Jim Brown schrieb:
> On Sun, 31 May 2009 01:46:54 -0500, Phil Clements wrote:
>
>
>> The question is do they also need to be placed 15-30 feet away, or can they
>> be closer to the feed point?
>>
>
> As the designer of the coax chokes using clamp-ons or toroids, I'll step up
> to
> respond. They are a real "brute force" design, adding a VERY high impedance
> in
> series with the common mode circuit. As a result, they do not require the
> additional ground rods in the DXE design. Ideally, the choke should be very
> close to where the coax terminates to the matching transformer.
>
> Other chokes have significantly lower impedance than my designs, so they need
> be be used with a "network" -- in this case, the path to ground via the rods
> to
> provide sufficient isolation.
>
> Note that there's nothing "magic" in my designs -- everything is documented
> in
> the RFI tutorial that's on my website, and in the accompanying power point on
> coax chokes.
>
> 73,
>
> Jim K9YC
>
>
>
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>
>
Some very good experiments and reports with coax-chokes and 1: X
Transformers can be read here (sri, german only):
http://www.wolfgang-wippermann.de/
Have fun
Lup, DJ7SW alias DL0KF
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