[Amps] Input SWR revisited

[Paul Christensen]

Roger, that's right - I forgot that the VNA was being used and not a 
directional line coupler.

The results are not surprising.   However, it would be interesting to 
observe SWR at the VNA with random changes in line length between the VNA 
and the tuner when he used: (a) the 4 ft. section between the tuner and 
75-ohm resistive load; and (b) a 19-inch line section between the VNA and 
tuner.   If I have his facts straight, that showed an SWR value of 1.8:1.

If Gary was trying to use the tuner to emulate an amplifier input network, 
then what we want to see is measured SWR sensitivity to change as a function 
of line length between the VNA and tuner when a non 1:1 SWR is present 
between the tuner and load.

Paul, W9AC

-----Original Message----- 
From: Roger D Johnson
Sent: Tuesday, January 13, 2015 9:21 AM
To: Paul Christensen
Subject: Re: [Amps] Input SWR revisited

The VNA does not measure the VSWR on the line. It measures VSWR at the
input to the VNA unless you do a cal at the load end of the line to remove 
it's
effect.

73, Roger