[Rhodes22-list] IBM 409

Bill Effros bill at effros.com
Wed Aug 4 16:36:10 EDT 2004


Grayson,

Before the IBM 360 came the IBM 409 Accounting machine, which the telephone company used for billing.  (You sent back the card which said on it's face "Do not fold, staple or spindle" or something like that) along with your payment.

The 409 was a strictly mechanical deal.  Cards were cut off on 1 or more corners so you could make sure they were all aligned properly.  The cards were first sorted on a sorter, and then fed into the accounting machine, top edge first.

All of the machines had 80 wire brushes, one for each column, positioned over a metal drum.  The card acted as an insulator, preventing current from going through until the brush touched the drum.  The machine knew from a timing mechanism which number in each column allowed the current to pass through, and this information was stored in counters, which were then interpreted to derive information.

If a column was not designated as an alpha column there should be only 1 hole in it, but the machine did not reject 2 holes punched in the numeric section, it simply accepted the first it encountered.  This was always the lower number because the cards were always fed top edge first.  As soon as the machine encountered a hole in a numeric field, that number was stored in the register, and subsequent holes in the same field on the same card were ignored.

Punching holes above the intended number resulted in lowering the bill.  A second rectangular hole was not obvious to the humans who manipulated the cards, because alpha fields did have 2 rectangular holes in them.

Bank robbery sized sums of money were withheld from the phone company using this technique.  Early in the game, some people put Scotch tape over the higher value hole, however this was easy to spot, and turned out to be unnecessary.

It was clearly not in their interest for either IBM or companies using their machines to publicize this security breach, so it came to be known in some circles and not in others.  The electronic machines came along, in part, to address some of the difficulties encountered by electric motor driven mechanical accounting devices.

Bill Effros




----- Original Message ----- 
From: Grayson/Ena Lynn 
To: The Rhodes 22 mail list 
Sent: Wednesday, August 04, 2004 1:30 PM
Subject: Re: [Rhodes22-list] Lloyd's lettering pics


Bill:

Cute, but an urban myth nevertheless.

The standard IBM card format was 80 columns wide and 12 rows high, the size
of an old-style dollar bill.  Other companies used other formats to get
around IBM's patents, and IBM used a small 90-column card for a while on
their mid-range systems, but the standard card was king.

Each data element (number or text) was stored in its own group of columns,
one column per digit for numbers, by punching holes in the rows
corresponding to the digits 0-9.  The two top rows were numbered 12 and 11,
called "zones", and were punched out in various combinations with the
numbers to represent alphabetic symbols, numeric signs and punctuation.

As requirements became more complex additional punch codes were defined,
culminating in the Extended Binary-Coded-Decimal Interchange Code, IBM's
alternative to ASCII.  This 8-bit code, invented for System/360, defined 256
different card codes using up to 6 punched rows per column.  The card
itself, with 12 rows, could record 4096 different codes per column, so
nearly 94% of the possible punch combinations were "illegal" and could not
be processed.  In numeric card columns, less than 1/4 of 1% of the possible
punch codes were valid

The point is that even if you could find some way to punch extra rectangular
holes in your phone bill you could only invalidate the number and bring it
to the attention of a billing clerk, not make it lower.  I suppose you could
collect the punched-out chads and stick them back in the original holes, of
course, but the phone company would only credit your account with the amount
of your check, not pay off the account.  The '60s weren't as stupid as you
think.

Try robbing banks... that's where the real money is.

<G>
----- Original Message ----- 
From: "Bill Effros" <bill at effros.com>
To: "The Rhodes 22 mail list" <rhodes22-list at rhodes22.org>
Sent: Wednesday, August 04, 2004 11:02 AM
Subject: Re: [Rhodes22-list] Lloyd's lettering pics


I loved punch cards.  They read the first number they saw going from lowest
to highest.  If you took a rectangular hole punch and punched out a lower
number on your telephone bill and sent a check matching the lower number,
the telephone company would give you full credit for payment for that month.

It was the 60s.

Bill Effros


----- Original Message ----- 
From: Ronald Lipton
To: The Rhodes 22 mail list
Sent: Wednesday, August 04, 2004 10:11 AM
Subject: Re: [Rhodes22-list] Lloyd's lettering pics


I hated punched cards - I always spaced by the error when duplicating them

Ron
----- Original Message ----- 
From: "Michael Meltzer" <mjm at michaelmeltzer.com>
To: "The Rhodes 22 mail list" <rhodes22-list at rhodes22.org>
Sent: Tuesday, August 03, 2004 10:46 PM
Subject: Re: [Rhodes22-list] Lloyd's lettering pics


> it goes back to punchcards, column 72-80 was used for deck seq number, so
text wraps at column 72.
> So in the reply they add the ">" and wrap the column, BTW that is also why
vt100 were 80 columns were all the email "standard" were
> writen on.
>
> MJM
>
>
>
> ----- Original Message ----- 
> From: "ed kroposki" <ekroposki at charter.net>
> To: "'The Rhodes 22 mail list'" <rhodes22-list at rhodes22.org>
> Sent: Tuesday, August 03, 2004 9:05 AM
> Subject: RE: [Rhodes22-list] Lloyd's lettering pics
>
>
> Lloyd:
>
> When Todd answered your email, the last part of the image file name was
cut
> off.  This has been a frequent problem with sending images.  There must be
a
> limit on the size of the referenced file name.  After it gets to the
maximum
> size file name and then it wraps the rest of the file name in non-hot-key
> script.  Using cut and paste, to get the image you have add the wrapped
> (non-highlighted text) to the internet address to complete the correct
file
> name.
>
>
>
http://www.rhodes22.org/pipermail/rhodes22-list/attch/200408/02/attachment-0
> 001.jpg
>
> Ed K
>
>
> iginal Message-----
> From: rhodes22-list-bounces at rhodes22.org
> [mailto:rhodes22-list-bounces at rhodes22.org] On Behalf Of Todd Tavares
> Sent: Monday, August 02, 2004 11:51 PM
> To: The Rhodes 22 mail list
> Subject: Re: [Rhodes22-list] Lloyd's lettering pics
>
>
>    Lloyd,
>
>          Your original post with pictures is from June 2003  with the
>    subject line "FYI Letter Name Size"......FYI
>
>          Might save the headache of trying to re-post the pics.
>
>    Todd
>
>    ----- Original Message -----
>    From: lcrowther at cox.net
>    Date: Mon, 02 Aug 2004 14:52:35 -0400
>    To: rhodes22-list at rhodes22.org
>    Subject: [Rhodes22-list] Another try
>    > Name: not available Type: image/jpeg Size: 1053871 bytes Desc: not
>    available
>    > Url:
>    http://www.rhodes22.org/pipermail/rhodes22-list/attch/200408/02/attach
>    ment-0001.jpg
>    >
>    > Name: not available Type: image/gif Size: 2059 bytes Desc: not
>    available
>    > Url:
>    http://www.rhodes22.org/pipermail/rhodes22-list/attch/200408/02/attach
>    ment-0002.gif
>    >
>    > Name: not available Type: image/gif Size: 2055 bytes Desc: not
>    available
>    > Url:
>    http://www.rhodes22.org/pipermail/rhodes22-list/attch/200408/02/attach
>    ment-0003.gif
>    >
>    > __________________________________________________
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>
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