|
Jay,
thanks for the
comments. Well honestly there hasn't been much change in the TX setup here, no
secret tricks and no "solid one watt" here.
About a month ago one of
the neighbour families had a 12 m fir tree chopped down in the vicinity of
my antenna, which has reduced losses and presumably also E-field
shunting a bit. The antenna losses are now about 22 ohms. I have
gained about a dB by reworking the matching between the class-D and
antenna, which increased the output from 250 to about 320 watts, producing
3.8 amps on an average day.
I did recently remeasure the effective height by
comparing received DCF-39 voltage against a small nonresonant loop, and still
got only 8.5 m (without the tree), ie 24 milliohm radiation resistance at
LF. Thus antenna efficiency is 0.11% and ERP is 0.64
W.
Regarding receive, I have tried to improve the
crossed loops by making them larger and higher. The increased bandwidth
has helped to stabilize the colours of my RDF system. I have then also
reinstalled the indoor goniometer configuration, which in combination with
the Marconi makes a rotatable cardioid with good F/B ratio.
Unfortunately there hasn't been much benefit in this as the SNR
performance of the loops is still rather mediocre, due to severe pickup
from DSL (the data uplink spectrum starts at 138 kHz) and power
lines.
Thanks for the continuous monitoring!
Best 73,
Markus (DF6NM)
Sent: Friday, November 23, 2012 1:33 PM
Subject: LF: T/A
Markus
'Best Of' from last night at http://www.w1vd.com/interestinggrab.html .
Would still like details on the big improvement in your signal this season.
Only minor improvements on the rx setup here so it must be on your
end. Hoping it isn't a 'trade secret' ;~)
Jay W1VD WD2XNS WE2XGR/2
----- Original Message -----
Sent: Thursday, November 22, 2012 5:04
PM
Subject: Re: LF: T/A
Jay, excellent! I'm glad we've got someone like
you looking from the other side of the water. Putting the "best of
last night" capture online is valuable, as most of us would have our
eyelids closed at the time...
Best 73,
Markus (DF6NM)
Sent: Thursday, November 22, 2012 1:23 PM
Subject: LF: T/A
Good signals from Stefan and Markus ... DST recovering
to about -27nT. Selected capture at
http://www.w1vd.com/grabber.html .
Fadeout just after 0700Z.
Jay W1VD WD2XNS WE2XGR/2
|
