Schedule July 2008
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Contents:
Wed July 2 - General
Wed July 09 - general
Sat July 12 - CHM Volunteer Work Day
Wed July 16 - General
Wed July 23 - general
Tim was hospitalized
about a week ago (not the first time) and figures he will never be employed again. Judith Haemmerle has treated Tim like family,
helping clean his apartment, caring for his cats, settle accounts, get his (?COBRA?) medical insurance transferred for
service in Montana, packing Tim's items for the journey, ...
Thursday, Tim's brother will start driving Tim back to his family in Montana -
So "we" decided to save time and the technical risk of removing and replacing equipment and wiring -
by just powering up the 1st CT 729 Mod 2 tape drive. We applied power, and no dynamics :-))
The voltages seemed reasonable, but the voltages did not appear on the power supply terminal strips
in the same positions as shown on the schematics for that drive :-| Much casting about for why the
mis-match.
Sat July 26 - CHM Volunteer Work Day
A test loop of multiple Clear Storage instructions works fine
in single step, but not in Run mode (existing problem).
We traced
that bug for a while on the storage scope (triggering on the error
check), narrowing the problem down to several candidate gates. As it
was after 4 pm, and we had places to be, time to stop. We should have
it licked next session! ;-)
Wed July 30 - general
Now to put the chain on the two pulleys, with the "9" slug at the correct index point on one of the pulleys.
Wed July 02 - general,
Wed July 9 - general,
Sat July 12 - CHM Volunteer Work Day,
Wed July 16 - general,
Wed July 23 - general,
Sat July 26 - CHM Volunteer Work Day,
Wed July 30 - general,
from Stan Paddock, Tuesday
Daily Reports, Team Bios and Current Status Report (March 2008 ), Proposal to Acquire & Restore the "Connecticut 1401
Robert Garner says
I just spoke with Dennis Cassar.
Remember: Ron is assuming that us "younger" engineers (i.e, you, Ron Crane, Bob Feretich, and I) will
bring up the 1401 this time. We're in for it.... ;-)
It was apparent that someone was catagorizing some of the CT spare cards.
Judith seemed to deflect questions -
Allen Palmer has just "cleaned" the badly pitted contacts on this 729 column sense (bellows) switch -
and is re-adjusting it.
I was out on some kind of raid into the museum.
Chris Garcia called out that he had something to show me.
I identified it as a 2 gun electrostatic deflection CRT -
and figured that Bob Erickson (who serviced Williams Tube memories on the
IBM 701) would get a kick out of it. Would you go for a DuMont 5SP7 which is used
in a Tektronics 555?
Bob Erickson's grandson "JD" (right) came in with a friend. We gave them a "special" tour,
including a comprehensive tour of "Visible Storage" :-)) JD isn't embarrased,
he is working on a golf course ;-))
Frank King struggling to connect very stiff cable to 1403 printer
and another on the other side - these contain the hammer driver currents from the controller in the 1401
The power cable will be installed in the center after CPU successful power up.
A BIG day :-)) - Power up on Connecticut system :-)) Lunch at GOOGLE ;-))
While working with the 1402 belts, Bill Flora notice that the belt that enables the card punch to delivers
cards into the center pocket was missing, and another broke with only slight stress. So - do we have belts?
Lots, lets hope the correct ones :-))
OK - lets start at the wall panel. The bottom three ganged breakers are for the German 1401 - They need to
be rated at 90 amps because of the inefficiencies in the 60 Hz to 50 Hz power convert.
Just above are the new three ganged (if one trips, all trip) 60 amp circuit breakers for the Connecticut system installed
by the electrician ( the normal circuit for an IBM 1401 with tapes. )
The cable from the wall panel terminates in the right angle socket sitting on the underfloor. The cable from the
1401 Card Reader/Punch (the main power connection for the 1401 system) is sitting on the raised floor. Husky looking
hardware eh?
Excitement, Ron's lit utility lamp indicates the 1401 now has utility power, like to plug in oscilloscopes -
but the rest of the power did not come up. :-| We are scrambling about looking for blown fuzzes, open interlocks,
anything ... I hear that Bill Flora leaned on some relay and 48 volt relay power came up and stayed up -
dirt in contacts??
How is this for a hopeful look on Robert Garner? 48 volt relay power is up, and the push buttons ready
to trigger the power up sequence relays.
