From: DL4YHF@aol.com
Message-ID: <4d.224d2fec.2a8514c9@aol.com>
Date: Fri, 9 Aug 2002 08:51:21 EDT
Subject: LF: Re: SM6LKM Jason beacon
To: rsgb_lf_group@blacksheep.org
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<HTML><FONT FACE=arial,helvetica><FONT  SIZE=2>Hello Jim, Johan and group,
<BR>
<BR>Also tried to copy Johan's beacon with quite little succes. A lot of harmonics from AC mains around 7.000 MHz reducing the RX's sensitivity.
<BR>
<BR>IMO, the effect described by Jim may be caused by this:
<BR>Turning the AGC off, and let the signal clip quite 'early' in the receiver reduces the time when the RX is deaf after a static crash. The system recovers very quickly to the mean sensitivity level. Some receivers have different speed settings for the AGC which give totally different results on the waterfall screen.
<BR>
<BR>I don't think its an overflow in the soundcard's ADC, also not in the software (you would see this in SL's small input monitor screen where the waveform of the digitized signa can be observed. Also, most PC-based programs nowadays use floating point numbers which makes digital signal processing easier and even faster. Sure Jason also uses floats for the maths.
<BR>
<BR>
<BR>Hope to receive / see / hear you later.
<BR>
<BR>WX here is also very PUNNY at the moment :) with lots of QRN.
<BR>
<BR>73 Wolf DL4YHF.
<BR>
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