Interesting observation on real time listening on LF. When I was at sea
as a radio officer I arranged two receivers one vertical and the other
horizontal using the longwire 500 kHz antenna tuned to the same frequency
within one hertz. Then by using two headphones, each arranged so that
opposite ears listened to opposite polarizations, results were simply
amazing! With some very weak LF signals and especially with some ten
meter satellite signals, I would estimate the readability increased by at
least fifty percent. The ease in which signals buried in QRN could be
read was something I've wanted to investigate ever since that experiment.
Cliff K7RR
On Mon, 22 May 2000, John Rabson wrote:
----- Original Message -----
From: Kevin Ravenhill <[email protected]>
To: LF Group <[email protected]>
Sent: Monday, May 22, 2000 9:01 AM
Subject: LF: Re: Morse tones / filters etc.
> Has anyone experimented with phase shifted / delayed audio, i.e. with
"raw"
> audio fed to one half of the headphones and a (variably) phase-shifted /
> delayed version fed to the other half?
This reminds me of the Sterocode processor developed by G6CJ and (I think)
G3OTK, which was written up in September 75 RadCom. This unit took a mono
output from the receiver and produced a pseudo-stereo output to feed to a
suitable pair of headphones. It worked quite well on top band and even
helped on 80 m SSB in the evening when it appeared to spread out TV time
base QRM across a perceived range of directions of about 90 degrees . The
speech seemed not to be spread out so much. This is all highly subjective,
but it did seem to do something useful.
73 de
John Rabson G3PAI
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