Well - the power came up briefly, but a -12 volt power supply tripped :-(( What to do? Think, Think -
Well, nothing smoked, lets try again, and this time power came up and stayed up :-)))))
Well, at least we have a clock -
Now that the machine is alive once more - here is the running time meter :-|
Unfortunately, the 1401 is not working correctly yet - a fetch from memory yields all bits on regardless
of what you think you put in. :-(( Work to do - maybe much work -
Shortly thereafter, Glenn and Stan started moving the least good looking (decomposed rubber) 729 mod 2 tape units
to invisible storage. Life is so much sweeter when you have proper moving equipment :-))
Frank is REALLY eager to get his 1403 printer going - all the shafts rotate, there is sufficient hydraulic
fluid and other fluids - Lets get this baby going!! He started out by disabling the 60 volts to the hammer drivers
in case there is a problem in the printer driver clock circuit. Too long a pulse to the hammers can blow out
soldered-in fuses in groups of 20 - no fun!!
1403 motors going in the correct direction - we assured correct phasing way back in the 1402, above - But a
very worrisome racket!! Very noticeable!! Here is Frank using a large screwdriver as a stethoscope,
trying to determine the source of the racket.
The noise seemed to be coming from the output shaft of the 1/3 horsepower 3 phase motor driving the
hydraulic "transmission".
Frank called in Bob Erickson for a second opinion -
The racket slowly subsided, and after about 10 minutes, the machine almost sounded normal :-))
Of course, we haven't put a print chain in yet -
About then, John Hollar<, (white shirt),
the new CEO of Computer History Museum appeared, with Paula Jabloner, Karen Kroslowitz, and
By then, it was past our appointed time (12:45) for a lunch at GOOGLE, arranged by Judith - but Robert wanted to get
a nice group picture of us - It seemed to take for ever to set up the tripod, ..., and all of the usual delays
- but the result, at long hungry last, was very nice,
allowing for the subject matter and fatigue factor ;-))
And off to GOOGLE
Judith says our host, Marcin Wichary, is a young CHM Docent and avid photographer (took the best images of the Babbage Machine at
CHM by waiting for night - no outside light distractions).
Wouldn't you just know - I didn't get a good image of Marcin.
We had a GREAT lunch - I started out with three desserts and some cookies ;-)) Then a tour of
GOOGLE, now in the last headquarters of Silicon Graphics. A classic boom, build fancy headquarters, and bust -
GREAT tour Marcin, thanks much.
After the tour, including many little food places - Marcin says GOOGLE wants free food near all employees -
a laundromat, and interesting hallways - here is a mock-up of
Space Ship 1 winner of the X-Prize.
Marcin returned us to a Slurpy bar, where we topped-off our food reserves.
and had a great view of T-Rex ;-))
Stan Paddock
Report from Stan Paddock.
[Ed Thelen was AWOL, attending a memorial service.]
When we get the lower memory to work right, we can start trying the 1402 and
1403. Exciting.
After hours, I went to visit Tim Coslet at Sequoia Hospital in Redwood City. Tim had kind of fallen apart, seriously, and
Judith had taken him to Kaiser, then to Sequoia on Monday. Tim said that Mike Cheponis had visited him Tuesday.
I had to wait half an hour after visiting hours opened Wednesday because "Sandy" and another ex-coworker from
WatkinsJohnson got in ahead of me. Tim and I talked of many things until visiting hours closed, and I was asked to leave ;-))
Ron W. Bill F. Bob E. found the 1402 card reader brushes were very frazzled.
Resulting in the following error report - (top right). Test card read is below
Better brushes right, gave better report - the bottom 3 of the report card. More work yet -
Ed disconnected the fan from the whole blower assembly (not shown), removed the fan rotor.
Stan and Ed cleaned the assembly and rotor.
The dust was really oily, condensed from near by oils and ribbon?
We picked off and rubbed off most of the grime then went to the janitor's closet wash sink and blasted off the rest
with warm water. Perfection :-)) We noticed the insert broken - but the mounting screw worked OK because its threads
pressed into the steel plate :-|
Frank King's son brought in some visitors. Stan, in the red suspenders, is acting as
tour guide and operator -
About the same time, there was a going away party for Allison Akbay, who is going to a position
in an art museum at Stanford University. We will miss her cheery smile and practical good sense -
Frank's words "Driver for paper stacker Drive Mechanism. Runs off of the hydraulic motor. Noise when first started
printer (I think)"
Joe's pencil points at a grove in the shaft. A seized bearing had been there. The shaft rotated in the seized
bearing - bearing and shaft will be replaced.
Most of memory now works: Robert replaced a defective core address driver to fix the inaccessibly of even 2K blocks.
