[Towertalk] GAO Challenger DX

Chuck Counselman ccc@space.mit.edu
Mon, 7 Oct 2002 15:27:00 -0400


Billy Cox <aa4nu@ix.netcom.com> has complained that I have not 
compared a 1/2w horizontal dipole to a 1/2w vertical for f = 3.5 MHz, 
so here is the result of that comparison.

NEC-4 says, for

*  f = 3.5 MHz;

*  vertical dipole top height = 141 ft (43 m) and bottom height = 2 m;

*  my New England ground (see my previous post); and

*  elevation angle = 7.5 degrees

       Antenna      | Gain (dBi)
       -------------+-----------
                    |
       Vertical     |   -4.7
                    |
       Horiz. dipole|   +0.7  <-- better than the vertical by 5.4 dB.
       at 141 ft.   |                                         ^^^^^^
       (broadside)  |


73 de Chuck, W1HIS