No we didn't measure the VSWR. The aircraft was supplied with the copper
dipole bonded into the tail per the Europa manual. All we did was bond the
Bob Archer aerial into the fuselage. Yes, Bob's aerial is a common J-
Matched dipole - but it does take the hassle out of installation for those
who don't have friends with VSWR meters!
Tony
-----Original Message-----
From: owner-europa@aztec.houxou.com
Subject: Re: Bob Archer - an endorsement
I won't disagree that a mfr'd antenna may be superior to a cobbled
copper-tape affair, but I suspect that the difference is substantially
in defects in the copper tape setup. Did you by chance compare the
VSWR on both antennas?
On my copper tape antenna, and starting with Jim Weir's recommended
length, the VSWR meter had me trimming a couple inches, probably due
to some odd bends that Weir says are OK. It came out just slightly
better in VSWR than a new, commercial, VHF comm broad-band whip that I
compared it to.
An engineer friend of mine (who designed antennas for the co. he
worked for) tells me that antenna performance is strictly VSWR and
optimum radiating pattern, which can produce some "gain," but not much
available there if you need a 360-deg pattern. IOW, he says nothing
in Archer's (or anybody's) design can produce an order-of-magnitude
performance difference given proper tuning of each. He says also that
the Archer sounds like just a common "J-matched dipole." These maybe
have a more efficient balun, but he questioned its being made of
aluminum (it is, right?), which has long-term performance problems
over copper, whose surface corrosion is not detrimental.
Regards,
Fred F., A063, N3EU
Tony Krzyzewski wrote:
>
> I just took ZK-UBD for its first flight after replacing the copper dipole
> aerial with a Bob Archer aerial. The difference in reception can only be
> described as dramatic. The reception distance from out local field has
been
> increased over 10 fold for a start. In addition, one of the southern
> approaches along the coast is normally blanketed by the hills, for the
first
> time in any aircraft I have flown I had full reception all the way in.
>
> I'd consider the Bob Archer com aerial a mandatory fit for the Europa now.
>
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