Message-ID: <000101bed305$4e4e3cc0$6eeeabc3@default>
From: "Alan Melia" <Alan.Melia@btinternet.com>
To: "rsgb_lf_group" <rsgb_lf_group@blacksheep.org>
Subject: LF: A help with rx sensitivity ??
Date: Wed, 21 Jul 1999 00:09:08 +0100
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Mike G3XDV, mentioned using DCF39 as a standard signal for comparing aerial
performance, in a previous exchange which culminated in the fascinating
article and results reported by Dick PA0SE. This has just surfaced again for
me as I have had another packet contact with F5MLP. As you may remember he
has erected a 300m wire in anticipation of getting a permit for 136. He is
disappointed in its performance, and has sent a bull round the packet
network asking for other stations reading of the strength of DCF39.

It occurs to me that this is a fairly meaningless quest unless the stations
replying are really 'switched-on' to LF aerial tuning and performance. It
also occurs to me that a definitive list of measurements on the station from
different locations might form a useful guide to newcommer's to the band
 as well as lazy old ones like me!)
I don't want to clog the reflector with what many might regard as junk, so I
am suggesting that I am willing to collect and collate (via e-mail to my
personal address below) any reports that you would like to send to me
direct.
As a guide may I suggest :-
Call    Locator  Aerial  Receiver  (S-meter )   DCF39   DCF39      noise
level
                                              Calibration)    (day)   (after
dark) (quiet day)
There is a lot of room for discussion on what is important and what is not,
but maybe this could serve as a basis to collect some guidance data.
I know we think that there is not much difference in the day and night
signal from the station, but does everybody find it so? As for the s-meter
calibration I am thinking of something like 'S-9 = 50uV' or something
similar. If the formula that Dick refers to does work we should be able to
work out the field strength at any location in the reception area of DCF39.
Qualifying comments accepted, if you care to add them.

When I have collected a reasonable number of reports I will post the results
as a digest to the reflector for all to see.
I hope you will see this as a worthwhile exercise and deluge me with
reports!
73 de Alan G3NYK
Alan.Melia@btinternet.com