Schedule August 2009

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Wed August 5 - General, Thurs August 6 - Tape Team, Sat August 8 - 2nd Sat
Wed August 12 - General, Thurs August 13 - Tape Team,
Wed August 19 - General, Thurs August 20 - Tape Team, Sat August 22 - 4th Sat
Wed August 26 - General, Thurs August 27 - Tape Team, Sat August 29

Wed August 05 - general

Thursday August 06 - Tape Team

Saturday August 08 - 2nd Saturday

Wednesday August 12 - General

  • Present were: Ron Williams, Bob Erickson, Bill Flora, Allen Palmer, Joe Preston, Don Luke, Stan Paddock, Bill Newman, Jim Hunt, Ed Thelen, Robert Garner.
    We demoed for 7 people.

  • Lyle Bickly showed some friends from Beijing our 1401s. The man on the left is a UNIX guru and had worked with Lyle in the 1980s. The lady with her hands on the rail had programmed a 1401 in Beijing some years ago.

  • Robert Garner introducing Shel Jacobs, 1401 product planner and 1401 champion.
    Shel talking. Not shown clearly is Shel's 1954 100% Quota Club Tie Pin.

  • Jim Hunt fixed 6 more cards. Of course obtaining replacement transistors is "interesting". The 1401 is full of germanium "alloy" style transistors - obsolete for some years. We are beginning to substitute using silicon transistors, acceptable because of the wide voltage swings.

  • But sometimes even the case styles are different, this looks like a modified T-03 case style. Steve Russel, of PDP-1 restoration, came by and was drafted into consulting what to do about this bad switch core driver transistor - Bill Newman is investigating further -

  • Here Joe Preston (left) and Bill Flora are chasing/wrestling with a switch problem. When removed, the switch had variable closed resistance up to 60 ohms. Jim Hunt came by with "Switches are bitches."

  • Allen Palmer showed off this newspaper of "Life Was Interesting days" when Intel and Microsoft were not dominant ;-))

  • Steve Paddock showed off his multiple tape demo program. A switch selectable number of tapes are written with random numbers of tape records - looks (and sounds) as though some serious work is being done ;-))

  • The above is not a complete list of happenings - but ya gets what ya pays for -

NOTE: Brown Bag Lunch - 12:00

IBM 1401 team member Shel Jacobs will be giving a special talk about the history of the 1401 planning and announcement efforts at the Computer History Museum, Weds, Aug 12th, noon, at the Museum volunteer's brown bag luncheon.

Here is Shel's abstract for the talk.  Even though this impassioned work happened 50 years ago, Shel has a remarkable and inimitable memory for details, especially entertaining ones.  (This is an extended version of the talk he gave to the 1401 restoration team last year.  We will record it.  Please do NOT "reply all" to this email, thx!)



What was a transplant from marketing, with a degree in accounting, doing in the Glendale Lab?
This talk will cover some of the non-engineering efforts that took place to support the 1401. It has been referred to as Marketing. It has been called Sales. Neither of these is accurate.  It should more properly be called Planning.
Planning included a wide variety of activities:
1)      Market planning looked at the customer’s environment.
        What were they doing?
        What did they want in future products?
Initial efforts were visits to customer installations to identify complex applications as tests for the early 1401 designs. Subsequent meeting were held representatives of the field operations, customer education, sales, customer engineering, systems engineering, to get their reactions to the 1401 specifications. A final round of meetings with held with simulated customer classes made up of representatives from operating installations within IBM.
2)      Product planning worked with engineering in matching customer desires with engineering capabilities.
Activities addresses multiply/divide alternatives, printer models, creating a
1401-D for offline tape to printer, and the adequacy and use of the memory.
3)      Business planning required putting together the data to demonstrate financially viable projections.
Activities included competitive analysis, establishing price targets, reviewing the installed product base to establish acceptance levels in developing acceptance estimates.
Considerable effort was focused on overcoming perceived shortcomings that would restrict customer orders. Getting an announcement level forecast that would support the target prices was pivotal in getting announcement approval.
4)      Sales release planning addressed efforts to announce and explain the system to the sales force and our customers.
An aggressive marketing support program was put into place. Early prototypes and mockups were used in filming a nationwide TV introduction. Print samples were prepared to illustrate the quality of the new 1403 printer. Application brochures were prepared using field case study material. Extensive efforts took place with an outside promotional company to prepare marketing brochures and advertising copy.
We will cover the iterations and interactions with the IBM field and staff groups to satisfy the various checks and balances within the IBM Corporation leading to the big day---

October 5, 1959 – the 1401 Announcement



- Robert

IBM Almaden Research Center, San Jose, CA
Office:  408-927-1739
Mobile: 408-679-0976

Thursday August 13 - Tape Team

Wednesday August 19 - General

Thursday August 20 - Tape Team

Saturday August 22 - 4th Saturday

Wednesday August 26 - General

  • Present were: Ron Williams, Bob Erickson, Frank King, Joe Preston, Don Luke, Sam Sjogren, Bill Newman, George Ahearn, Ed Thelen, Robert Garner. We had 8 visitors two docents brought around.

