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Old August 26th 04, 12:44 AM
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Default ANTENNA TWINLEAD FEEDER

hello to all
from Gilles ve2lx

1 st past ever on this group

I just install temporary an invert dipole feeded with tv twinlead 300 ohm

actually I have no RF interferences from 160 to 12 m (but only low on 10 m
but no more usable anyway ) compare to my end fed I had 2 month ago...!

antenna length is 66 ft or 33 ft each side and feeder length about 48
ft...the dipole is parralele to the back of the 20 appartement's house and
the full SFC remote coupler or tuner ( builted only for wire tuning ) is on
my back galery 8 ft from radio on 3 rd floor a little above hand rail...!

(((......I found 75 ohm twin lead...... )))

and ( I would like to use it instead ) for10 to 80 and 160 m ( actually I
do it with 300 ohm twin lead accepting low efficiency on 160 m and perhaps
on 80 m but it is ok.

my target
1...is to have as much efficiency as I can for all bands use primaly on 40
and 20 m ( reason for 66 ft )
2...at 75 ohm on 80 meter there will be much less SWR ( like 1/30: OR MORE
WITH 300 OHM on 80 m ) due to unmatch compare to 300 ohm
3...there will be better energy transfer because dipole is + or - 75 ohms
and feeder also and the tuner will search less value to match then therefore
les chance of RF problem radiations form feeder ( les larger ) and so on
4...feeder length will have less effect at 75 ohm on a all bands
consideration...?

is this thinking correct

wishing to ear from amateurs with good experience with balance or twin lead
feeder


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