> the 407 used relays Could be. I never really worked on a tab machine. I used them to "80-80" duplicate a card deck, or to print or interpret a card deck. Shops had boards lying around permanently wired for those tasks. "Interpreting" cards consisted of printing across the top whatever was punched into the card. Manual card punches (026 and 029) could print all 80 columns across the top of the card, but a tab machine only printed 60 columns across the width of the card. (Obviously the printing did not line up with the columns.)
I started on Wall Street in 1968 and both tab machines and 1401's were in common use, but I never programmed either. My first real programming was on 360's. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Seymour J Metz Sent: Sunday, May 29, 2022 5:30 PM To: [email protected] Subject: Re: Tabulating Machines (was "... z114") I've used a mechanical Marchant calculator, but the 407 used relays. The boards for tabulators were a lot heavier than the boards for other EAMs, e.g., interpreters. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List [[email protected]] on behalf of Charles Mills [[email protected]] Sent: Sunday, May 29, 2022 8:11 PM To: [email protected] Subject: Tabulating Machines (was "... z114") I have never programmed a Tab machine but here is what I know. The addition and so forth was purely mechanical. Anyone remember old-fashioned mechanical adding machines? Picture a wheel with ten cogs on it numbered 0 through 9. Let's say it is indicating 5. If you turn it three clicks it is now indicating 8. Voila! 5 + 3 = 8. Let's say you turn it three additional clicks. It is now reading 1, and on the way from 9 to 0 it poked the wheel to its left one position. 8 + 3 = 11. Yes, the plug board's purpose was to hold the wires so you could take them out of the tab machine as a unit, put it on a table, and program it, and put it back. The board itself was a passive carrier. The holes were principally of two types: "hubs" and "emitters." Think of a number as "coming out of" an emitter and going into whatever hub you plugged the wire into. Let's say you wired the emitter for card reader column 10 to printer column 20. Every time a card was read it would print whatever was in column 10 in column 20. The numbers did not come out of the emitters in binary like ASCII going down a telegraph wire; it was all timing. The card went by a read station consisting of wire brushes and a bronze (?) cylinder. If the 5 hole was punched it would emit a pulse as the 5 row went by the read station. The printer had a revolving print head. If you pulsed the hub as the 5 went past the page a hammer printed a 5. Was I clear? The most advanced tab machines were quite sophisticated. They handled alphanumeric data punched in the cards and printed. There were "accumulators": if you wired card column 10 to the accumulator it added whatever was in column 10 to the accumulator. There was some sort of conditional logic that would let you output the sum in the accumulator. It was real successful for IBM. So much so that their first computers were numbered similarly: 701, 704, and so forth. IBM's first computers used punched cards because (a.) that encouraged customers to transition from 407's to the new computers; and (b.) IBM had a lucrative business selling punched cards and did not want to give it up. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Doug Sent: Sunday, May 29, 2022 1:55 PM To: [email protected] Subject: Re: my new z114 The "boards" were maybe 1 inch thick, with holes in them. You put an overlay over the board (depending on what you were programming) and inserted wires between the holes based on the overlays. My father programmed these things for a bank on Long Island NY. The wires were of various lengths depending on how far they had to reach. They were mabe 12inches by 12 inches, and went into a receiver, and then were snapped into the machine. After I went to 360 Common I/O school, I went to work for Sorbus for awhile and had to deal with them there, but I never could program them. Doug Fuerst ------ Original Message ------ From: "Grant Taylor" <[email protected]> To: [email protected] Sent: 29-May-22 15:23:01 Subject: Re: my new z114 >On 5/29/22 12:26 PM, Seymour J Metz wrote: >>You could theoretically add wires without removing the board. I've never seen it done and I suspect that it's not safe. > >I'm now getting the impression that the wires were sort of latched into the board and the plugboard tool was used to unlatch wires for insertion and removal. > >The idea of plugs & wires being latched into the board makes more sense as far as inserting & removing the entire board from the system. As if the board is simply a passive frame that holds the plugs & wires in place while the actual jack for the plugs remains in the system. > >I have no idea if this is remotely correct, but it does make a LOT more sense to me than removing and inserting boards with a bunch of jack in them. > > > >-- Grant. . . . >unix || die > >---------------------------------------------------------------------- >For IBM-MAIN subscribe / signoff / archive access instructions, >send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
