Don't forget, Mal still uses cats whiskers and coherers - that's why he
needs large antennas and keeps on asking everyone to use QRO amplifiers and
antennas that need 2 acres of ground space because he cannot hear them :-)
But more seriously, I rather agree with Andy, unless you need fancy
directional processing for the rx side you only need to be external noise
limited - all the naval systems (that I've dealt with...) use active rx
antennas and serious multicouplers. Tx uses as much metalwork as they can
get up there, generally whips. Subs also use active antenna probes and loops
for vlf (rather a critical area you might think....) - rather less
interested in transmitting though:-)
But it would be nice to have the space and low noise level that Mal seems to
have........

Paul   G8GJA
-----Original Message-----
From: Dexter McIntyre W4DEX [mailto:[email protected]] 
Sent: 03 January 2012 15:02
To: [email protected]
Subject: Re: LF: Antennas

What commercial two way LF stations still exist?  All that I know of just
transmit.  Way back when there was two way LF traffic a high level receive
signal was needed for the cat whisker detector to work :)

Dex

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