7 Oct
2004
7 Oct
'04
8:02 p.m.
Hi,
John Lawson <jpl15(a)panix.com> said:
It is little known (but documented) that, during WWII, radio station KHJ
in Los Angeles ( and undoubtedly many others ) sent radio-teletype signals
by shifitng the carrier a miniscule amount - I think about 10 htz, and
using a very slow baud rate. This would not be noticed by the average
equipment of the day, and would take very specialized gear to recover,
store and print
But it allowed messages to be sent large distances by powerful
transmitters - completely 'in the blind'.
The BBC still do this on their 198KHz long wave transmitter, easily heard
by switching the receiver to ssb mode.
--
Cheers,
Stan Barr stanb(a)dial.pipex.com
The future was never like this!