HY-2 VOCODER (Voice Coder)
Designed in 1961, this device was used for converting speech
into a form compatible for encryption by a general purpose key generator
(ie KG-13) and transmission over a narrowband radio or telephone channel.
It was a 16-channel, 2400-bps system using “Flyball”
color-coded modular logic to reduce the weight to 100 pounds.The HY-2 was
widely deployed in Vietnam but according to NSA web documents, President
Johnson refused to use the HY-2 because of its poor "Donald Duck" sounding
quality. Its wide deployement is confirmed by its use in AUTOSEVOCOM I,
a worldwide secure voice network used by the US government in the 1960's.
The HY-2 was the last generation of channel
vocoder technology in the US.
|This example of the HY-2 can be found in the National Cryptologic
Museum. (Photo by Doug Eyre)
|Another view. (Photo by Vin Simmons)
|Closeup of front panel. The meter face indicates it
was made by Honeywell.
|Closeup of National Cryptologic placard.
|Both images in this table are deratives from Ralph
Credits and References :
1) Doug Eyre, Hewitt, TX
2) A History of Secure Voice Coding http://www.nsa.gov/publications/publi00048.cfm
3) Vin Simmons <vinsimmons(at)aol.com>
4) Ralph Simpson <ralphenator(at)gmail.com>
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