Topband: Modeling the proverbial "vertical on a beach"

[Juan EA5RS]

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 at greenrover.demon.co.uk [mailto:paul_group at greenrover.demon.co.uk] 
Enviado el: domingo, 17 de agosto de 2014 9:10
Para: n7rt at cox.net
CC: ea5rs at ono.com; hsvdds at juno.com; Topband at Contesting.com; w8ji at w8ji.com
Asunto: Re: Topband: Modeling the proverbial "vertical on a beach"



------- Original message -------
> From: Hardy Landskov <n7rt at cox.net>
> To: ea5rs at ono.com, hsvdds at juno.com
> Cc: Topband at Contesting.com, w8ji at 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 ---