The SWR is high, the resistive part of the impedance is very low and the
reactive part is very high. The high SWR makes the losses in the coax
higher, but at 160m the losses are very low to begin with so the
increase isn't so wild.
Likely the loss in most tuners feeding the 43' vertical through a short
coax is a lot more than 50% (3 dB) probably more like 90% (10 dB).
On 8/16/2010 5:48 PM, Richards wrote:
> Not arguing... but how do we know that? So much of the literature
> claims that impedance is either way high or way low, and SWR is way
> wacky, and, therefore, there are HUGE losses in the coax... Your
> comment is more encouraging.
>
> Using a coax loss measurement program one finds on the Antenna Book CD
> Disk, it seems like it is 1.5 dB to 1.8 dB on 160 meters (less on
> higher bands.)
> This does not comport with much of the literature on these antennas.
>
> Can you embellish your position any? I am very curious. (Again... not
> arguing, just asking as it IS rather more optimistic than some others
> have indicated.)
>
> And yes... you identified ANOTHER problem with the description. Good eye.
>
>
You do have to adjust that coax transformer's length depending on the
velocity factor of the coax that depends on the insulation density if
foamed.
73, Jerry, K0CQ
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