timing light struggled with, belts replaced, bearings checked and lubricated, on and on, ...
    In the 1401 processor, the multiple power supplies checked and working, some 70 faults in the 1401, including about 50 cards have been replaced/fixed, the clocks and lower memory works, instruction fetch and execute cycles work, about half of the instructions work when manually inserted via switches, ... .
    And at long last, the card reader and processor work well enough to read and execute the first two diagnostic decks :-))
    Here are the 1402 Reader/Punch and 1401 Processor team members present at First Light :-))
    And the original Diagnostic (and other decks) were read in using a borrowed card reader to CD ROM and other storage. Diagnostic deck information Here are the Diagnostic Decks that still yet to be performed correctly. Note that decks one and two are missing - the machine read in and performed these two tests correctly :-))
    A 28 megabyte .avi file Here is a 30 second movie of the first attempt to read a large deck (of blank cards) into the 1401 via the card reader - note that there is work yet to be done ;-|
    Punched card diagnostics October 26th 2005
    The clutch assembly (right reel) on the 729. The slip rings can be seen. The left two clutches are the tape up and tape down w.r.t. the columns and the front geared clutch is the brake and load/unload clutch.
    The left reel assembly with the series wound motor used for high speed rewind. The other clutch functions are the same as 00249
    Allen Palmer with version 1 of the torque measuring setup to test IBM vs Placid clutch powders.
    Rev 2 of the powder torque vs current setup. Chatillon force gauges are connected to the aluminum swing arm to apply a calibrated force at three different radii. The DVM measures the coil current.
    Grant Saviers using the hand press to make new internal felt seal washers with the dies designed for this purpose
    The .xls spread sheet "clutch powder" and chart shows the measured torque values for different clutch powders and different amounts of the Placid powder. 20gms of Placid powder was selected as the best amount.
    The .xls spread sheet "bearing deflections" shows the angular displacement vs load for three (none, one and two) 0.0039" shims between the two radial ball bearings to provide preload. The original MRC duplex bearing was also measured. As a result a compromise shim value of 0.006" will be used in the final assembly.
    Many ALDs very hard to read, even with bi-focals and magnifying glass we have a CDROM of related ALDs from Australia :-)) 1402 Reader/punch belts timing circuit and display rust - replace card path CBs - timing punch dies need cleaning? 1403 Printer binding slugs lubrication backward cooling fan December 28, 2005
  • Frank & Bill replaced (soldered in) an open fuse to a printer driver card. The fuse in the other defective card seems OK.
  • We got extra printer driver cards from the 1401 in Visible Storage - they were a different part number on the same part number card - a wire on one version was replaced by a resistor in the other version - they seem interchangeable.
  • This is the back side of the printer hammer assembly. The black air hose is from a fan used to cool the parts and blow paper dust out of the area.
  • The German 1403 did not have "support rails" - so we got the rails from the unit in Visible Storage and removed the printer hammer assembly. This helps support the heavy assembly during rather delacate operations.
  • This image is very confusing - you are looking at the BACK of the paper from the hammer side. This side is normally white - but got printed and reversed to save paper. - Sorry - So, you see the Hammer Assembly on the left, supported by the rails. The paper tractors on each side of the paper, and the hammer view of the paper to be printed - the ink is deposited on THE OTHER side of the paper.
  • Frank King is holding a tool which has a central shaft with an excentric head. It is used to adjust print hammers.
  • There is/was a 0.003 inch, thick 18 inch long, 0.500 inches wide ?mylar? flexible plastic ribbon associated with the print head assembly that had ?decomposed?? and was removed by vaccuuming. We need another inorder (lets get an 8 foot section?) to get the print hammer assembly correctly reassembled.
  • So - I guess the printer no longer prints :-(( Pending replacement of this needed 1960s era item - probably no longer obtainable from IBM - 1406 Extended Memory visible broken wire in core memory While we were not there, a building maintenance person wanted to change some ceiling lamps, and found it useful to move the already cabled 1406 around a bit. Sharp edges in the 1406 frame cut into the insulation of the signal wires causing multiple shorts and opens. The shorts took out a few more cards in the 1401. 729 Magnetic tape drives rubber belts rubber capstains relays lights & photo cells rust/corrosion on V-Belt drives on clutches clutch brushes V-belts squeeking magnet coil assembled backward felt washers to retain magnetic powder new magnetic powder mangled tiny screw 077 Collator bearings open coils drive belt 083 Sorter CBs bearings belts rust drive design 026 Key Punch initial blowing fuses - 250 volt electrolytic hard rubber - poor registration, jamms print head - varnish/oil? - alignment Spare SMS cards May 2006
    Grant Saviers brought in some more tools, and 100 more separators for the SMS drawers. He arranged tools in the main tool chest, and made/placed labels.