  • Santa arrived - well, transistors Robert Garner got from e-bay, :-)) and a big box of plugboard jumpers for a 403 or 407 type accounting machine :-))
    Glen playing Santa 403 Type Jumpers
    2N1302 - PNP transistors. We now have lots :-)) 2N1305 - NPN transistors Isn't that just too sweet for words?

  • A no costume day with a professional photographer and assistant
    The classic photographer shoots photographer Robert & Ron as Models A view of the image on the PC

  • All during the above EXTENDED uproar, lots of pictures, many subjects, Joe and Glen worked on getting the window on the door of a 729 to work properly. Springy cables on spring driven drums require superior coordination :-|

  • The photographers finally left - our smile muscles were fatigued and painful. At last we could turn on the equipment, and frown and snarl as normal ;-))
    Ron Williams, George Ahearn and Bill Newman decided to try to fix the problem in the adder of the CT machine - something about failing to re-complement after a subtract if the larger value was in the a address, or was it the b - I forget.
    There are several methods of trouble shooting - one possibility if you have two machines, with only one bad - is to compare signals - this method might require little thinking :-))
    So, Ron Williams set up a program loop with appropriate data into both the DE (German) and CT (Connecticut) machines, and we could start comparative scoping
    George placing a probe in the adder of the CT machine Hmmm, what have we got ??
    Hmmm. this machine doesn't seem like that machine ??!!??
    Is this the bug??

    Curses !! The machines are not identical -

    a) one machine a 1962 revision level, the other a 1963
    b) one machine had the British Sterling option - really messing with the adder :-((
    Probably have to get analytical, brain strain !! :-(((
    Time to go home, another day -

  • Robert also brought a core plane, was it for the 1401? No - look how tiny the cores are !! must be much later (and faster). The diode leads are 0.020 inch diameter. Do you figure those cores have an outside diameter of 0.020 inch? Note the three wire system - no sense wire zigzaged to reduce half select noise :-|

Thursday August 27 - Tape Team

From Bob Feretich
Debug status of the CT 1401 -- 8-27-09 (Allen & I working that day)
  • Fixed Complement Add/Subtract bug. An ALU Carry trigger was very slow. The carry bit would not initialize to 1 at the end of the "reverse scan" when running at speed. It seemed to initialize OK sometimes when running single cycle, but the failure in Run mode was consistent. I replaced the trigger card.
  • I booted the CPU diagnostic test suite tape. Enabled the optional CPU diagnostics (indexing, modify address. etc.) Ran the test suite. The CT 1401 now runs all the CPU diagnostics we have cleanly. The above card replacement also seems to have fixed the Zone Add bug.
  • The CPU Diagnostic Test Suite tape image is available in the 729 Tape Drive Emulator's library.
  • Sam is working on a Reader/Punch/Printer Diagnostic Test Suite tape image and a 729 Tape Drive Diagnostic Test Suite tape image. We will place them in the library after we have verified them.
  • There are several diagnostic tests that are missing from our suite. For example, we don't have any Multiply, Divide, or memory tests. If anyone can obtain them, we can add them to the test suite.
Neither Sam nor I will be in next week. We plan to be back in two weeks.

Bob Feretich

Robert Garner responded

Bob,  Sam, et al,
The CT 1401 now runs all the CPU diagnostics we have cleanly.
You guys are incredible  - great work!!!!!

For cc'ers - The diagnostic tape image was uploaded into the CT 1401  
via the 729 Emulator box (from a file in the PC).
Pics of the 729 Emulator:

- Robert

Saturday August 29
from Stan Paddock
Great news on fixing the CT Complement Add/Subtract bug.

However, that bug is not what stopped the 1402 from reading cards.

Ron Williams and Bob Erickson worked on it today and Bob found a loose connection. The reader now works fine.

I ran my tape demonstration tape program on the CT machine and part way into the program, we get a memory error. The program works fine on the German machine. Have to look into this.

We had quite a few guests in today. Some in the scheduled group and many people who just stopped by.

Number 4 keypunch is down. It looks like it tossed it's belt. Will fix it next week.


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