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I'm real time on my H4, so hope this maps to yours.

QUOTE (Dean, W8ZF): This just confuses me again. "Remove the calibration
and save that to the default slot (0 slot) when using NanoVNA Saver."

Remove *which* calibration? And save *what* to slot 0? Are you talking
about the H4 device? Do you mean from the calibrate menu, choose "Reset"
and then "Save" to memory 0?
What values does this put into memory 0? And since nanovna-saver depends
on the calibration of the H4 device, what is that calibration now (after
reset and store 0)?

"When you calibrate the Nano (on device calibration) in the range as the
documentation suggests 0-900MHz with 401 points..."

Where is there an option on the H4 device to select the number of points
used for calibration? I haven't seen that as a menu option.

Calibrating on the native NANOVNA, there is no choice for number of
points. I believe it will default to the maximum number of points which is
401 (??).

Always remember to "RESET" before a new calibration.
***

If the calibration of nanovna-saver gives different results, depending on
the state of the H4's calibration, I don't know what to believe.

It depends on how different the results are. Remember, the FW interpolates
between measured and stored cal values. Saver can be configured with 1001
points so the cal. sampling is much finer than a cal. on the native NANOVNA
(without SAVER).
***

Forgive me, I still don't understand how this works together. I don't see
why nanovna-saver can't just read raw results from the H4, and then use
those for a calibration (which would make it independent of the H4's
calibration). There have been some mentions about different numbers of
points, about reporting invalid values, etc.

Again, using SAVER, there is the option to use considerably more points for
calibratioin: Native is 401 points, SAVER allows up to 1001 points. So
extrapolation between measured points using the two calibrations will be
coarser with the native VNA cal than with the SAVER cal.

If you simply were able to upload the native cal (H4 alone) to SAVER, you
would not take advantage of a number of additional measurements and
presentations. SAVER is considerably more powerful than the FW within the
native NANOVNA.
*


Does anyone KNOW, not guess, what the proper procedure to calibrate this
system using nanovna-saver is? Nanovna-saver is what it is, I'm not
bashing it or trying to change it -- I'm just trying to understand the
limitations and requirements to get good results out of the software. The
ability to store calibrations, write s-parameter files, and plot using
different formats is invaluable to me. I *really* want to use it for these
features, but not if I can't be sure of the measurement.

Once you have "woke up" your NANOVNA by a native calibration, connect and
run SAVER. Treat SAVER as a totally independent set of FW/SW from that
within the NANOVNA. SAVER has all the options to connect, reset, do a
complete cal potentially with more points than the native NANOVNA can
support. Again, SAVER offers much more capability the the FW embedded
within the native NANOVNA.
***

General Comment: Remember we are not expecting metrology lab comparisons
between the native NANOVNA and the SAVER results/measurements. Differences
with carefully and faithfully duplicated setups, disagreements in the first
significant figure, or maybe in the second, should be of little concern.

For example, if you measure a single 50-ohm resistos with three different
DMMs, you will get three different results. Here you go using a stock
50-Ω, 3%, 1-watt resistor:
[image: image.png]


INSTRUMENT MEASURED VALUE (Ω)

HP 3478A 49.994

Cen-Tek P37772 50.1xx

Sperry DM-6400 49.8xx

HP 4261A LCR Mtr 50.8xx

Well, which one would you pick? Is it a 50-Ω resistor? None of the
measurements indicate it's 50-Ω. Is it within the 3% specification of ±1.5
% or ± 0.75 ohms? Yes, by three of the four measured values made on four
different instruments.

Dave - W?LEV

On Mon, Apr 28, 2025 at 8:25?PM Dean W8ZF via groups.io <dwfred=
[email protected]> wrote:

Dragan,
This just confuses me again.

"Remove the calibration and save that to the default slot (0 slot) when
using NanoVNA Saver."

Remove *which* calibration? And save *what* to slot 0? Are you talking
about the H4 device? Do you mean from the calibrate menu, choose "Reset"
and then "Save" to memory 0?
What values does this put into memory 0? And since nanovna-saver depends
on the calibration of the H4 device, what is that calibration now (after
reset and store 0)?

"When you calibrate the Nano (on device calibration) in the range as the
documentation suggests 0-900MHz with 401 points..."

Where is there an option on the H4 device to select the number of points
used for calibration? I haven't seen that as a menu option.

If the calibration of nanovna-saver gives different results, depending on
the state of the H4's calibration, I don't know what to believe.
Forgive me, I still don't understand how this works together. I don't see
why nanovna-saver can't just read raw results from the H4, and then use
those for a calibration (which would make it independent of the H4's
calibration). There have been some mentions about different numbers of
points, about reporting invalid values, etc.

Does anyone KNOW, not guess, what the proper procedure to calibrate this
system using nanovna-saver is? Nanovna-saver is what it is, I'm not
bashing it or trying to change it -- I'm just trying to understand the
limitations and requirements to get good results out of the software. The
ability to store calibrations, write s-parameter files, and plot using
different formats is invaluable to me. I *really* want to use it for these
features, but not if I can't be sure of the measurement.

73,
Dean W8ZF

--

*Dave - W?LEV*


--
Dave - W?LEV