Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss
Radiation
1 view
Skip to first unread message
Taylor
Dec 30, 2011, 4:26:39 PM12/30/11
to
About 60 years ago I had access to a variety of test equipment,
including a National receiver capable of receiving signals as low as
transmitters operating in the audio band.
I connected an antenna to the output of an audio oscillator and
another on the National HRO?? receiver .
To my surprise I had a carrier on the receiver. There was no
modulation but if I had modulated the signal with a frequency lower
than the carrier frequency, I am convinced that I could communicate.
I know that Long wave transmissions used to be common but are those
frequencies being used for any type of communications.
I know that whales, sonar, bats, etc use audio signals to navigate or
communicate but I am talking at about RF communications not audio. To
receive them we need a receiver not a microphone.
Is that used to communicate with submarines, mines etc ???
including a National receiver capable of receiving signals as low as
transmitters operating in the audio band.
I connected an antenna to the output of an audio oscillator and
another on the National HRO?? receiver .
To my surprise I had a carrier on the receiver. There was no
modulation but if I had modulated the signal with a frequency lower
than the carrier frequency, I am convinced that I could communicate.
I know that Long wave transmissions used to be common but are those
frequencies being used for any type of communications.
I know that whales, sonar, bats, etc use audio signals to navigate or
communicate but I am talking at about RF communications not audio. To
receive them we need a receiver not a microphone.
Is that used to communicate with submarines, mines etc ???
0 new messages