[Elecraft] wire for random wire antenna using kx3

[John Oppenheimer]

On 12/17/18 1:58 PM, Jim Brown wrote:
> In order of loss at dB/100 ft at 10 MHz from low to high, the 
> Teflon #12 is lowest at 0.94dB, then RG400 at 1.22 dB (about the same as 
> RG58), then #12 THHN at 1.34 dB. #12 or #10 enameled copper had the 
> greatest loss, 2.4 dB/100 ft.

Hi Jim,

Two parallel transmission line is the easiest of all to evaluate using a
RF resistance table and knowing the impedance of the line.
http://ve3efc.ca/wireohms.htm

The wire loss is dB = 10 * log10((Zo + WireR)/Zo)

Assuming Zo=100 for the #12 Teflon and THHN. R at 10 MHz = 4.24/100 =
8.48/200.

Wire dB = 10 * log10(108.48 / 100) = 0.35 dB

Using the two values above at 10 MHz, 0.94 and 1.34, the dielectric loss
is 0.59 dB and 1 dB. The dielectric loss is about two and three times
the wire loss.

John KN5L