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Old October 17th 05, 08:32 PM
Steve Nosko
 
Posts: n/a
Default Doublet Antenna question

No time to read all the other posts, but in short...


You are proposing a slightly shorter than 1/2 wave dipole for 75. This
should be no problem as it will have a little capacitive reactance and a
tuner should handle it.

The G5RV is pretty much the same thing, except it has some feed line
gymnastics to get a "fairly good" (50 ohm) match on many bands. This is
nothing more than an "antenna tuner in feed line" which doesn't require a
knob rather than one in a box which does. (:-)

My 40M dipole works on 30M as a slightly LONG dipole. [[ It also works on
75 as a really short one, but not too good]]

73, Steve, K,9.D;C'I


"Ed" wrote in message
. 93.175...
).

It turns out that it becomes quite challenging to implement an
efficient feed system (especially over a wide frequency range) where
the dipole is less than about 35% of a wavelength at the lowest
frequency.


Yes, my 100 foot length would be about 42% ofthe wavelength of my
lowest operating band, 75M.... perhaps it wouldn't be any problem for my
cheap MFJ balanced line tuner to feed it?

I appreciate your comments. I'm off shortly to study the website you
pointed me to. Thanks.


Ed K7AAT