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Activity Report
Wednesday, October 6, 2004 - Regular "roll-up-your-sleeves"

by Ed Thelen

What a party! Beg pardon - "Work Party" - and for lunch we had free food (from another party that was breaking up)

- Some real estate folks had rented Computer History Museum for a noon gathering. Apparently they wanted to stay slim and didn't eat much. -
Many of the 1401 crew have just plain given up trying to be slim and trim, and enjoyed! ;-)

Robert Garner had published a big agenda and there was a big response. Was it nine people? I get confused if I have to use more than one hand to count. ;-((

Robert Garner brought a Megger to test the 1402 power connections before applying the 220 phase to neutral voltages (380 volts phase to phase!). Robert, Don Cull, Ron Williams, Don Erickson, and other experts went right to work, checking documents, wiring, circuit breakers, Megger readings, etc.
And they moved a missing circuit breaker from the Visual Storage 1402 to the "DE" 1402.
Allen Palmer removed a pair of drive belts from the 729 tape drives that drive one of the tape reels in one direction. (The ones with the notched bottom of the v-belt.) A spare from the big box of spare belts that Arnold supplied is shown for reference. These belts are about 56 inches long, and although operational should probably be replaced. The motor on the left with the arrow on it is the motor that does the fast rewind that IBM drives are famous for.
Steve Jasik arrived while we were removing a power supply from a 729 tape unit, and Allen Palmer showed him in great detail the challenges with the hardening rubber composition on the 729 tape drives. Steve took a sample pinch roller for further study and consultation with others.
Dave Cortesi giving some Tender Loving Care? - TLC - Unfortunately, I didn't catch Dave disconnecting the power supply and Allen Palmer (and me) lifting it out - just as well - the Three Stooges belong in the movies, not here. (Actually trying to label and disconnect *ALL* the wires for the 7 power supplies in the 729 power supply box the first time is surprisingly difficult!
Some unidentified photographer caught Ed Thelen getting ready to test capacitors in the just removed 729 power supply. It might have been Dave Cortesi or Dan McInnis?
The Elgar unit was fitted with a new (red) 5 pin socket, and the new cable to the 1402 was fitted with a new matching (red) plug. The current capability of the cable and plug from Germany had caused a lot of discussion - and this should be a *great* long term modern safe solution - even when we add all the tape units!
Ron Williams moving the Elgar unit to a handier location closer to the 1402.
Robert Garner re-strapped phase "A" of the Elgar unit to provide double voltage (220). Ron Williams, Don Erickson, and Ed Thelen turned the unit "ON" and verified the Phase A voltage (220) and frequency (50 Hz). We used the brand new fancy Fluke "Class 3" meter Robert Garner had just purchased.
(We had been teased about using a $7 voltmeter last time.)
I didn't catch Don Erickson soldering in a replacement IBM 108 power transistor (from Dave Babcock and the 1620 group) and replacing the power supply into the 1406.
And I didn't get a good picture of Allen Palmer who looked so trim and refreshed from European travels. (Actually he is hard to photograph because his head is usually deep inside a 729. Is this a safety issue? ;-)
And Frank King and Bill Flora are on vacation.
There was a lot going that I missed :-(
Long day,
and "the job ain't finished 'till the paperwork is done."
Ron Williams is doing a write-up in a logbook.

Published Meeting Agenda for this event :-)

here for reference

We've made sufficient progress on our AC wiring that there's a chance we'll be ready to flip on the juice!
Items to do include:
  1. Discuss the AC power wiring assessment. See last Saturday's initial report.
  2. Re-strap the Elgar for 380V phase-to-phase, 220V phase-to-neutral.
  3. Connect Elgar to the 1402 with the just-acquired, hefty, 3-phase, 5-wire cable and connectors. (Thanks to Dave Bennet for the power accessories!)
  4. Clean what we now believe is an Aluminum neutral terminal strip and apply anti-oxidant coating.
  5. Use a brand new 250/500V Megger to test the 1402/1401's AC wiring insulation. (We'll have proper DVM's on hand too.)
  6. Safety, safety, safety.
  7. (btw, more access badges have been arranged!)
Also, Steve Jasik, a new mechanical guru volunteer, will be meeting with Allen Palmer to discuss the 729 mechanical restoration, particularly the capstan rollers.
Also hear Allen's stories about his visit to the Deutsche Museum computer exhibits.
Suggestions, comments welcome!
Thanks again for everyone's hard work,
- Robert