[Elecraft] Folded Dipole Antennas

Mon Dec 8 11:15:01 2003

What impedance is the 0.5 dB measured into? A full wavelength antenna =
will present an impedance of a few thousand ohms. This is outside the =
desirable range for a 1:4 balun. Now on some bands the VSWR can be =
nearly 100:1. This is where the loss of even open line can climb to a dB =
or more.

This would make an interesting experiment to measure the actual losses =
on a typical center fed zepp.

   Dave WX7G

-----Original Message-----
From: George, W5YR [mailto:[email protected]]
Sent: Friday, December 05, 2003 4:12 PM
To: drcuthbert; [email protected]; [email protected];
[email protected]; [email protected]
Subject: Re: [Elecraft] Folded Dipole Antennas

Interesting . . . my tuner measures 0.5 dB loss on 20 meters and the 36 =
feet
of ladderline to the 20-meter EDZ surely doesn't add more than a =
fraction of
a dB more loss. Seems that a system like mine that displays "a few dB" =
of
loss would need some work.

George W5YR

----- Original Message -----=20
From: <[email protected]>
To: <[email protected]>; <[email protected]>; =
<[email protected]>;
<[email protected]>
Sent: Friday, December 05, 2003 4:12 PM
Subject: RE: [Elecraft] Folded Dipole Antennas

You won't measure the 800 ohm resistor as it is fed thru a 1:16 balun. =
The
cost of the resistive termination is 5 dB or so. About like turning a =
100
watt rig down to 30 watts. Not that bad unless one is trying to win
contests. Now contrast it to a comparable ladder line fed zepp with line =
and
tuner losses of possibly a few dB. Now there isn't that much difference.