  • Ed Thelen and Chuck Kantmann continued making labeling SMS drawer separators, and taking the unsorted SMS cards from the various boxes and sorting them into the SMS drawers. There are some types of SMS cards We have a large number (say 30+) of some types of SMS cards. As there will not be enough room in the 4 large SMS drawers for all the cards, some of the surplus cards are being returned to now partitioned and labeled boxes.

  • Chuck Kantmann and Ed Thelen completed labeling, and filling the four new drawers with SMS cards. Chuck Kantmann and Ed Thelen (with Ron Williams our customer observing intently) completed a count/inventory of the SMS cards in the four drawers and overflow boxes.

    And yes - the drawers are a little out of sequence :-(( After filling the drawers we discovered the bottom four drawers were *not* the same size. - When life is less pressing, we may swap the contents and labels of two drawers.

  • The overflow boxes with new white labels reflecting contents :-))
    10:45 - demo ROPE - Ron Mak?? 11:00 tour the 1401 restoration effort, demo - maybe better here than after indefinite length lunch? My role is "step and fetch it", and a major interface to CHM support facilities - power, light, air conditioning - help get permission and "fetch" parts from - commercial vendors - CHM Visible (and invisible) Storage - wear out Xerox machines for working copies of ALDs and manuals - floor sweeping and trash hauling and other faceless activities. ---- images shown ----------- ---- handouts, duplicat images? ------------ 11:15 AM WELCOME TO THE CHM --- Jim Somers, CHM Volunteer Coordinator The CHM needs your donations of artifacts, wisdom, and cash. You can help out as a docent, with restoration, or as a Geeter. 11:30 AM IBM 350 RAMAC (vintage 1958) IN BRIEF --- Ed Thelen A short overview of the first random access magnetic disk.
    a) IBM's RAMAC 350, the world's first Random Access Magnetic Disk Drive
    the ancestor of the hard drive in your computer.
    b) The restoration of the storage section of one of these machines.

    image from the IBM Archives
    "Our" RAMAC. on loan from IBM
    image from the Magnetic Disk Heritage Center

    RAMAC characteristics

    Why a disk vs drum 99 Notre Dame Santa Clara, physical Santa Clara, drive servo CHM ---- images shown ----------- -------- handouts, duplicat images? ------------ IBM-227-3534-0-RAMAC-305-350-pgs-62-98.pdf pages 63-67 Control Overview
    • The upper left tapped pot shows the track (horizontal) setpoint and position feedback.
    • The arm bearing the read write erase head(s) is upper right, showing a disk detent to prevent vertical movement while arm is carrying heads onto selected disk.
    • The lower left tapped pot shows the disk (vertical) setpoint and position feedback
    • The servo/clutch Amplifier, motion select clutches, tach, and drive capstain (for both vertical & horizontal) is lower right
    11:45 - tour of RAMAC? or after lunch?? 12:00 Lunch - Togo's across the street 1:00 TOURS * IBM 1401 * Maybe RAMAC Restorations * Not to mention Visible Storage, where all your old friends live.