[TenTec] OT: SWR & Coax

[Dr. Gerald N. Johnson]

On Mon, 2008-07-07 at 15:39 +0800, Marinus Loewensteijn wrote:
> 
> When Coax is terminated at the transmitter end and the far end with an impedance that is equal to its defined impedance we will have a SWR of 1:1.
> 
> Only when the currents on inner conductor and on shield are equal and the current / voltage nodes coincide at the same locations then they'll cancel radiation.
> 
> If we have anything else that creates a SWR that is not 1:1 then waves will be reflected from the ends.  Hence no longer will the current and voltage nodes be coinciding.

So long as the shield is intact, it matters not whether the nodes match,
there is current only on the inside of the shield and that can't
radiate.
>  
> 
> When nodes are no longer coinciding then we will have radiation.
> 
> What is wrong about this, what am I missing here?

You are forgetting that the coax is shielded and that limits radiation.

> 
> Thanks, 73, marinus, ZL2ML

73, Jerry, K0CQ