Message-ID: <3728E0B2.DC2A73E@netins.net>
Date: Thu, 29 Apr 1999 17:44:03 -0500
From: "Doc Gruis" <donnatom@netins.net>
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To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: Re: Weekend report 24/25 April
References: <006101be928e$482ef1c0$0600a8c0@prstesv1.prestel.co.uk>
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    Interesting.  Here in the States I have had much better luck in using a
capacitor to couple to the telephone lines.  The intensity of the noise does not
seem to be quite as intense.  This has worked for me for LW through SW.  I
usually use a fairly large capacitor, 0.05 or so as the primary isolator, and a
high resistance resistor, ca. 100 K or so, as a static drain from the low side
to earth.

Doc - K0HTF  EN31dx  (Iowa, USA)
___________________________________________________________

Dave wrote:

> Chaps..
>
> I have tried sucking some RF off the mains by connecting the primary of a
> small transformer from the mains supply down to earth via a 22nF capacitor.
> The secondary was then used to feed into the receiver in the hope of
> cancelling Mains-bourne intereference. Unfortunately the interference I
> picked up from the mains seemed to be primarily that from my own house which
> I can cure myself! The stuff from other sources didn't seem to be present on
> my own mains supply...  This obviously depends on the individual situation
> but it didn't work for me.
>
> Good luck anyway!   Dave G3YXM.
>
> >> As most of this local qrm seems to be borne on the mains wiring has
> anyone
> >> tried taking a signal directly from the mains rather than from a separate
> >> "noise antenna"?
> >>
> >> Mike ZL4OL
> >>
> >
> >I will certainly try this, though I think the TV and games machine
> >QRM is radiated by the TV antenna coax outer. Making a crude
> >braid breaker (100pF in series with each leg of the coax) fixed the
> >S5 QRM from my own TV.