That's right - the losses in good quality 600 Ohm open-wire line
operating with an SWR of, say 10:1, would be less than the losses in the
same length of matched RG213. The balance tips slightly the other way
for some of the commercial "450 Ohm" window lines.
Steve G3TXQ
On 05/05/2014 22:17, Hans Hammarquist via TowerTalk wrote:
Yes Dave,
You are right. I just find it "funny" that this relationship exist. Some hams may think that the
"reversed" impedance has nothing to do with "tuning".
I just wonder: You, and may with you say that it is most efficient to put the
tuner/match box/etc. as close to the antenna as possible. That is true if yoy
will get excessive loss due to the high SWR in the feeder between the
tuner/match box/etc. Now, if you have a really low loss feeder (like my ladder
feed) between the antenna and the tuner/match box/etc. and a maybe higher loss
coax (like something really cheap) between the tuner/match box/etc. and the
transmitter. You might then be better off (by some silly few fractions of a dB)
with the tuner/match box/etc. next to the transmitter.
This is just to make us think a little about that odd situation we normally
don't get in to.
Hans -N2JFS
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