Message-ID: <3B879A02.A5F09400@alg.demon.co.uk>
Date: Sat, 25 Aug 2001 13:28:50 +0100
From: "Steve Rawlings" <steve@alg.demon.co.uk>
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To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: Re: carriers
References: <3B867C3D.42A9DB5B@netscapeonline.co.uk> <006d01c12d53$e09ff780$0eef7ad5@dave>
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Dave G3YMC wrote:
> I was also listening yesterday and can confirm that nothing was heard
> here in Bracknell. 
As with Alan and Dave, I did not hear the carriers either.  It
would seem to be a noise source that is local to Mal.  But Wolf's
report that LF noise from TV sets can travel hundreds of metres
is a concern.

 In addition, Wolf wrote:
 > As alternative, I am very curious about Steve's and Rob's noise
 > canceller experiments. IMO, cancelling more than one QRM source 
 > is a tough job. 
 Yes, cancelling, say, two QRM sources, requires two cancellers,
 with a distinct sample of each noise source.  It is also very 
 difficult to obtain a large enough sample of the noise if the 
 noise source is hundreds of metres away.  Interestingly, I've had 
 the greatest success with my noise canceller where the QRM has been 
 conducted via the electricity supply ('mains'), from a neighbouring 
 house into mine.  Then, there is no problem obtaining a sample of 
 the noise!

> I heard Bob back on the band this morning, perhaps he is now having
> some success with his noise canceller.
Bob is indeed having success, but he now needs a pre-amp to
compensate for the loss through the canceller.  So Bob has
ordered a G0MRF receive pre-amp.  Meanwhile, Bob will be
conducting more experiments to improve the sample of QRM being
fed to the noise canceller.

Regards to all,
Steve GW4ALG