From: DL4YHF@aol.com
Message-ID: <149.7b0813.28b8e0b8@aol.com>
Date: Sat, 25 Aug 2001 07:06:32 EDT
Subject: LF: Re: Carriers
To: rsgb_lf_group@blacksheep.org
MIME-Version: 1.0
Content-Type: text/html; charset=windows-1252
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Sender: <majordom@post.thorcom.com>
Content-transfer-encoding: 8bit

<HTML><FONT FACE=arial,helvetica><FONT  SIZE=2>Hi Mal and Alan,
<BR>
<BR>I can strongly confirm such QRM from modern TV sets. That also seems to be 
<BR>the reason why some days I "don't have ears" when operation from DF0WD. 
<BR>On a spectrogram, you can see the 50- or 100-Hz-spaced lines drifting around 
<BR>slowly.
<BR>Also confirm the range of these nasty carriers: they can indeed exceed the 
<BR>range of 100 yards (~meters). The clubstation DF0WD is about 150mtrs away 
<BR>from the next house, but a part of QRM seems to correlate with the TV prime 
<BR>time. On the waterfall its impressive to see a group of carriers disappearing 
<BR>instantly after the main evening news at 20:15 local.
<BR>
<BR>I guess most of the QRM travels over the mains supply lines. I already 
<BR>considered building a battery-powered remove RX with a 70cm-FM-link to the 
<BR>main station (using a cheap 70cm-LPD handy). The problem is finding a quiet 
<BR>remote RX side where the RX cannot be vandalized or stolen.
<BR>
<BR>As alternative, I am very curious about Steve's and Rob's noise canceller 
<BR>experiments. IMO, cancelling more than one QRM source is a tough job.
<BR>
<BR>Good luck to all,
<BR> &nbsp;hope to c u &nbsp;on 136kHz,
<BR> &nbsp;&nbsp;&nbsp;Wolf &nbsp;DL4YHF.
<BR>
<BR></FONT></HTML>