- but "odd" gaps remain. The notes on the card indicate that the zone 7,000 to 7,999
and zone 11,000 to 11,999 has the following defects - 7090 through 7099, 7290 through 7299, ...
and a similar pattern starting at 11090 through 11099. Ron Williams notes that a similar problem in the German
machine was fixed by Bob Erickson doing some
high class soldering of core plane memory wiring.
As we were leaving the building, some delivery man asked if this was 1401 Shoreline. We asked "Didn't you see the
"1401" on the building? We are working on a machine called 1401." - But the 1401 seems to be missing from
the front of "our" building :-((
Today was apparently Tim Coslet's last full day in the Bay Area. Tim had been very helpful in restoring the CHM IBM 1620
to functionality. Over the past 4 years Tim, in spite of handicaps, has repaired most of the 100+ bad SMS cards removed from the
"German" IBM 1401. Tim supplied his own design in-circuit tester and his own scope for these efforts. His efforts
are greatly appreciated and he will be missed (like we have no one to replace his capability.)
Thank you Tim - Fare Well -
Allen reported that this summer's rocketeering was not totally successful - something about the second stage deciding
to go horizontal rather than vertical :-(
I suppose if you must, you must - It is a free country - mostly ;-))
We are all familiar with the medical variety - The medical
person puts some cold thing on your bare chest and says "Take a deep breath - hold it - hold it some more " -
well maybe not the last phrase ;-))
Well, dig this !! A stethoscope for machinery :-)) No more trying to couple a transmission to your ear
with a screwdriver, as a fake stethoscope
Frank wants Ed to listen for the various bearings in the 1403 transmission, and the hydraulic fluid
rushing about - this takes some familiarization !!
Allen Palmer is pointing to the many relays in a 729 Mod 2 that were replaced by transistor logic
on SMS cards in the 729 Mod 5 - giving considerably greater reliability in the Mod 5. The white arrow
points to a mechanical timer that helps control the timing of the LOAD and UNLOAD operations. This is
replaced by electronic timers in the Mod 5.
Here is Ed, probing about near the bus bars, while Joe Preston is paging about in the schematics
hoping to find some correlation between physical reality and the schematics :-| Actually all the voltages,
140, 70, 48, +- 12, +- 6 were quite close to nominal. The minus 6 was actually 5.75, while being restored
to 6.00, it showed signs of a dirty/noisy potentiometer (very jumpy when moved). One of the two fans in the area
did not function although it rotated easily when turned manually.
These are a few of the air filters that were removed from the 1401 and 1406, vacuumed,
and today replaced
Robert Garner
Report from Robert Garner
Isn't that a cute little three phase motor - most of us had never seen one that small -
We of course wanted to take it apart, but the screws wouldn't budge - sealed with Glyptol?
A quick raid to our spare 729s (classified as "educational" as opposed to the museum's "archival") provided a new fan assembly with two working fans :-)) - "Repair" complete :-))
Joe and Stan measuring the resistances between the three wires going to the little
three phase motor, two pairs of readings were about 600 ohms, the third was about 2 megohms :-((
Later in the afternoon, this next problem was solved by replacing another card -
and we can "sort-of" read a card into memory - about half the columns are correct - Now, is this
a problem with the character decode, or with the brushes in the 1402 reader/punch - or both -
or neither - stay tuned for
next week's episode ;-)) Will the villain drive the hero off the cliff??
There is a certain loss of dignity while sitting on the floor trying to bug-shoot the lower
1401 gates - Here is Robert, caught by the candid camera - checking if a changed circuit card
fixed a card read problem. Executing a card read command would clear all of memory, continuously
until halted. Fortunately this fixed the continuous clearing, but the card read command
now causes another fault - not quite so fatal.
Speaking of cards, here are 4 aging cheat sheets pasted under the front "cover" of the 1401
And speaking of cheat sheets, imagine you have to work with say 150 of these -
Ron Williams made a series of "aids" like this
And Judith brought in a room air filter - it was getting noisy. She and Bob Erickson disassembled it,
but I lost track of those goings on.
Stan Paddock brought in this "boy's toy", with no electrical diagram or instructions.
Now to put the chain on the two pulleys, with the "9" slug at the correct index point on one of the pulleys.
Inventoried here.
the spare SMS cards we got from
Connecticut, already sorted by Judith and someone
with the 6 drawers of German SMS cards
The current overflow from the drawers went into these boxes.
We can probably fix one more shelf in the set of drawers to hold cards. There were no 729 cards in the German
inventory - but fortunately there are some 729 specific SMS cards from Connecticut
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