[Elecraft] KX1 - We need to develop the ideal antenna

[Jack Smith]

10 years ago, I measured the loss of zip cord, with the results below. 
The measured results are based on a 17 ft length of zip cord.

Frequency 	Measured Loss (dB) 	Loss (dB)/100 ft
5 	0.4 	2.3
10 	0.6 	3.5
15 	0.8 	4.6
20 	0.95 	5.5
25 	1.2 	6.9
30 	1.4 	8.1


For comparison, RG-58 is spec'd at 1.4 dB/100 ft at 10 MHz and RG-178 at 
3.3 dB/100 ft.  So, zip cord is about as good (or bad) as RG-174 at 10 MHz.

I've significantly improved my measurement ability since then and should 
revisit the subject.

Jack K8ZOA



On 5/16/2011 12:02 PM, Dale Putnam wrote:
> Zip cord, at 50 - 72 ohm or so impedance, is a whole lot closer to the center fed impedance of a "close to the ground" dipole.
> Makes a fair amount of sense, to use it for feedline, clear down to the rig, when the rig has a balanced output.. or to the balanced to unbalanced, 1 to 1 ratio apparatus. And with a stranded, larger than RG-58 or RG-59 coax center, it won't have any additional I-R loss than that coax, and our HF freq. And of course, making the distinction that we are talking about a single band dipole... not a multiband, center fed with what ever the tx is dialed to balanced antenna.
>
> --... ...-- Dale - WC7S in Wy
>
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