Schedule September 2009

return to main 1401 Restoration Page
go to Team Bios

Wed September 2 - General, Thurs September 3 - Tape Team,
Wed September 9 - General, Thurs September 10 - Tape Team, Sat September 12 - 2nd Sat
Wed September 16 - General, Thurs September 17 - Tape Team,
Wed September 23 - General, Thurs September 24 - Tape Team, Sat September 26 - 4th Sat
Wed September 30 - General,

Wed September 02 - general

  • Present were: Ron Williams, Bob Erickson, Bill Flora, Frank King, Joe Preston, Don Luke, Stan Paddock, Bill Newman, Ron Crane, George Ahearn, Ed Thelen, Robert Garner. We had about 25 guests total.

  • Bill Flora, who knows no fear, decided to get the margining power supply (located in the 1402) fixed for the CT 1401. Since I am the "power supply guy" I got involved, things were not going well (the remote controls?) so Bill Newman and Ron Williams got dragged into the fray - and we all learned more about voltage margining. But not enough because the margining system is not working yet -
    This oil filled 6 microfarad 330 v ac capacitor blew some months ago and has long since been replaced. It was used in the circuit of the ferroresonant voltage regulating transformer.
    This is the front of the Margin Remote Control in the CT1401. Note you can either increase (boost) or decrease (buck) the controlled power supply voltage. The back side of the panel to the left This telephone type plug selects which marginal voltage to adjust with the Remote Control. The top socket in the red bakelite is "REST", does nothing.

  • Bob Erickson worked on aligning the 513 reproducing punch after taking it apart to get the oil pump fixed - did I mention that Stan Paddock said that he fixes oil pumps of antique cars with 5 mill teflon sheets- we are trying this fix here.

    In any case, Bob got to counting funny, like he didn't have no schoolin or nothin -
    12, 11, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 13, 14, then back to 12 again !!

    He explained that the marks on the main timing gear are in the same order as the card rows going through the machine - starting at the 12 edge first, and that the 13 and 14 are the spacings between the rows of adjacent cards going through the machine.

    and there are two clutches that have to lock up, one at 13.5 (five teeth after 13) and 14.1 (one tooth after 14)

    Ya know, those people that designed those machines had to be pretty clever!!
    Complicated - OH MY

  • This is embarrasing, the folks were busy, Joe Preston and Don Luke polishing the 729 mag tape hubs - standing tall - and there were many activities I missed completely :-((

  • Stan brought in some JAVA experts who he hopes to con into making some enhancements to Ron Mak's ROPE. Ron Crane brought in some friends

  • And George Ahearn had some guest from ProofPoint Inc.
    What a fun day :-))

Thursday September 03 - Tape Team

Wednesday September 9 - General

Thursday September 10 - Tape Team

Saturday September 12 - 2nd Saturday

Wednesday September 16 - General

  • Present were: Ron Williams, Bob Erickson, Bill Flora, Frank King, Glenn lea, Joe Preston, Don Luke, Stan Paddock, Bill Newman, George Ahearn, Jim Hunt, Ed Thelen.
    Robert Garner is on sabbatical - something about visiting WWAM principal Maurice Papo in France, and other activities. (He has been e-mailing from Rome ;-))

  • Jim Hunt is back from Burning Man. He said that he is browned - to me it looks like a bad sun burn. Jim says that there is more going on than the rumored lack of conventional inhibitions. He says to search on 'Big Rig Jig', 'Temple of Gravity', 'Burning Man Colossus', 'Burning Man Wave Waffle', 'Burning Man Uchronia'.
    After getting de-briefed in detail by Ed Thelen ;-)) Jim got down (or up) to fixing SMS cards again :-))

  • We are starting to print more on the CT 1403. Frank King is unhappy with the print quality/alignment. So - alignment time is coming -

  • More action on CT Margin Checking. Last week, we used two resistors to emulate the pot in the Remote Margin Control. The circuit breaker opened each time we tried to power up the unit. During the intervening week, Bill Newman found that you really need a pot, and it must be at 0 when applying power. Now we can boost the margin voltage, but not buck it. More study !!
    Boosting the +6 volt margin by 1 volt (up to 3 volts is allowable) caused dramatic failures - the printer went into high speed slew, and almost all the lights on the operator panel lit, including all peripheral error lights and all the register select lamps (only one on at a time is normal operation). Looked like a lamp test.
    The computer resumed normal operation after we removed the Margin Boost, and pushed most of the RESET buttons. Whew!! :-| :-)) Presumably many marginal circuits? You are supposed to be able to run system diagnostics successfully when the margins are both boosted and bucked -
    Apparently the 1401 does not have a good single "check everything test" to run while varying the margins. Apparently a test called "Midas" was developed for the System 360 to exercize the system while margin testing. Bill Flora says that on the SAGE system, diagnostic software could actually vary the margin voltages - no human intervention required.

  • Glenn Lea and Bob Erickson working on the 077 collator.

  • Bill Newman started trying to place the output of ROPE assembler onto the pseudo tape that Bob Feretich built. The goal was to then load the pseudo tape into the 1401 and run the code :-))
    To avoid "illegal character" warnings, you must select "Pierce IBM A" encoding! Also, the 1401 loads/boots/IPLs from TAPE 1 only. The code got into the 1401 correctly !! :-))))

  • Len Shustek, 2nd from right, CHM Chairman of the Board, brought two friends, shown talking with Frank King.
    Len says "They are George and Barbara Keremedjiev, the proprietors of the second-best computer museum in the US, the American Computer Museum in Boseman Montana. See Definitely worth a visit when you are next in the vicinity of Yellowstone."

  • Joe Preston and Glenn Lea were cleaning contacts in one of the 729 tape drives. Something about contact files wearing out, something about getting the wife's emery boards, for fingernails, and for relay contacts? I think I used to hear complaints that the abrasive particles from emery boards could get stuck between contacts??? -

  • In 2002, Bob Erickson made this little binary adder. No logic elements other than diodes to prevent "back currents"
    This is the logic of each binary digit switch This is the overall logic
    Bob said that working on the 1401 systems has saved him from further projects like this ;-))

Thursday September 17 - Tape Team

Wednesday September 23 - General

Thursday September 24 - Tape Team

Saturday September 26 - 4th Saturday

Wednesday September 30 - General

Go to
October 2009
go to Team Bios