LF: Re: HB9ASB... SNR of DCF39

["James Moritz" <james.moritz@btopenworld.com>]

Dear Stefan, Minto, LF Group,

No TX this evening here, I'm afraid, but I took the opportunity to make 
rough measurements of the field strengths of G3KEV (12uV/m), DK7FC (1.9uV/m) 
and HB9ASB (0.7uV/m) - see the attached screen capture.
As you can see, these are all "O" copy signals here. KEV is quite a strong 
audible signal here as usual - DK7FC and HB9ASB look a bit weaker than they 
actually were - this screenshot was taken with my loop oriented approx. N-S 
to measure Mal's FS; with the loop oriented E-W Stefan and Toni were both 
several dB stronger. The QRN level was fairly low here for the time of year, 
and the band noise was dominated by Loran C with the loop aimed N-S, and 
sidebands from DCF39 with the loop E-W.
Earlier, I repeated PA3BCA's signal-to-noise measurement on DCF39 - The SNR 
of DCF39 was about 82dB with the 0.5Hz FFT noise bandwidth. My location 
IO91vr is a bit further from DCF39, so I would expect the SNR in PA to be a 
few dB higher under similar conditions. The field strength of DCF39 was 
about 3mV/m (several dB higher than the daytime level I have measured in the 
past), making the noise floor about 0.24uV/m in 0.5Hz.
Cheers, Jim Moritz
73 de M0BMU

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