LF: CT1DRP's overnight plots

To:	[email protected]
Subject:	LF: CT1DRP's overnight plots
From:	[email protected]
Date:	Sun, 27 May 2001 05:40:24 EDT
Reply-to:	[email protected]
Sender:	<[email protected]>

Hello group,

The automated RX facility run by Brian CT1DRP works beautiful now, here a few
suggestions how it can be used.

I tried to be 'heard' by Brian's RX system on late saturday night (May 26),
transmitting a sequence very long dashes at full hours. It succeeded again,
though only about 80mW were used here (at DF0WD, loc. JO42DF).

The transmissions were at 19,20,21,22 and 23 UTC, with those at 22 and 23 UTC
being visible in the "TA plot" (which shows the peak amplitude between
135.915 and 135.927kHz as a function of time for a few hours).

The peaks are visible when the signal from DCF39 reaches the maximum during
the night (not a surprising fact, because DF0WD is only a few 100km away from
DCF39). It would be interesting now to see, if this is also true for signals
transmitted from other parts of EU.

The plots can be loaded from
http://homepage.esoterica.pt/~brian/Graphs.htm
Though Brian says the site is still "under construction", it is already a
very useful installation and we should make effective use of it. It would be
even better to have more such RX facilities around... but not all of us have
the opportunity of letting their PC's run all night. Hw abt u.. ?

We could set up a (manually operated) system of transmitters similar to the
NCDXF international beacon project (avoiding the word 'beacon' of course, and
using an other frequency than the TA slot).

With 6 stations (A-F), each transmitting a 5-minute carrier like this:
20:00-20:05 A transmitting
20:05-20:10 silence
20:10-20:15 B transmitting
20:05-20:10 silence
20:20-20:25 C transmitting
20:05-20:10 silence
20:30-20:35 D transmitting
20:05-20:10 silence
20:40-20:45 E transmitting
20:05-20:10 silence
20:50-20:55 F transmitting
20:05-20:10 silence

Why 5-minute carrier ? Because CT1DRP's automated RX configuration collects
(integrates) the spectra in long intervals to eliminate QRM ("pull weak
signals out of the noise"). If a measuring interval is 90 seconds long, you
need at least 2*90 seconds to be shure you hit at least one "full" measuring
interval. If not, the peak amplitude in the plot appears lower than it
actually is (this effect can be seen on the TA plot from May 27th).

The same scheme could be repeated for 21, 22, 23 UTC etc (?..).
If more stations participate, the slot times and gaps could be reduced down
to 3 minutes (or 90 seconds if the intervals were strictly synchronized).

For un-coordinated "occasional" transmissions, here a first suggestion for a
kind of schedule. It may look strange and certainly needs to improved:
A = southern G (the big guns please lead the parade :)
B = north+west G, GM, GW, EI, GI
C = ON, PA, DL
D = F, HB9, I, OE, OK, OM
E = OZ, SM, OH
F = reserved for 'rare birds' and DX

The coordination of such a project should be done by someone else, because I
quite busy from other tasks at the moment.

Have fun SEEING your signal being detected in Portugal !

73's, Wolf DL4YHF.

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