Sent from my iPhone
> On Jun 23, 2016, at 7:10 PM, Edward McCann <edwmccann@yahoo.com> wrote:
>
>
>
> Sent from my iPhone
>
>> On Jun 23, 2016, at 6:27 AM, Edw McCann <edwmccann@aol.com> wrote:
>>
>> Any suggestions how to apply this concept to ladder line/open feed?
>>
>> Ed McCann
>> AG6CX
>>
>> Sent from my iPhone
>>
>>> On Jun 23, 2016, at 12:48 AM, Ian White <gm3sek@ifwtech.co.uk> wrote:
>>>
>>> VE7RF wrote:
>>>
>>>> ## Ian mentions the current. If that’s the case, why not just
>>>> measure the current with a clamp on ammeter.... at say
>>>> several random places on the coax feedline ?
>>>
>>> That is exactly what I try to do - see my website: "Clamp-on RF Current
>>> Meter - *the* most useful tool for RF interference troubleshooting."
>>> http://www.ifwtech.co.uk/g3sek/clamp-on/clamp-on.htm
>>>
>>> A perfectly functional instrument can be thrown together in half-an-hour.
>>> The passive diode detector will typically read from about 25mA up to 1A. It
>>> is also possible to build a much more sensitive log-scale instrument based
>>> on an AD8307 detector chip (or similar) which will read down to 1mA, but
>>> with reduced resolution.
>>>
>>>> Then we have yet another issue to deal with, and thats
>>>> what if the coax braid is bonded to the top of the tower ?
>>>> If a lousy CM choke balun is used at the ant feedpoint,
>>>> and braid also bonded to top of tower, we can then have
>>>> a case where CM current is now flowing down the tower.
>>>
>>> Well jes' don't do that! Don't use a lousy CM choke at the feedpoint, use a
>>> good one; and if in any doubt, use another CM choke (which doesn't have to
>>> be so good) just above the point where the braid is bonded to the tower.
>>>
>>> Or best of all, measure the CM current both before and after.
>>>
>>>
>>> 73 from Ian GM3SEK
>>>
>>>
>>> _______________________________________________
>>>
>>>
>>>
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