The KW-26 was an on-line crypto for teleprinters and could run at speeds up to 74.2 baud.

Five minutes before "HJ" or crypto restart, the transmitter was recarded and a phase put up by the a sending station. (The term HJ's was used initially with the 26, but later became accepted as the term for timed restarts for any system). One hoped that the receiving station was using the same sequential card deck and placed the right card in the reader of their receiver.  If not, well, you can bet what fun that was. The receiving station upon receiving a phase, would get an alarm indicating that the circuit was not in sync. The receiving station replaced his card and would in turn place his transmitter in phase and replace his card.  Once both units were sending a phase to each other and at the appointed HJ time, each would go to live traffic.  If everything worked like it  was supposed to, the the system would drop into sync and traffic would start pouring out of the Model 28 or Model 40 Teletype machines. If not, a lot of secure voice coordination went on verifying the right key cards and card numbers.

One annoying problem was with the card readers. They were designed for "once-use" cards. Once the card reader was closed, it cut the key card in half. Well, on more than one time, a card would slip while closing the card reader door and would spoil a card in sequence.  When that happened, a secure voice coordination link was immediately set up to coordinate card replacement. You knew the key card slipped when you could see the corner of the card protruding from the side of the reader.  If all went well, only two cards were used during a 24 hour period.

Where I was stationed, the card readers were so old and worn out, a hammer was hung on the latching handle.  Upon closing the door, the hammer was used to tap the surface of the card reader to make sure the worn pins made contact with the other side of the reader.

Contributors: Jerry Proc
Curtis Law, Kodiak Military History Museum

(George's Note: We had two of these at CFB Ottawa (N) Tape Relay Centre to the Yanks. No photo available, but check out the KWT 37 on Jerry's pages and you get a good idea of the nature of the beast. On the operations side, the circuit always churning out tape at 100 wpm so we were quite happy when it was down, which was frequent. Sending was a pig because of the automatic numbering equipment, always lots of open channel numbers when new operators were on our send bank.)
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