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Old August 14th 06, 03:53 PM posted to rec.radio.amateur.antenna
Lee Lee is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 36
Default QFH Antenna and 72ohm TV Coax


"Jerry Martes" wrote in message
news:hU%Dg.12256$hH1.9718@trnddc08...

"Lee" wrote in message
k...
I`m building a QFH NOAA weathersat antenna and wish to use low loss t/v
coax
which is
72ohm; but is more manageable and less lossy at VHF than the 50ohm RG58
specified
over a 100ft run!.... ( RF pre-amps aint cheap! ).......

What are the pros and cons... can i use CT100 72/75ohm..... i believe i
can
but, will the impedence affect
the 4 turn choke ????...

Thanks.

Lee......de G6ZSG.....


Hi Lee

There are alot of affordable amplifiers designed for TV that you could

use
at the base of your QFH. You might consider building your owm amplifier

to
fit in the base of the QFH.
I wouldnt recomend the use of a pre-amp at the antenna for NOAA satelite
station. They often cause more problems than they solve.
All Electronics has alot of ferrite tubes that can be used to fit over

the
coax so you wouldnt need the "4 turn choke".


`4 turn Choke Balun`.....typo....


Jerry


Thanks Jerry, i`ll give it some thought as i`m right under some pmr towers
which breaks through a little from 150megs pagers and a preamp may worsen
things...

Lee....de G6ZSG....