>Checking the TT webb page, I find that their G5RV requires 70ft of coax
>minimum. Why is this? I've seen this somewhere before but never gotten a
>technical explanation for it. It would seem to increase loss (a lot)
>especially if RG-58 is used as mentioned! But perhaps this is the plan.
>Maybe they want higher loss so the swr will appear lower.
1. The G5RV is not really a <resonant> antenna.
2. Anytime the antenna is not at resonance, the
the impedance will vary along the length of
the feedline.
3. The 70' is most likely one of the best "over-
all" choices to keep things as close to 50 ohms
as possible. You must remember that the G5RV
is at best ONLY a "compromise" antenna.
4. Oh yes, the longer the feedline, the lower the
SWR will "appear" to be, especially with coax
fed systems.
...AD4YH
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