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March's status report on the 1401 restoration project:
First, an "executive summary", then the more detailed status...

IBM 1401 CHM Restoration Project Report

by Robert Garner
March 20, 2005

High-level Status:
Objective: The goal of the 1401 restoration project is to bring the 1401 CPU and all of its peripherals up to full and complete operation. This includes all five of the 729 tape drives, the 1403 line printer, and the 1402 card reader/punch. After restoration, we expect it to run about once a week, for as long as a flourishing team can maintain and repair it. There is a plan on how 1401 programming classes and demonstrations could be conducted. Another project goal is to read-in and verify the card decks and tapes using the 1401 simulators, and record more history of the 1401 and the other unit record card handling peripherals of the era.

Status: There are about 5-8 retired IBM CE's and volunteers who regularly attend the restoration sessions every Weds and the 2nd and 4th Saturday's of the month (~6 days per month).

After about 3/4 year (~50 days of work), the hardware restoration project could be estimated to be somewhere around 30-40% complete. The mechanical paths in the card reader, line printer, and a tape drive are initially verified and ready to be tested together with the 1401 CPU. The CPU electronics are several months away from being fully operational. A higher-capacity 50-Hz power converter is finally being procured, so that the entire system can be operated together, thereby accelerating the bring up. (Up to now, there's only been sufficient 50-Hz power to run the CPU or the peripherals, but not both.)

Plans: Bring the new 18-kVA 50-Hz power source online and begin debugging all the peripherals together with the 1401 CPU. I expect the CPU, card reader, printer, and one tape drive will be mostly operational in about 3-4 months. The remaining four tape drives and the 1406 extended memory should be operational in about a year.

Detailed Status:

General/Team/Misc: About 5-10 volunteers (mostly retired IBM Customer Engineers, and Tim Coslet, also on PDP-1 team) regularly attended the restoration sessions every Weds and 2nd/4th Saturdays. Project web site: Some additional original 1401 documents were copied for 1401 machine room use. Several Tektronix scopes and carts were procured. There is a new policy for communicating the team's needs to the Museum staff: team members are asked to fill out a form in the room for requesting particular software, hardware, supplies, or manual copies. The 2nd Liebert cooling unit has been making loud compressor noises. (The other unit is not usable due to a bearing problem in its roof-top evaporator.)

Power: We've only had have sufficient 50-Hz power to operate either the 1401 CPU electronics or AC motors (in 729, 1402, or 1403), but not everything at once. Typically, the 1401 CPU is debugged in the morning, with peripheral debug in the afternoon. (With the 1401 electronics on, we're running at 96% utilization on one of the Elgar phase converters.) Peripheral motor path checking has now advanced to the point that further progress is not possible until the entire system is powered. The Museum has won its bid for an older 18 - 36 kVA Pacific Power static converter at IBM Cottle Road that will meet our power needs! We expect to see it delivered next week, and the Museum's electrician to connect it up after that.

1401 CPU: Ron & Bob made more progress debugging the 1401 electronics. They found that the same DC power supply that gave them trouble last month was acting up again, so they asked for permission to swap in the equivalent unit from the 1401 in visible storage (until this one can be properly repaired.) That allowed them to debug the memory access fault, which is still not solved.

1402 Card Reader/Punch: Bill and Don manually retimed the card read path and operated it via the motor for the first time. It sounded great! It currently jams - apparently due to a missing -6VDC from the (un-powered) CPU.

1403 Printer: The 1403 is ready for power to print. We're trying to work out how best to refurbish the old ink cartridges.

729 Tape: After much work by Allen and Glenn (and borrowing a take-up reel from the Museum), progress advanced to the point of being able to load a tape! The 10 stop capstan assemblies were manufactured by Annex Precision in Santa Clara. Grant will look at reproducing several broken 3-48 shoulder screws.

077 Collator: Bob, Frank, Tim, et al, began work on this very interesting piece of record unit equipment/art work! (See picture on web site.) The mechanical path is starting to become operational.

026 Card Punch: Operational now!

Software: Van Snyder and Dan McInnis (via his binary to ASCII converter) were very active interpreting and simulating what had been read-in from the Documation card reader (54 decks so far). Lots of work with SIMH and B1401 simulators and figuring out the very old 1401 binary programs! The Documation M600L reader stopped working couple weeks ago. Some repair work was started, but now suspended until ownership/status of the machine is confirmed.


General/Team/Misc: Schedule next all-hands meeting for April. (Now that we have the 50-Hz power converter coming.) Start using the paper form item request system.

Power: Hook up one 18-kVA rack of the Pacific Power unit and rock and roll! (We may need special slow-blow circuit breakers...)

1401 CPU: Continue to debug the 1401 memory read/write problem.

1402 Card Reader/Punch: Debug together with 1401 when full power up.

1403 Printer: Debug together with 1401 when full power up.

729 Tape: Continue debugging stand alone. Debug together with 1401 when full power up. Explore whether the Hitachi/ex-IBM machinist can re-rubberize capstans (as he did for the Santa Clara RAMAC restoration project).

Software: Bounce the 1401 class ideas off several folks at the Museum (incl Mike W, Karen, Chris, and Dag.) Repair the Documation (or get another unit) and finish reading in our punched cards and associated metadata.


50-Hz power: We're at a critical stage where installation of the new power converter will need to go smoothly/quickly.