[digitalradio] Re: One way propogation?
The RF transmitted signal changes polarization repeatedly as it is refracted between the ionosphere and ground/ocean surface. A horizontally polarized signal radiated from a dipole can arrive at the receiver end with a polarization that is horizontal, vertical and even elliptical. Therefore antenna polarization reciprocity is not necessary on MF and HF frequencies to make contacts. 73 & GUD DX, Thomas F. Giella, NZ4O Lakeland, FL, USA n...@arrl.net LF/MF/HF/VHF/UHF Frequency Radiowave Propagation Email Reflector: http://lists.contesting.com/mailman/listinfo/spaceweather NZ4O Daily Solar Space Weather & Geomagnetic Data Archive: http://www.kn4lf.com/kn4lf5.htm NZ4O Daily LF/MF/HF/6M Frequency Radiowave Propagation Forecast & Archive: http://www.kn4lf.com/kn4lf6.htm NZ4O 160 Meter Radio Propagation Theory Notes: http://www.kn4lf.com/kn4lf8.htm NZ4O Solar Cycle 24 Forecast Discussion & Archive: http://www.kn4lf.com/kn4lf72.htm No virus found in this outgoing message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.39/2134 - Release Date: 05/25/09 18:14:00
[digitalradio] Re: One way propogation?
If everyone is running the same antenna oriented the same way then it ought to be reciprocal paths. However that is rarely the case and it would seem not too unusual that forward and reverse paths are often different, sometimes substantially so. I'm always amazed how many verticals I can work off my rather low dipole :-) 73, Scott k*b*l*0*0*q --- In digitalradio@yahoogroups.com, Vlad UA6JD wrote: > > Few days ago I copy Javier , KH2QII/KH6 , on 14076 JT65a > with peak -16dB (!) - he report that using 30 watts & vertical. > I try call him with 100 watts and 6 el YAGI and he told me that no > copy me. > Today I am CQing on 14076 and few stations on West Coast reports that > copy me with no less then -20dB - but on my SpectJT no any the most > fine lines execpt one from N9DSJ with peak -10dB. I am running today > same 6 el YAGI beaming USA over North Pole and 50 watts. > > > > -- > 73 Vlad UA6JD >
[digitalradio] Re: One way propogation?
--- In digitalradio@yahoogroups.com, Vlad UA6JD wrote: > > Few days ago I copy Javier , KH2QII/KH6 , on 14076 JT65a > with peak -16dB (!) - he report that using 30 watts & vertical. > I try call him with 100 watts and 6 el YAGI and he told me that no > copy me. > Today I am CQing on 14076 and few stations on West Coast reports that > copy me with no less then -20dB - but on my SpectJT no any the most > fine lines execpt one from N9DSJ with peak -10dB. I am running today > same 6 el YAGI beaming USA over North Pole and 50 watts. > > > > -- > 73 Vlad UA6JD > Vlad, nice to work you the other morning, thank you. I wonder what software Javier was using? If he was using JT65A-HF test version, there have been some bugs where the SNR level has been "odd" compared to signals heard with human ears. Some STRONG signals do no decode well with JT65A. Andy K3UK
