Chet wrote:
> Hi Dick,
>
> I think you mentioned large birds on on yours xm-240. I have seen a couple
> of doves on mine but I guess I have been lucky. With doves sitting on it,
> it really does make the elements droop. Mine has been up 7 years now and no
> problem. I bought this used from K3OO who had it up for several years
> before that. This one took a lightning hit which Took out one of the coils
> and is one Of the reasons he sold it. I got a new coil from cushcraft about
> 10 days after I got the antenna home, I put it back up At 75 feet and its
> never blinked even through 5 hurricanes. I am about 7 miles off the water.
> Great antenna, I would definitely buy another one. Only once have
> I seen any ice at this qth.
Man, but am I Jealous! Nothing like coming out 3 or 4 times a year to
see the elements on your antennas loaded with ice and pointing at the
ground. That is a lot of flexing but bad as they look they've always
gone back up in place. OTOH my generator shed is directly under the
beams. The shed is one of those vinyl prefab units. I don't think it
even slows down a foot long piece of ice. Parts are easily replaceable
though.
73
Roger (K8RI)
> In truth this XM-240 has exceeded my wildest
> expectations.
>
> 73
>
> Chet N4FX
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of RLVZ@aol.com
> Sent: Tuesday, February 09, 2010 4:55 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] XM-240 Shorty-Forty: X-Hat Modification- Update
>
>
> Hi Guys,
>
> Thank You for the input regarding my XM-240 Shorty-Forty X-Hat rods
> breaking and falling off.
>
> For those who asked, the X-Hat Rods are 34-1/2" in length.
>
> I just went out and inspected the X-Hat assembly on my 1 year old XM-240.
> It is constructed as Joe said the original X-Hats were constructed: "The
> original X-hat elements were solid rod 3/16" in diameter with a 1.25" long
>
> by 3/8" OD sleeve crimped over the center of he rod before drilling for the
>
> #8-32 x 1.75" mounting bolt."
>
> Therefore, the "1.25" long by 3/8" sleeve crimped over the center of the
> rod" is a part of my X-Hat. I am very happy that most people have not had
> a
> problem with their X-Hat rods breaking and falling off! But if you think
> about it, the strength of the small 3/16" rod is almost entirely
> compromised when it was drilled thru to accomadate the #8-32 mounting bolt
> which is
> 1/8" in diameter. Therefore, about the only thing holding the rod together
>
> is the 1.25" long by 3/8" OD sleeve crimped over the center... which only
> provides 1/2" of support on each side of the hole! (and how strong is a
> crimped sleeve)
>
> I think we discovered why the "on the tower" life of my new XM-240 has not
> exceeded 1 month either time it was up. Either vibration from the wind
> and/or birds landing on the weakened 3/16" rods... cause them to break
> apart.
> By the way, when the 2 different 3/16" rods fell to the ground the 3/8" x
> 1.25" sleeve was no longer attached to any part of the 4 remaining rods
> pieces. I believe this indicates that the crimped sleeves probably failed.
>
> As an option to replacing the X-Hat with extended elements, perhaps I
> might consider using 3/8" aluminum rod with a 2nd sleeve over the center
> where
> drilled.
>
> 73,
> Dick- K9OM
>
>
>
>
>
>
>
>
>
> In a message dated 2/9/2010 4:12:52 PM Eastern Standard Time,
> na8w@hotmail.com writes:
>
> That's exactly what happened to mine.
>
> Darl NA8W
>
> --------------------------------------------------
> From: "Joe Subich, W4TV" <lists@subich.com>
> Sent: Tuesday, February 09, 2010 3:22 PM
> To: "'Tower and HF antenna construction topics.'"
> <towertalk@contesting.com>
> Subject: Re: [TowerTalk] XM-240 Shorty-Forty: X-Hat Modification
>
>
>>> I wonder why they fall off?
>>>
>> The original X-hat elements were solid rod 3/16" in diameter
>> with a 1.25" long by 3/8" OD sleeve crimped over the center
>> of he rod before drilling for the #8-32 x 1.75" mounting bolt.
>>
>> Newer antennas - or at least some production runs - appear to
>> lack the crimped sleeve as they fracture through the mounting
>> hole due to vibration. My guess is that the sleeve was
>> eliminated as a cost cutting measure <G>.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>>
>>
>>
>>
>>
>>> -----Original Message-----
>>> From: towertalk-bounces@contesting.com
>>> [mailto:towertalk-bounces@contesting.com] On Behalf Of Gregg Seidl
>>> Sent: Tuesday, February 09, 2010 1:57 PM
>>> To: Tower and HF antenna construction topics.
>>> Subject: Re: [TowerTalk] XM-240 Shorty-Forty: X-Hat Modification
>>>
>>>
>>> I wonder why they fall off? I've never heard of that. Mine
>>> have been up for
>>> 6 years now. Gregg K9KL
>>> ----- Original Message -----
>>> From: <RLVZ@aol.com>
>>> To: <towertalk@contesting.com>
>>> Sent: Monday, February 08, 2010 4:43 PM
>>> 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
>>>> _______________________________________________
>>>>
>>>>
>>> >
>>>
>>>> _______________________________________________
>>>> TowerTalk mailing list
>>>> TowerTalk@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>
>>> >
>>>
>>> _______________________________________________
>>>
>>>
>>>
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>> _______________________________________________
>>
>>
>>
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>>
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