Hi Steve and all,
I suspect that these propagation peaks that last two hours
or more are accompanied by relatively stable phase delay.
If so, coherent detection using a carrier recovered by
e.g. an hour's integration should be feasible.
Is it known if the transmission from DBF39 is stable enough
to measure path delay changes? If it is, do you have a way
to record phase variations?
73,
Stewart KK7KA
----- Original Message -----
From: "Steve Dove" <[email protected]>
To: <[email protected]>
Sent: Wednesday, December 18, 2002 10:49 PM
Subject: Re: LF: M0BMU Jason Success!
Greetings,
Firstly, may I add my heartiest congratulations on this 'Jason' first, to
Jim, John and the conceivers and developers of the mode, especially
Alberto.
Quietly, in the hope of eventually turning this into something more
useful, I've been recording DBF39's strength using DL4YHF's
excellent Spectrum Lab software. Below is the take encompassing
last night's success. The most useful data column is the first, being
the peak detected signal. Following that are an on-frequency
average (within 1Hz bandwidth) and that of an adjacent 1Hz slice.
It is relative only, uncalibrated in absolute signal level as yet.
Empirically, anything bigger than about -26dB is ear'ole copy. Of
note is that a few hours later than John's reception, between 0400
and 0600, DBF reached a few dB louder. Indeed as big as I have on
record so far.
Again, well done!
Steve W3EEE
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