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[carlsaff]

http://www.newscientist.com/article/mg20727772.100

Cool.

[Garrett H]

Harry Nyquist was doing much of his work in the 1920's.  His sampling theorem was published in 1928 when covering topics related to telegraph transmission.  Of course, no one was thinking about PCM digital at the time.  But its amazing to see how the foundations of technology are often presented well before the application is realized.

[CWHumphrey]

Harry Nyquist...1928...Bell Labs.

Cheers,

[dcollins]

carlsaff wrote on Sat, 18 September 2010 16:18

http://www.newscientist.com/article/mg20727772.100 Cool.

This was the first use of PCM to transmit speech:

http://www.nsa.gov/about/cryptologic_heritage/center_crypt_h istory/publications/sigsaly_start_digital.shtml


DC

[carlsaff]

The 1928 Nyquist bandwidth theorem *implied* capture and regeneration of signal, but it didn't specifically deal with the issue of signal sampling. It wasn't until Nyquist–Shannon in 1949 that there was a theorem explicitly dealing with  sampling/regeneration of continuous signal.

The Reeves article caught my eye because he designed an actual analog *circuit* in 1937 that (despite being impossible to build at the time) would've performed an analog version of digital sampling.

Great article about the first actual PCM transmission there, DC!

[CWHumphrey]

carlsaff wrote on Sun, 19 September 2010 04:05

The 1928 Nyquist bandwidth theorem *implied* capture and regeneration of signal, but it didn't specifically deal with the issue of signal sampling. It wasn't until Nyquist–Shannon in 1949 that there was a theorem explicitly dealing with  sampling/regeneration of continuous signal. The Reeves article caught my eye because he designed an actual analog *circuit* in 1937 that (despite being impossible to build at the time) would've performed an analog version of digital sampling. Great article about the first actual PCM transmission there, DC!

Fair enough.  However, Claude Shannon published his information theory in 1948.

Cheers,