IBM 557 Alphabetic Interpreter??

From: Dean Billing <drbilling_at_ucdavis.edu>
Date: Tue Mar 30 11:11:03 1999

At 09:41 PM 3/29/99 -0800, you wrote:
>On Mon, 29 Mar 1999, John Lawson wrote:
>
>> Do you actually *own* this, or just know where one is? Tres Cool!
>
>I might very soon. Its a huge beast! Too adorable to ignore.

Verily, it is a huge *beast*, and though adorable it should be ignored, IMHO.
Unless it is in perfect working condition, you probably will not be able to
restore it to working condition, especially if their is any appreciable wear
and tear on the print unit or the giant cams that are inside. The 557 was a
very unusual machine in the IBM tabulating line. I worked summers at
college for IBM field engineering during the 60's and the 557 was notorius
for needing constant maintenance. IBM kept incredibly detailed records of
every maintenance action on a piece of punched card equipment, since
practically all of them were rented at the time. The 557 was the hanger
queen of all tab equipment, consistantly the most maintenance intensive of
tab card machines. Open the covers and you will see why. There are two
giant cams, about 3' across driving the internals. It takes so much
mechanical energy to drive the print wheels, that the wheel cage is actually
skewed inside the frame, so that if all the print wheels are printing the
same character, they don't all fire at once. I have heard of field
engineers taking off the covers of a 557 for the first time, thinking that
the whole machine was trashed because the print wheel cage was torqued in
relation to the machine frame. When the machine runs it feels like a
washing machine out of balance and hops around the floor.

-- Dean
Received on Tue Mar 30 1999 - 11:11:03 BST