[600MRG] Near-vertical sky wave downloadable WSPR data: WD2XSH/15 into W5EST

[James Hollander]

WSPR SNRs for WD2XSH/15 as received by W5EST last night are conveniently available today for download from the  WSPR database. This info is believed to indicate near-vertical sky wave reception when the SNRs exceed about -20dB.  

Open http://wsprnet.org/drupal/wsprnet/spotquery.  On database tab, set for MF, Last 24 hours, Call: WD2XSH/15, Reporter: W5EST, Sort By: Time Stamp.  You should see 137 spots. The SNR of each spot represents an average of the varying self-cancelled XSH/15 signal power over its 2-minute WSPR time slot. 

If you are interested in an what appears to be an example of 630m ionosphere effects, last night's data is most conveniently available to you today.  After today, you can less conveniently access last night's 1/29/15 info during the next two weeks by appropriately querying the WSPR database. 

W5EST is 10 miles from WD2XSH/15 in central Arkansas.  Slanting twinlead at W5EST picks up common mode XSH/15 signal and also conveys differential mode XSH/15 signal from an attic doublet antenna via a canceller circuit to a G33DDC SDR and wspr decoder on the PC. The homebrew canceller circuit was adjusted the previous afternoon to cancel WSPR ground wave by about 30dB by nulling the common mode signal against the differential mode signal to deliver -25dB WSPR SNR or less for WD2XSH/15.  Then the receiving setup was run from 1932Z through the night and into the next morning until 1448Z with no change in the canceller adjustments.   WSPR SNR departures of WD2XSH/15 at least 6dB from the null appear to represent near-vertical sky wave returns.

Contact me direct at mrsocion at aol.com if you want more details, have comments or critique, or want to discuss your analysis of this information.     --   73,  Jim H  W5EST