QUOTE
Sometimes it just takes time to work out the kinks.
Sunday, May 29, 2005; Page B08
The next time you're distracted by the ringing of someone's cell phone, consider this: Washington is the birthplace of the blessing -- or the curse -- of wireless telephony.
This Friday marks the 125th anniversary of the world's first wireless telephone call.
....
On June 3, 1880, Bell's collaborator, Charles Sumner Tainter, set a transmitter atop the Franklin School, a building that still stands at 13th and K streets NW [in Washington DC]. With Bell manning a receiver in his laboratory 700 feet away at 1325 L St. NW, Tainter uttered the less-than-immortal words, \"Mr. Bell, if you hear what I say, come to the window and wave your hat.\"
Incredibly, 15 years before Guglielmo Marconi's first successful radio transmissions, Tainter saw the hat wave.
Bell's device relied not on radio waves but on sunlight. His \"photophone\" used an array of mirrors and lenses, with the vibrations from the speaker's voice modulating a beam of polarized light.
A parabolic reflector at the receiving end collected the beam, focusing it on a selenium cell that converted the modulations into electrical signals. The signals fed to a telephone earpiece and became sound.
....
-- Mark Eckenwiler
photophone@datagram.org
Sunday, May 29, 2005; Page B08
The next time you're distracted by the ringing of someone's cell phone, consider this: Washington is the birthplace of the blessing -- or the curse -- of wireless telephony.
This Friday marks the 125th anniversary of the world's first wireless telephone call.
....
On June 3, 1880, Bell's collaborator, Charles Sumner Tainter, set a transmitter atop the Franklin School, a building that still stands at 13th and K streets NW [in Washington DC]. With Bell manning a receiver in his laboratory 700 feet away at 1325 L St. NW, Tainter uttered the less-than-immortal words, \"Mr. Bell, if you hear what I say, come to the window and wave your hat.\"
Incredibly, 15 years before Guglielmo Marconi's first successful radio transmissions, Tainter saw the hat wave.
Bell's device relied not on radio waves but on sunlight. His \"photophone\" used an array of mirrors and lenses, with the vibrations from the speaker's voice modulating a beam of polarized light.
A parabolic reflector at the receiving end collected the beam, focusing it on a selenium cell that converted the modulations into electrical signals. The signals fed to a telephone earpiece and became sound.
....
-- Mark Eckenwiler
photophone@datagram.org