Dan, OK1DIG wrote:
"Should I transform from 75Ohm to 50Ohm on the separate receiving ant in
my IC-756? or just simply connect the ANT to the RCA socket ?"
Just simply connect it to the RCV ANT RCA jack on your IC-756. It will
work ok like that.
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>
"Does the mismatch have gerat influence on the overall receiving
performance ?"
You won't notice any difference between 50 and 75 Ohm line into your
IC-756.
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"I am considering to build a phaised two Beverages in one direction where
my space is limited, however I would like to use the Beverages for
multiband operation 80 to 40 m. Any suggestions on the spacing ?"
For zero side lobes, best broadside (side by side, no stagger) spacing
on 160m is about 100 meters. On 80m the best spacing is about 50 meters,
so I would space them 75 meters apart for the best compromise. Two
150-meter long phased Beverages will give approximately the same
performance as one 300-meter long Beverage. There will be small side
lobes on 80m, none on 160m.
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"Can I use the TV Ant splitters for the phaised Beverages ? If not what
is the phasing method for multiband operation ?"
No, you cannot use TV antenna splitters, Dan. They are designed for
VHF/UHF use and will not work at 160m and 80m.
For both 160m and 80m use, I would feed two broadside Beverages in phase
with two equal lengths of your 75-Ohm cable TV hardline coming to a
tee-connector, then 50-Ohm line to the receiver. There will be a slight
mismatch, but it should work ok. Make sure you use an impedance-matching
unun transformer (75-to-450 ohms) at the feedpoints of each Beverage.
73, de Earl, K6SE
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