On Mon, Nov 11, 2019 at 07:24 PM, WB2UAQ wrote:
All network analyzers that I have worked on (repaired, calibrated and use
nearly every work day) since 1977 (8409, 8505, 8753, 8510.......) have the
test ports connected to and thru the same front panel (built in or on the
S-parameter test set). I see absolutely no reason to isolate them on the nano.
I have not used the isolation part of the cal yet but isn't that the reason
for doing isolation?
Thank you Pete and Dana for your helpful replies.
I connected the two supplied SMA cables to the nvna and calibrated from 10kHz to 1500MHz.
With both ends terminated in 50 Ohms the nvna cannot measure any difference in isolation with the grounds of the load ends floating or connected. In the attached picture the isolated plot is green and the connected plot is red. Both are averaged over 100 scans. Worst case isolation is 45dB @ 1.5GHz limited by the nvna itself.
See also post #6867.
