View Single Post
  #33   Report Post  
Old January 3rd 06, 08:36 AM posted to rec.radio.amateur.antenna
Owen Duffy
 
Posts: n/a
Default using an HP 8405A to measure SWR ?

On Mon, 02 Jan 2006 23:06:43 -0800, Richard Clark
wrote:

On Tue, 03 Jan 2006 06:42:53 GMT, Owen Duffy wrote:

(The phase angle and reflected ware very touchy. It was almost impossible to
adjust by changing frequency. It was easier to 'adjust' it by sitting very still
and moving my arm.)


...Does that
explain some of the phase sensitivity?


Hi Owen,

Being very touchy, especially to the specifics of sitting very still,
sounds like classic common mode problems.


Yes it does Richard. I saw Roy's response regarding isolation of the
feedline, and it is a valid comment. My comment was towards the
reported frequency sensitivity... until the effect of the propagation
delay is removed from the results, the underlying impedance is
obsured.

Owen
--