> Ok... Then please list the copper coated steel coax cables.
>
> 73
> Jim W7RY
>
>
> --------------------------------------------------
> From: "Perry" <k4pwo@comcast.net>
> Sent: Friday, July 22, 2011 4:46 PM
> To: "Jim W7RY" <w7ry@inbox.com>
> Subject: Re: [TowerTalk] DX Engineering DXE400MAX Cable?
>
>> Read it again... He says to stay away from Cu on steel, not Cu on Al.
>>
>> 73 de Perry - K4PWO
>>
>> Sent on the Sprint® Now Network from my BlackBerry®
>>
>> -----Original Message-----
>> From: "Jim W7RY" <w7ry@inbox.com>
>> Sender: towertalk-bounces@contesting.com
>> Date: Fri, 22 Jul 2011 16:30:39
>> To: <jim@audiosystemsgroup.com>; <towertalk@contesting.com>
>> Reply-To: Jim W7RY <w7ry@inbox.com>
>> Subject: Re: [TowerTalk] DX Engineering DXE400MAX Cable?
>>
>> What does this statement really mean Jim? You say to stay away from
>> copper
>> coated aluminum, but then say there is no increase in loss at 1MHz.
>>
>> Please clarify.
>>
>> 73
>> Jim W7RY
>>
>>
>> Q: What about copper coated steel and copper coated aluminum?
>> A: For frequencies below 10 MHz, avoid copper-coated steel. At higher
>> frequencies, skin
>> effect takes over, and all the current is in the thin coating, but at
>> lower
>> frequencies, the
>> steel increases the resistance (and the loss). Measurements of LMR400,
>> which
>> has a
>> copper coated aluminum center conductor, show no increased loss due to
>> the
>> higher
>> resistance of the aluminum, even as low as 1 MHz.
>>
>>
>>
>>
>> --------------------------------------------------
>> From: "Jim Brown" <jim@audiosystemsgroup.com>
>> Sent: Friday, July 22, 2011 11:54 AM
>> To: <towertalk@contesting.com>
>> Subject: Re: [TowerTalk] DX Engineering DXE400MAX Cable?
>>
>>> On 7/22/2011 5:28 AM, Mark Robinson wrote:
>>>> I would call DX Engineering and ask them who makes their DXE cable for
>>>> them
>>>> and how it compares to the Davis equivalent.
>>>
>>> YES. Also, there is NO good reason for a foil shield at HF, and several
>>> authorities have noted long term aging issues with contact between the
>>> braid and foil. W2VJN noted this in the latest edition of his excellent
>>> book on Managing Interstation Interference with respect to the stability
>>> of stubs made with LMR400.
>>>
>>> I suggest that you study my tutorial on Coax and Stubs.
>>>
>>> http://audiosystemsgroup.com/Coax-Stubs.pdf
>>>
>>> IMO, the Davis stuff hits the sweet spot for HF operation, based on
>>> performance specs and cost.
>>>
>>> 73, Jim K9YC
>>> _______________________________________________
>>>
>>>
>>>
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>>>
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>> _______________________________________________
>>
>>
>>
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