A lot of the older Cuschraft VHF antennas that had those trigon ( as they
called them ) reflectors had issues with elements falling off due to
vibration in many cases. I would think that idea that they are weak at the
attachment point is probably right. Would be nice to find some new way of
dancin' that's for sure. That antenna probably gets to singing in the wind
and the vibration ( and possibly the BIRDS ) due those elements no good at
all. - Mike
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of RLVZ@aol.com
Sent: Monday, February 08, 2010 10:16 PM
To: ve5ra@sasktel.net; towertalk@contesting.com
Subject: [TowerTalk] XM-240 Shorty-Forty: X-Hat Modification
Hi Doung & all,
In my original post, I stated that some of my "X-Hat rods were falling
off" so I'd like to lengthen the element and eliminate the X-Hat rods.
A better description would have been I've had some "X-Hat rods breaking
off". I had the new XM-240 in the air for less than a month and one X-Hat
rod broke in two and fell to the ground. I dropped the antenna and
replaced
the broken X-Hat and put the antenna back up. Within another month I had
another broken rod. Each time the rod broke in the middle where the hole
is
drilled thru the center casting. After losing a single X-Hat rod the
resonant frequency jumped aprx. 200 khz making the antenna unusable on the
CW
portion of the band without a tuner. By the way, I did use the antenna
with
a tuner on the CW portion of the band and now my Cushcraft Balun has a
burn mark on it and it's warped!
I do not know what is causing my X-Hat Rods to break off. Perhaps the
rods center casting material was defective. But more likely it's the large
birds landing on my antennas including Ospreys and Owls... perhaps they are
flying into the X-Hats?
So I'd love to eliminate the X-Hat if possible.
73,
Dick- K9OM
In a message dated 2/8/2010 9:35:04 PM Eastern Standard Time,
ve5ra@sasktel.net writes:
X hat rods falling off - that is unusual. I've had my XM240 up for
years and never have the rods fallen off. I installed them as per CC.
So what is causing your rods to fall off or do you mean breaking off?
Doug
I'll run the race and I will never be the same again.
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of RLVZ@aol.com
Sent: February 8, 2010 4:44 PM
To: towertalk@contesting.com
Subject: [TowerTalk] XM-240 Shorty-Forty: X-Hat Modification
Hi Guys,
I've had problems with the X-Hat Rods falling off of my XM-240.
Therefore, I would like to eliminate the X-Hat by lengthening the
elements. I'm
wondering if anyone has done this successfully and how much length must
be
added to the elements?
Or if anyone has modeled the removal the XM-240 X-Hat by lengthening the
elements... please share what element lengths you came up with.
Thanks!
Dick- K9OM
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