[GreenKeys] UNIVAC Products 1947-1959 computers p-tapei/o and so much more!

[Chris Elmquist]

Pretty cool for 1957,

http://ethw.org/First-Hand:Building_the_U.S._Navy's_First_Seagoing_Digital_System_-_Chapter_4_of_the_Story_of_the_Naval_Tactical_Data_System

Communications between the unit computer and the data terminal set
were to be in the standard NTDS 30-bit parallel mode. The data terminal
set took the 30 parallel lines two at a time and fed them to 15 human
audible tone generators, having much the same sounds as a touch tone
phone. Signals on each pair of lines were translated to shift the phase
of the tone generator to one of four quadrature phases. A two-bit binary
number can be any one of four combination of ones and zeros, so each tone
generator could represent a two-bit binary number, and the 15 generators
in parallel could represent a 30-bit word. The human ear can not detect
phase changes in a musical note, but at the receiving data terminal the 15
musical tones were fed to 15 very sensitive electromechanical resonators,
each ‘tuned’ to one of the 15 tones. The resonators could be quenched
and then quickly reactivated as each parallel word was received. When
reactivated, each resonator would vibrate in phase with the newly
received tone. Electronic circuitry could detect the phase of vibration
with respect to a reference tone, and the circuitry would convert the
received transmission burst as a 30-bit parallel signal to be sent to
the receiving computer. The radio and data terminal combination could
transmit seventy five 30-bit words per second. [Collins Radio Company,
Kineplex, Collins High Speed Data Transmission System, Oct. 1957, p 9]


On Wednesday (10/07/2015 at 01:57PM -0400), Nick England wrote:
> And the on-line story of NTDS
> http://ethw.org/First-Hand:No_Damned_Computer_is_Going_to_Tell_Me_What_to_DO_-_The_Story_of_the_Naval_Tactical_Data_System,_NTDS
> 
> greenkeys alert - photo of the modified 28ASR for NTDS
> http://ethw.org/File:Teletype_2_.jpeg

-- 
Chris Elmquist