On 22 Apr 2006 19:59:17 -0700, "RHF"
wrote:

Dale [W4OP],

"Since the vertical angle of radiation is so narrow,
about 8 degrees toward the horizon, it usually out
performs 5/8 wave or groundplane type construction
due to their much higher angle of radiation. It is
estimated that the Slim Jim has about 6dB gain
over a 5/8 wave antenna due to the extreme
low angle of radiation."

"Editor's Note: There are many gain figures quoted
for this antenna and also various descriptions of the
actual type of antenna on various websites. Some
have even stated that, "In fact I found it outperformed
a 1/2wave over 1/2wave over 1/2wave colinea"

For many of the design applications as a Transmitting
Antenna in the 2-3 Meter range; and a receiving Antenna
for the FM Band. This Slim Jim Antenna is effectively a
small space Antenna that performs well for it's size and
when compared to the greater space requirements of
other Antennas.

iane ~ RHF
.
.
. .
.
RHF,
This is what is claimed on the website though it is indeed not a true
representation of how the antenna performs. They perform no better
and no worse than any other half-wave antenna, besides look at how
they phrase it "estimated 6dB gain over...." which says that is not
calculated, tested or proven. If somebody built a slim-jim (j-pole)
that outperformed a colinear with multiple half-wave sections I'd look
at how each antenna was installed (height, clear of buildings etc) the
type of cable used (well we used hard-line with the slim-jim and 200
feet of RG-174 with the colinear) and wether or not that colinear was
properly constructed tuned. Hey, I'm not trying to rain on your
parade or be the guy who has to tell you that Santa Claus & The Tooth
Fairy or the Easter Bunny don't really exist - but in the end the
slim-jim/j-pole just doesn't perform as claimed on the website you
have visited.

Howard