Did you check the feedline losses?
What kind of "twinlead" did you use?
300 ohm Radio Shack TV line?
Or something better with less loss.
What kind of tuner were you using?
How do you know it was adjusted for
acceptable power transfer?
How high was the wire antenna?
Did you check it's performance in ALL directions?
Do you know which directions the Peaks and Nulls
of the antenna pattern coincided with?
A 50 ft centerfed wire antenna is close to two
half waves in phase on 15M which should produce
a figure 8 pattern, approximately 50 degrees wide,
with DEEP NULLS off the ends and a very high
feed impedance. The best feed system would be
a GOOD low loss open wire line and a balanced
tuner. A Johnson Matchbox and 450 ohm ladderline
should provide acceptable performance.
I think you were premature to condemn the
ANTENNA as a dog. Perhaps there were
other problems or circumstances that
were responsible for your observations.
You may have had SYSTEM problems
that had nothing to do with the antenna.
'Mystery twinlead and questionable baluns'
are highly suspect.
Tom N4KG
On Tue, 28 Aug 2001 Tom Osborne <w7why@harborside.com> writes:
>
>
> HI TT'ians.
>
> I had quite an experience today. I've been playing around,
> trying to figure some sort of antenna to use for a 2nd radio
> antenna.
> Today I put up a G5RV (sorta). I made it about 25 feet long on
> each leg. Fed it with half the length of twin lead (sorta) that
> a regular G5RV would use. Came in the shack and the first band I
> tried was 15. Couldn't believe my eyes, but the SWR was FLAT!!
> Got all excited and started tuning around the band. Heard a DL
> coming in but not too strong. I switched to my 20 meter beam and
> low and behold, he was louder on that than the (sorta) G5RV. I
> switched to the 40 meter verticals and he was louder on that
> too. I could tune the SWR down on other bands, but boy, what a
> dog of an antenna it was! It came down and went into the scrap
> pile. Guess it goes to showya that SWR don't mean diddly
> sometimes. 73
> Tom W7WHY
>
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