> house---choke just outside house---ground coax shield after choke---long
> coax run on/in GND---choke---ground coax shield near antenna mast
> base---up---active antenna.
> The idea is to make the shield of the long coax run "cold", at "soil
> potential" RF-wise so to speak, and the second choke + GND at the
> antenna base helps even more by making the antenna "see" its local GND only.
That is only valid for higher frequencies.
For 10..200 kHz chokes become less effective, I learned it the hard way. The
only solution was a 1:1 transformer at the shack, that effectively made VLF
noise free, because it interrupts the noise current on the coax screen.
Also Rx on other computers are connected via a separate 1:1 winding to prevent
noise current injection from those.
Make sure the hot-end of a winding does not sit on the ground-end of the other
winding, that had increased noise on shortwave and higher
Lasse, I just compared your antenna against my beverage and I do see a sweeper
running from 60..100 Khz, the same that I see here for many days. Does anyone
know who that is? Sweeping that low is very unsual.
Jurgen Bartels Suellwarden, N. Germany
Ant. hor: 29-45MHz 7-el, 45-87MHz 11-el, FM 15.11, Band-3:13-el, UHF:48-el
TV: Winradio G305 / Fly2000 + video noise filter & variable IF BW
FM: Downconverter + Perseus + Speclab as WFM demod.
MW: 30 x 4m EWE 320° with JB-terminator, Winradio & Perseus