Hi Bill The resonance element reradiate noise and also the signal. If you think about why a yagi works, all elements reradiate the signal from the driven elements, but what about on reception, . It is the same. All resonate elements reradiate. Any resonant structure does the same.
Here detuning the TX antenna droops the noise by 2 S units on the RX noise. >> So, why am I not hearing this noise many are experiencing? << Noise does no add because it is incoherent, so when you remove one layer you hear start hearing the second layer, there is always noise. But you can hear only to predominant noise the strong one. Detuning a tower is no easy, NX4D 90 FT vertical with top hat is insulated from the ground, Doug was using one vacuum relay to disconnect the tower from the feed line, Doug did it in 2007 however last year he decided to tune a wire tapped 30 FT on the tower, the wire was there because he used to shunt feed the tower. Doug used a capacitor to tune the wire like W8JI explain on his website, guess what, 2 S units down on the noise floor. Now is WF has a really deep null on the sides and RX is much better. On Doug's case some capacitance or something was not right, end even using a detuning relay and floating the tower was not enough to detune the structure, How far the tower can detune your RX antenna,? Well it is easy to see it using EZNEC, one wave far is not enough and on 160m it is over 500ft away. Regards Jose Carlos N4IS ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2180 / Virus Database: 2433/5075 - Release Date: 06/17/12 _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
