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[TenTec] R-7000 Vertical Experience

To: <tentec@contesting.com>
Subject: [TenTec] R-7000 Vertical Experience
From: k8mn@clinet.fi (Dave Heil)
Date: Wed, 15 Oct 1997 19:42:23 +0100

In responding to K5XS's query regarding the off-topic vertical
discussion, let's be careful not to let our opinions get in the way of
facts.  I used an R-5 vertical as my only 12 and 17 Mtr antenna from
9L1US and for two of the three years I operated as A22MN.  I've had the
same antenna here in Helsinki for the past two years.  The traps can and
do work up to the manufacturer's ratings.  These ratings assume low SWR.
If you smoked a trap and informed Cushcraft, I'm sure they'd replace
them for you.  

If you're a traveling ham or can't put up yagis these "sans radials"
type vertical antennas work pretty efficiently and with plenty of low
angle radiation.

Dave Heil OH2/K8MN
downtown Helsinki

David Wright wrote:
> I concur.  I've used both the R-7 & R-7000.   Both are overrated on
> their power handling capabilities.   I've burned traps on both antennas
> with a  500w AL-80B.   On the R-7, the "black box" on the bottom of the
> antenna fried @ 100 watts!  Good SWR (1:1), 1/3 or less of the power
> rating, and the result was TVI galore (especially 40m @ 50+ watts!) and
> burnt up city.  Forget it.
> I hear the Hygain TH-77 will handle up to 2kw pep but I have no
> experience with it.  Force Antenna's make a vertical tri-bander that's
> small (5ft long) and handles full power.    I gave up and went back to
> big Yagi's and wires myself.   They work and handle all the power you
> can give them (Alpha 89).  GL and let us know how it works out for you.
> 73 de Dave KB6JOX

> >
> >   I use one for one year and half, I burned the 20m and 30m traps with only
> >an IC2KL (400W and the SWR < 2:1). Same problem with the R7000 at the club
> >station F5KPG but only the 20m trap burned (Yes burned all is black in the
> >trap!!! and SWR > infini). If you use it with less than 200W it is a good
> >antenna. But Cushcraft lies when they sell it for 1500W PEP.
> >   To stay in the topic, is anybody can give an idea to command my IC2KL
> >with my Omni 6 for the automatic band changing. With the Icom amplifier it
> >is just a pin with different tension depends of the band.
> >73 de Philippe - F6IFY
> >P.S.: Sorry for my poor english.
> >--

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