For sure - I had terrible line noise a few years ago that was traced to
a lightning arrestor on top of a nearby pole. Seems a woodpecker had
undermined one of the two lag bolts - it had come loose and was just
sitting in the hole in the pole and the arrestor bracket. The lineman
who fixed it (by removing the loose bolt) told me that the field
gradient near the 7500 volt line was enough to cause sparking between
the bracket and the loose bolt,l and that his company now used a 1-bolt
bracket to avoid this problem - I guess they would rather have the
arrestor fall of altogether, rather than deal with RFI complaints.
73, Pete N4ZR
The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at
reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000
On 7/23/2010 7:02 PM, K1TTT wrote:
> No, metal on metal rubbing by itself doesn't cause interference. But if
> there is a voltage difference between the parts that are rubbing THAT can
> cause interference.
>
>
> David Robbins K1TTT
> e-mail: mailto:k1ttt@arrl.net
> web: http://www.k1ttt.net
> AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
>
>
>
>> -----Original Message-----
>> From: Michael Fox - N6MEF [mailto:n6mef@mefox.org]
>> Sent: Friday, July 23, 2010 22:03
>> To: towertalk@contesting.com
>> Subject: [TowerTalk] metal-on-metal interference
>>
>> I've heard that metal-on-metal rubbing contact causes RFI. But doing some
>> Google searches, I can't find a source of information.
>>
>>
>>
>> Can someone tell me:
>>
>> 1) Is this true?
>>
>> 2) If so, is there a source for information?
>>
>> 3) Specifically, is there a general frequency range for the interference?
>>
>>
>>
>> Thanks much,
>>
>> Michael
>>
>> N6MEF
>>
>>
>>
>> _______________________________________________
>>
>>
>>
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>>
>
> _______________________________________________
>
>
>
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>
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