Message-ID: <$EFdbGAbFRP5EwTv@pickmere.demon.co.uk>
Date: Tue, 6 Jun 2000 15:57:31 +0100
To: rsgb_lf_group@blacksheep.org
From: "M.J.Powell" <mike@pickmere.demon.co.uk>
Subject: Re: LF: Re: Copying CW
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In message <E12zIkh-0003zU-00@mserv1b.u-net.net>, Mike Dennison
<mike.dennison@rsgb.org.uk> writes
>Dick, PA0SE wrote:
>> I have tested "pseudo-stereophonic" reception of CW by feeding the halves
>> of a stereo headphone via series tuned circuits resonating at  1002 and
>> 842Hz (922 ą 80Hz)  respectively. At first the result  was pleasant; it
>> sounded like being in a room with the wanted 922Hz signal in the centre.
>> But it did not take me long to find out that it contributed absolutely
>> nothing to the readibility of signals under difficult conditions.
>> It proved again that our sophisticated ear/brain system cannot be helped
>> by such primitive contraptions.
>
>Yes, I'm aware of this but am keeping an open mind. I have already
>done some interesting tests that combine some of the advantages
>of both analogue and digital techniques. One crude test last
>weekend produced significantly better readability of a weak station
>in heavy static than was available either direct from my radio, or via
>a DSP unit.
>
>What sparked off this idea was the number of people who agreed
>that listening to a pair of headphones on the bench gave them
>better reception than when the phones were on the head. Therefore
>there appears to be at least one uninvestigated way of enhancing
>reception which at present relies on chance and acoustics.
>
>I agree that all theoretical work tends to ignore the colossal
>advantage of using the brain, but I am not a theorist and would like
>to find ways of helping the brain along a bit.
>
>Thanks very much to all those who replied re time delays.
>
>As soon as I have reached some conclusions I will report my
>results - or that Dick is indeed right and the brain can't be helped at
>all!

Don't forget the old trick of fixing a loudspeaker to the end of a pipe
and using the organ pipe resonance frequency. Quite common in the 40s
and 50s. I wonder if two could be used, tuned to different frequencies
and placed at opposite ends of the room?

73


Mike 
-- 
M.J.Powell