LF: NagsHead Report #7: Estimating S/N Ratios]
Wed, 27 Jan 1999 07:22:38 -0500
> Frank Gentges makes a number of interesting suggestions, including
> automeated LF monitoring.
> > LF broadcast signal strength strip chart level recordings could be
> > of value in identifying when propagation is at a peak and a receiving
> > trip should be launched. Since the LF broadcast stations are so
> > powerful the level monitoring setup does not have to be too special
> > in terms of siting and antennas. More sophisticated computer
> > monitoring of these signals with a computer driven receiver could
> > gather more complete data.
> Over here in theUK, the Cave Radio and Electronics Group has done a
> certain amount of this monitoring to look for free frequencies for
> cave radios. When I say 'the Group', it has actually been John
> Rabson G3PAI who has done the work. His equipment scanned from (I
> think) about 30kHz to about 200kHz in steps of the order of 1kHz,
> Some results, with outlines of the equipment, are reported in the
> following issues of the CREG Journal:
> #29, pp.19-20, Sept 1997, "LF spectrum surveys - a review"
> #31. pp.26-27, Mar 1998, "From luggable to portable - improvements in
> LF spectrum survey apparatus"
> All have J. Rabson as author.
> I can't speak for John, but if anyone wanted to set up such a
> monitoring system I suspect he might be willing to pass his software
> Frank - if you email me with a snail-mail address I'll post you
> copies of those two papers, if you wish.
> Chris Trayner G4OKW