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Just a note,
The power on 500 is being reported as
ERP due to the problems with antenna efficiency ... as for low
power I have seen Rick ON7T decode signals from my
station with round 250 mW feed to the Ae ...
G ..
Sent: Sunday, November 08, 2009 10:36 PM
Subject: Re: LF: Re: WSPR
In addition to what James has said.
Use of the WSPR site more fully can eliminate a lot of the uncertainties
being discussed
If more stations use the WSPR website/database for reporting then more
consistency is obtained, or at least the possibility of allowing some
calculation and estimates on what is reported.
When reporting then you are asked to keep your tx power low and to enter
your TX power in the set up window ,so that we all know what it is. Also on the
site there is a section where you can describe your station
parameters.
peter G8AFN
2009/11/8 James Moritz <[email protected]>
Dear Mal, LF Group,
----- Original Message -----
From: "mal hamilton" <[email protected]>
WSPR reports amongst stns indicate reception reports
usually minus dB. Most of these stations are usually PLUS dB >with me or
very close to that figure.
So what does that
prove.
It proves the SNR is higher at the output of
your receiver than it is at whatever other stations you are talking about
I would say it depends on the RX antenna and not
necessarily propagation.
So how then does the signal
reach the RX antenna? Radio wave propagation has always to be involved
somewhere!
A large antenna yields better results than a small loop or
active whip.
Not if the small loop or whip are
designed to achieve adequate SNR at the frequency of interest.
When I switch from my 1/4 wave inv L for 500 khz to a
smaller 40 m resonated loop for 500 the signals then do go >down to a
minus db figure.
So what is all this all ABOUT
?
It is probably about the different directional
patterns of the vertical and loop antennas, resulting in different signal and
noise levels at the receiver, and therefore different values of SNR. Or maybe
your loop just doesn't work very well.
There is also the TX pwr to consider. Two transmitters
from the same location one using QRO and the other QRP will be >received
at different levels at a specified RX location. There is a lot of
misrepresentation and misleading information by >WSPR
operator
This applies also to CW or any other type
of signal. It is a bit rich for someone so shy of giving figures for his TX
power to suggest others are being misleading...
A trace of the signal is visible long before a decode
takes place, therefore why not use QRS in the first
place.
Because a trace of signal is just that; a
decoded WSPR signal contains station ID, location, and power information,
making it much more useful, without the operator actually having to watch a
computer screen 24 hours a day.
Cheers, Jim Moritz
73 de M0BMU
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