On 11/8/2011 2:37 PM, Jeffrey Angus wrote:
On 11/8/2011 2:13 PM, John S wrote:
I think I am the confused one. Do I even need to know the transmission
line characteristics if I am going to short the load end and set the
vector voltmeter for a phase reference of 180 degrees?

I am following the HP app note AN-77 and they do not mention a
transmission line. They say to short the load end of the coupler. I need
to get my antenna away from the test setup, so I add the transmission
line.

The problem is that these measurements are designed to be made
as close to the instrument as possible. Adding a piece of transmission
line adds loss and phase shift to the measurement.

So unless you know how to work backwards from the measure you get to
what you're really measuring at the far end, you won't really have a
valid answer.

Jeff

Hi, Jeff -

Yeah, that's what I'm trying to learn by my questions.

Obviously, the antenna can't be sitting in front of the test equipment
so I'm trying to find a way to minimize proximity effects.

I should have used a different subject for the post, I think.

John