From: "Des Kostryca" <des@kostryca.freeserve.co.uk>
To: "RSGB LF_Group" <rsgb_lf_group@blacksheep.org>
Subject: LF: Re:Simple Receivers For 136kHz
Date: Tue, 16 Nov 1999 22:26:09 -0800
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Mike Dennison wrote:

>However, here's where the trap lies. I could hear >DCF39 at S9+ and

>copied MM0ALM (650km) loud and clear. To a >beginner this might

>indicate that all was well. But what I could not hear >was the Greek

>RTTY which was S7 on the converter, the Loran or >any static.

and....
>if you don't get a HUGE signal from DCF39

>compared to your noise level, and can't hear the >RTTY just below

>136kHz most of the time, and can't hear Loran >and/or static all of the

>time, you may need to increase the receiver system >gain.


I most certainly fell in to this trap and actually reduced sensitivity of my
system at one point thinking I would improve dynamic range. Oops!  I have
now corrected my error and have spent the past few weeks improving front end
selectivity and sensitivity with positive results. I can now hear background
noise, static crash etc and the RTTY signal at 136kHz. However, I have so
far not heard Loran but to be honest I don't really know what Loran
interference sounds like. So I wonder if someone could please describe for
me the sound of Loran so I may identify the signal in future.

Many thanks and regards to all on the list.


Des.

Des Kostryca (M0AYF)  G.Q.R.P. no. 9788
I.A.R.U.  loc.  IO93OJ  W.A.B.  SK89
Member of the N.B.T.V.A.