I should have also mentioned in detail how you measure things. Choose
"Display," then "Format S11 (Refl)." Looking down the list you will see
"Resistance" and "Reactance." Choose which you want to measure. You can do
further measurements by choosing "More" twice. In the choice of options,
you will see "Parallel R,' "Parallel X", "Parallel C" and "Parallel L."
(These are the best choices for measuring a single capacitor or inductor
connected as I described below. Note, the numbers of the reactance,
resistance and inductance vary with frequency and you would need to choose
an exact frequency by rocking the rocker arm back and forth to display the
values at one frequency.
Zack W9SZ
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On Fri, Jun 23, 2023 at 12:28?PM Zack Widup <w9sz.zack@...> wrote:
I have some SMA right-angle connectors. The center pin of coax is supposed
to solder to the inner pin connection in the connector, and the shield is
crimped with a ferrule to the connector. But what I did was solder a wire
about 3 inches long to the inner pin connection and another wire to the
outer (ground) area of the SMA connector. This minimizes the capacitance
between the wires. (This is significant!) I measure 3.5 pF with my leads
and connector.
Make sure your NanoVNA is calibrated for the frequency range you want to
measure. Put the SMA connector on the s11 (top) port of the NanoVNA. Solder
the wires to the two leads of your inductor. You can then measure its
reactance, resistance and inductance with the appropriate measurement
settings of the NanoVNA.
I've done this with dozens, maybe hundreds of inductors,
Zack W9SZ
On Fri, Jun 23, 2023 at 11:42?AM Steve Johnson <cascadianroot@...>
wrote:
Garry says:
¡°¡ Then attach your inductor. ¡¡±
The devil is in the details with such a simple-sounding statement. Attach
it how? There are 2 ports on the NanoVNA, each with a center conductor and
an outside conductor (called, shield, ground, body, etc.) The inductor
(DUT) has a single conductor with 2 ends. So, exactly how do you connect
those 2 ends to the NanoVNA ports? Considering there is also an option of
leaving certain ports, wire ends, or conductors (center/shield)
disconnected, there are more than 10 possible options.
Then, once some sort of connection is made between inductor and VNA,
which measurement option (menu choice) do you select on the NanoVNA? S11,
S21, shunt, thru, etc. This decision adds more complexity.
For those experienced/ trained in using VNA¡¯s and deciding such things
for multiple different types of DUT¡¯s, these may be such basic questions as
to be assumed inherently obvious. But they are not inherently obvious to
the new VNA users attracted to forums such as these.
