[vcf-midatlantic] Univac, our first real work!

Bob Flanders bob.flanders at gmail.com
Mon Jun 13 16:31:02 EDT 2016


This article talks a bit about the 1219 system


On Mon, Jun 13, 2016 at 4:24 PM, Bob Flanders <bob.flanders at gmail.com>

> Very cool. Reminds me of the AN/UYK-7.
> As you deal with problems (like gooey rubber, etc.), you may want to check
> out this blog:
> https://rescue1130.blogspot.com/
> Carl Claunch has ad to deal with a lot of these types of problems while
> restoring an IBM 1130. You may find some similar items in the blog, or ask
> Carl if he has dealt with similar problems and his solution.
> Bob
> On Mon, Jun 13, 2016 at 4:01 PM, Evan Koblentz via vcf-midatlantic <
> vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:
>> Hey everyone,
>> Our workshop this past weekend had the usual highlights -- we repaired
>> all sorts of 8-bit stuff, monitors, did some programming, enjoyed plenty of
>> nerdly shenanigans -- but by far the highlight was when Duane C. and Bill
>> Drom. told me the Univac 1532 I/O console (paper tape + Model 35 teletype)
>> was ready for its first power up!
>> Background: We acquired a complete-ish Univac 1219-B mainframe about six
>> years ago. One tape drive was on display for a few years in our old museum,
>> and much of the full system was on display as one of the VCF East shows,
>> but mostly the computer lived in our warehouse. That changed this spring
>> when we opened the new museum: its double doorway enabled us to put the
>> computer on permanent public display. We cleaned it on the outside.
>> Bill Drom. and Duane, who both used this model of Univac in their Navy
>> days, jointly approached me ahead of this past workshop and asked if they
>> could start technical work by modifying one of the console units for a
>> modern power supply. They assured me it's safe and easily reversible to the
>> original configuration, so I said yes.
>> A summary from Duane about what they actually did:
>> >> The +/- 15 and -4.5 switching supplies fit in the space we removed the
>> 400 Hz. transformer-diode assembly. The -28 volt supply wound up in the air
>> channel at the bottom. We bypassed the 400 Hz. power on relay and have to
>> turn on with a external switch. Does anyone have a feel of what 60 Hz.
>> voltage would pick a 115 Volt 400 Hz. relay? if it is a straight inductance
>> problem it would be 17.25 volts . We left that for a future visit when we
>> have a variac to play with. We did not have time to trouble shoot all the
>> problems the 1532 had. at first the logic was so crazy that we put in a
>> logic drawer from another unit. turns out the display unit was missing
>> cards. The rubber on the reader capstan had turned to a gooey mess and
>> peeled off onto the tape we tried. If none of their consoles has a usable
>> pinch roller they will have to send it off to a service that does that sort
>> of thing. Maybe we could try some of the liquid rubber that is made to dip
>> tool handles in. The punch is punching extra bits. The oil on the TTY was
>> all dried up and at first the TTY would not do anything. It took about an
>> hour of oiling and moving stuff by hand until it gradually came to life.
>> The tape chute has the bracket that holds it up under the punch broken so
>> the tape gets snarled coming out of the punch. It will be easier to swap
>> out the tape drawer than to try to swap the chute. I put in a new one once
>> and it took me about a hour to figure out how to get it in without bending
>> it. <<
>> Saturday night, when only the power supply was installed, about a
>> half-dozen of us went into the museum room and observed the first power-up.
>> Here's the video... well actually it's take two; the first time I
>> idiotically recorded it with my phone in portrait mode. :)
>> https://www.youtube.com/watch?v=SQCSGF5Suxo
>> We have three more of these console units in storage, along with one
>> extra CPU and one extra tape drive, which is all very helpful for
>> parts-swapping.
>> This is an exciting milestone for us! I'm going to send a note to the
>> nice people who gave us the system as well.

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