It would be interesting to see the results of a fully double blind scientifically reproducible test done with traceable engineering quality test equipment on a closed pedestrian mobile track.
NU6T On Sun, Sep 25, 2022, 12:19 PM David Gilbert <[email protected]> wrote: > > To be a proper comparison, the AX1 needs to be out it the clear away > from anything else, preferable at a height that allows the counterpoise > to be hanging straight down with the end maybe a foot or two off the > ground. Measurements should be with the AX1 at the same height above > the ground without and without the counterpoise. Ideally a KX2 or > similar rig should used, be battery powered (with very short leads if > external), no coax, and no body contact to the source of RF. Signal > reports should be in microvolts ... the number of contacts isn't really > useful and neither is SNR if the readings are taken over a lengthy > period of time. > > If I can get my hands on an AX1, I plan to either climb a tree or set up > a tall fiberglass step ladder for the AX1 as far away line of sight from > my home as practical. I'd use my KX2 for the signal source, using the > Tune function to put out RF without touching the KX2. Near my home I'd > set up the portable vertical antenna I described in an earlier post, and > feed that to my K3 set to read microvolts. I'd operate the AX1 (with > and without counterpoise wire) and any other antenna for comparison, and > have a friend record the microvolts from the K3 as a blind test. > > I would use the tuner in the KX2 to simulate actual use, but that would > of course introduce a variable for possibly different amounts of loss in > the tuner depending upon the load. I don't see a good way to avoid that. > > 73, > Dave AB7E > > > > On 9/25/2022 7:06 AM, Ron Gruner wrote: > > I've just run two tests of my WSPR/AX-1 set-up with and without a > > counterpoise. Each test ran 24 hours over the last couple of days. Here > are > > the results: > > > > COUNTERPOISE? > > YES NO > > ------- ------- > > Total Contacts 152 129 > > Maximum Distance (km) 15,720 17,276 > > Median Distance 2,137 1,823 > > Median SpotQ 446 398 > > > > Where SpotQ = Kilometers / [(2 Watts x (SNR in DB + 36))/36) ] > > > > The WSPR circuit's ground and SMA connectors are apparently providing > > enough of a counterpoise to propagate a respectable signal. > > > > Here's a close-up of the rig with no counterpoise: > > https://gruner.com/k4rhg/wspr_ax-1_nocounterpoise.png > > > > 73, > > Ron Gruner > > K4RHG > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:[email protected] > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to [email protected] > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
