>Your compromise preserves 80M without retapping the coil, I guess, but
>the result is still an inverted L with only 27' or so of vertical, a
>small improvement over the inverted L using the Hytower MK-160A add-on
>that preserves 80, 40, 20, all the bands.
The 27' feet of vertical is much better than squeezing the high current
portion of the vertical antenna (the feed point) into a coil at the base. The
MK-160 out performs the base loading coil in two ways. It solves the
high voltage arc over problem of the base loaded version. It uncomprimises
the high current section of the 1/4 wave antenna.
> I've never heard of the
>base insulators arcing over. They're at a low voltage point so I don't
>think that's a problem. However, the insulators at the top tower
>section are at a high voltage point and, Hygain recommends running only
>100 watts to the Hytower on 160M. I live in a very windy area and have
>never had any problems with the mechanical strength of the aluminum
>tubing section.
>I think the Hytower is an excellent antenna on 40 and 80, and can be
>pretty good on 160 as a base loaded vertical. You're right, there's no
>easy way to top load the Hytower that I know of.
The inverted "L" is a top loaded vertical. The top section makes it electrically
1/4 wave long.
>I guess the Hytower is a linearly loaded antenna with the 24' tower
>section, and 24' 80M wire and 26' tubing above it fed in parallel. Is
>that your understanding? Can anyone help me here? I'm not sure I
>understand the linear loading, if indeed it is that. If I ever get
>time, I'll try to model it on YO.
The Hytower is a quarter wave vertical on 80/40/20/15/10 meters. The stubs
just provide individual decoupling for each band. The tower is used as a
radiator
for all bands except 80. The 80 meter vertical is comprised of the wire and
the top spike. If you add the MK-160, the tower is used as the vertical section
of an inverted "L". The 40 meter trap isolates the top half of the "L" from the
40 meter portion of the Hytower.
>I have considered adding an 8' section of tower to increase the total
>height to 60'. I think it would perform better on 160M, but am not
>sure I would be able to get it to resonate on other bands?
I found at VP5JM's, I had to add a small coil in the center wire to lower the
frequency to the CW band and about half of the was still used to bring it
into the phone DX window. It was about 10 turns of #12 wire on 3 or 4 inch
PVC. I did pretty with this on several trips and the '96 ARRL DX CW on
160 meters.
73, K8Joe"Palooka"
K8JP, K8JP/VA2, VP5/K8JP, VP5JP, ex-K8HKM, ex-KN8HKM
Secretary, NIDXA
Diver
palooka@pyrotechnics.com
snail mail:
Joe Pontek, K8JP
P. O. Box 59573
Schaumburg, IL 60159-0573
(847) 885-8871 (home)
(847) 519-7420 (work)
(847) 619-3250 (FAX)
U.S.A.
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