Jimmy, Think of it this way...if the feed point resistance of your antenna is 12ohms, "a low VSWR across the band", and fed with a 50 ohm transmission line, you have the equivalent of putting a 40 ohm resistor from your antenna connection to ground. This is all wasted power except for a few percent that is radiated skyward.
73, Herb Schoenbohm, KV4FZ >> The radiation resistance of your antenna is 12 ohms. >> >> The 1.5:1 VSWR tells us the base resistance is either 33 or 75 ohms. The >> ground loss resistance is either 21 or 63 ohms. The radiation efficiency is >> either 36 or 16 percent. >> >> The low VSWR over the band (1.8 to 2 MHz?) points to the base resistance >> being 75 ohms. >> >> Dave WX7G >> On Nov 30, 2011 1:28 PM, "james soto"<[email protected]> wrote: >> >>> Hello friends,I am experimenting with an inverted L for 160. the antenna >>> is about 132 ft long with about 45 to 50 ft vertical and the rest >>> horizontal.i have about 4 radials connected direct to the antenna and one >>> wire connecting to other radials that use to belong to another vertical >>> antenna not in use now. at this time i have work south ,central and north >>> america but i have not work any europeans as yet. the wsr is pretty ok 1.5 >>> across the band . i disconnect the ground from the antenna and i don see >>> any difference in swr at all. my question is do leaving the ground wire >>> disconnected from the ground rod improve the reception? any ideas are >>> wellcome. >>> >>> ps i also have a 1/2 wave dipole for 160 at 60 ft high and running in all >>> kind of shapes ( no space for long antennas) and my reception is better >>> with the inverted L. >>> >>> thanks and 73's >>> >>> de kp2bh / kp2dx jimmy >>> _______________________________________________ >>> _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
