The radiation resistance is 25 ohms. I estimate your base referred ground loss resistance to be 10 ohms. So, you should expect a VSWR of 1.4:1 fed directly with 50 ohm coax.
To obtain a better match you could place a shunt inductor (start with 4 uH) across the feedpoint but you will have to shorten the T wires a bit. Dave WX7G On Jan 25, 2012 12:28 PM, <[email protected]> wrote: > Hi Everyone, > > just finishing puting up a T Vertical (exactly in T shape) using 2 > supports at the ends. > > The vertical portion is 18m and the T is 17m to each side (34m total). > > I am laying radials from 20m - 40m (have about 20 right now). > > My question is regarding the feeding of the antenna, should it be > straight with 50 Ohm cable? Should I make some impedance transformer? > (I have FT240-61) that I could use. > > Thanks for help, getting ready here for CQ WW cw 160M. > > 73's Filipe CT1ILT aka CR6K > > _______________________________________________ > UR RST IS ... ... ..9 QSB QSB - hw? BK > _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
