Thank you for the reference Paul.
Regarding the quote by N4ZR stating:
"I had earlier understood that SNR was calculated in a relatively short
interval just before the spot was sent to the Telnet server. Turns out that
the calculation is based on data collected in the 50-Hz decoder channel for
about 45 seconds up to the moment when the spot is validated and forwarded to
the Telnet server"
I just rechecked with a copy of Skimmer v1.8 and a recorded audio snippet with
my call and found that is not the case with my setup, I cannot speak for
others.
With a clean Skimmer program start, it sent out a spot after two instances of
my callsign sent at 34 wpm, that is after less than three seconds of signal
sampling.
I repeated this same experiment five times, same behavior every time. Reported
SNRs varied from 19 dB to 22 dB. The input to the soundcard is the same
recorded audio signal.
73
-----Mensaje original-----
De: paul_group@greenrover.demon.co.uk
[mailto:paul_group@greenrover.demon.co.uk]
Enviado el: domingo, 17 de agosto de 2014 9:10
Para: n7rt@cox.net
CC: ea5rs@ono.com; hsvdds@juno.com; Topband@Contesting.com; w8ji@w8ji.com
Asunto: Re: Topband: Modeling the proverbial "vertical on a beach"
------- Original message -------
> From: Hardy Landskov <n7rt@cox.net>
> To: ea5rs@ono.com, hsvdds@juno.com
> Cc: Topband@Contesting.com, w8ji@w8ji.com
> Sent: 17.8.'14, 3:47
>
> Juan,
> Am I wrong to assume that skimmers are not calibrated? They should be
> calibrated to S-9=50 uV into 50 ohms at least to provide some kind of
> uniformity band-to-band and skimmer-to-kimmer. I don't know you guys
> tell me what's going on because I see these reports scrolling across
> my screen that make no sense......
> Hardy N7RT
>
Please take time to read the following page to assist your understanding of the
RBN snr report
http://reversebeacon.blogspot.co.uk/2014_03_01_archive.html
73 de Paul LA/GW8IZR
> ----- Original Message ---
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