[Skimmertalk] SNR Measurements

[Pete Smith]

Wow, Rick - those are startling.  I run my SDR-IQ on my main arrays all the 
time here, and I share your impression that signals rarely exceed 50 dB 
SNR, even on the low bands.  I know your antennas are good, but I would not 
expect 100 dB differences.  I wonder if perhaps the SDR-IQ was clipping, 
and that caused some of these incredible numbers - I'm copying Alex in the 
hope that he may have some ideas.

73, Pete

At 08:50 AM 12/11/2008, Rick Walker wrote:
>Pete,
>
>Since there has been a significant discussion on the SNR parameter, I
>thought I would share some of the startling values I observed in this past
>CQWW.  The information is provided below.  I just pulled a few off the top
>of the list, but there were 1,100 different telnet spots during the contest
>generated from my skimmers (from both 20M and 40M) where the SNR was 100 dB
>or greater.  I don't normally see SNR values greater than around 50 dB or so
>during normal operation, so I was curious about this result.  I normally
>have the SDR-IQ receivers connected to a small RX-only antenna, but for this
>contest I had them connected into my main antenna arrays.  Even still, these
>values seem excessive to me...  :-)
>
>Any others note curious results like this?
>
>73,
>
>Rick
>K4TD
>
>
>FREQ (kHz)      CALL            SNR (dB)        SPEED (WPM)     RUN/S&P TIME
>(Z)
>14030.9 9A7A            174             32              CQ
>1253Z
>14020.3 VA7RN           174             27              CQ
>2125Z
>14069.2 YL7A            166             32              CQ
>1254Z
>14024.7 D4C             161             35
>1934Z
>14030.7 EA1OS           161             27              CQ
>1745Z
>14009.8 TM6M            159             34              CQ
>1303Z
>
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