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DiSlord,

This morning I started using the NanoVNA-H4 loaded with your firmware number 3 as yesterday. .

1) Started NanoVNA-Saver.

2) Did a reset in "calibration".

3) Did a full calibration (2 port).

After calibration (doing the "through"calibration) NanoVNA showed as picture number 1 (not pressed "Apply")

After pressing "Apply" NanoVNA showed as picture Number 2

After running again NanoVNA shows same as picture 2

Normally after calibration NanoVNA-Saver shows as picture Number 1 just after pressuring "Apply" if I remember well....Looks very much like saving the callibration is wrong !!!.... Did you check in NanoVNA-Saver ?

Jos

Op 27-4-2020 om 23:44 schreef DiSlord:

DiSlord,

Don't understand either, I always do reset before calibration. Will flash the previous working firmware again today to check if it still works.

Jos

Op 27-4-2020 om 23:44 schreef DiSlord:

On Mon, Apr 27, 2020 at 02:41 AM, Roger Need wrote:

Here is a second report on the effect of calibrating the NanoVNA on SWR and
Return Loss measurements. This time a 20M dipole was used as the antenna. It
was surprising to me to see how good the measurements were when using the
default 50 kHz. to 900 MHz. calibration and setting the Stimulus range to 13
to 15 MHz. Interpolation works well under certain conditions.

I have made a *table* to better see what is the result of the measurements from the PDF file.

Calibration MHz Scan MHz SWR RL dB
0.05 - 900 1 - 30 1.20 20.56
1 - 30 1 - 30 1.19 21.12
0.05 - 900 13 - 15 1.12 24.42 good result for practical use
1 - 30 13 - 15 1.12 24.74
13 - 15 13 - 15 1.12 24.67
14 - 14.35 14 - 14.35 1.12 24.74

*Result* : A full span calibration is sufficient for practical use.
How smaller the scan width, the better the SWR / Return Loss.

73, Rudi DL5FA

On Mon, Apr 27, 2020 at 02:13 AM, Roger Need wrote:

I did some measurements today on a vertical whip antenna tuned for the top end
of the 2 m amateur band.

I have made a table to better see what is the result of the measurements from the PDF file.
For my understanding here the *precision of the frequency* is important.

Calibration MHz Scan MHz Step KHz SWR RL dB Lag KHz
0.05 - 900 0.05 - 900 9000 1.25 19.04 153.041-147.76= 5281
0.05 - 900 140 - 155 150 1.06 29.6 148.400-147.76= 800
140 - 155 140 - 155 150 1.07 29.13 147.600-147.76= 200
140 - 155 146 - 150 40 1.06 29.61 147.800-147.76= 40
146 - 150 146 - 150 40 1.06 30.34 0

*Result* : The frequency lag of maximum RL can not be (much) better, than the measuring step size.
So, watch the *Step Size* = scan width / 100.

73, Rudi DL5FA

On Mon, Apr 27, 2020 at 01:51 PM, <aleks07111971@...> wrote:

What is the approximate cost of the device?

Not sure yet. Target is comparable to one of the nanoVNA family

--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

If you really still need testers, I might be able to contribute.
For my day job, I use an HP3585A for phase noise measurements.? Impressive dynamic range on that tank.
Also a Rigol for field measurements of RFI in the HF band at the 'other' US radio quiet zone you nave never heard about.? Near Boulder Colorado.
I'm doing radio astronomy and HF and LVHF and have several NIST calibrated diode noise sources.

If I can help.
Terry
W0ASP

This very timely as I have spent the last couple of days looking at Spectrum analyzers to replace my old CTE one.
--
Terry VK5TM
( )

Dave is correct. The VSWR doesn't vary along the transmission line except
for a small variation due to loss of the transmission line. If you do see
the VSWR vary, that indicates imbalance on the transmission line. For coax,
this means RF is on the outside of the coax shield.
73, Carey, WB4HXE


On Mon, Apr 27, 2020 at 4:38 AM Dr. David Kirkby, Kirkby Microwave Ltd <
drkirkby@...> wrote:

On Fri, 24 Apr 2020 at 15:51, <whdpc113@...> wrote:

If you have a bad mismatch, the reactive part of the impedance will vary

along the length of the feed line. What your rig sees at the end of the
feedline, and what the MFJ sees with a jumper and your rig behind it may
differ. Does the SWR reading on the rig change with and without the MFJ
inline? I have found VHF and UHF antenna SWR very sensitive to small
changes in length/tuning.

With a VSWR > 1, *both* the real and imaginary (reactive) part of the
impedance vary as one moves along a transmission line. It is not just the
imaginary component as you say. If that transmission lines was lossless,
the VSWR would remain a *constant*, not vary as you say. The impedance
varies along the transmission line, but the VSWR remains constant.

What any piece of test equipment shows depends on its quality.

Dave, G8WRB.
--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom

--
Carey Fisher
careyfisher@...

On Mon, Apr 27, 2020 at 03:16 PM, Eric Furness wrote:

I Upgraded to 0.1.1 All worked ok. How do you get to the TDR function?
=====================================================
DISPLAY->TRANSFORM

From there you have to choose one of the step functions (see various user manuals). Works the same as on on NanoVNA.

- Herb

On 4/27/2020 5:38 AM, June wrote:

v0.1.4 2020-03-26 : This update requires recalibration of the device
1) Supports 0dBm output (fundamental frequency, for HW V3.1 & HW V2.3 only, for HW V2.2 still -13dBm output);
2) No new features were added compared to firmware v0.1.1.
How to know my NanoVNA-F HW version?: /g/nanovna-f/wiki/How-to-know-my-NanoVNA-F-HW-version
v0.1.0&v0.1.1 2020-02-03 : This update requires recalibration of the device
1) Add TDR feature;
2) Add marker tracking feature & dynamic update of frequency and other information when the mark moves;
3) Add ordinate display
4) Support to 10kHz frequency
5) Some font, color, and layout optimizations
6) Suggestions from groups.io/nanovna-f & facebook group members and much more, thank you for your feedback
(1) a beep to the end of each standard measurement in calibration
(2) callsign.txt expanded to 44 chars, not limited to call sign display, can display your phone and email address, etc.
7) The startup information is not displayed for a long time at present, you can call it up in the menu. Just into the menu: CONFIG -> ABOUT
v0.0.5 2019-12-30 : This update requires recalibration of the device
1) Support measurable frequency to 1.5 GHz, default setting 1 GHz, accurate measurement up to 1.35GHz;
2) Fix: unexpected 0.3dB offset of s21 in thru;
3) Fix: mark all off bug;
4) Fix: clutter display when standing wave ratio is infinite;
5) Add version & info command;
6) Add REAL IMAG R X trace format.
v0.0.4 2019-10-30 : This update does not require recalibration of the device
1) Can display call sign;
2) fix BUG: CW=100MHz do not output
3) Optimize Chinese translation
4) How to display your call sign: /g/nanovna-f/wiki/How-to-add-call-sign-display
v0.0.3 2019-10-07 : This update requires recalibration of the device
1) support NanoVNA's PC software;
2) Add a boot tone;
3) Optimize band (<100MHz) S11 measurement results
v0.0.2 2019-08-29 : First Release

I Upgraded to 0.1.1 All worked ok. How do you get to the TDR function?

Eric WA3UYI

--
This email has been checked for viruses by Avast antivirus software.

Only if have problem, if you get correct result, not need do it.

Recalibrate need if threshold value change (possible not correct calibration point near harmonic change)

On Mon, Apr 27, 2020 at 01:18 PM, DiSlord wrote:

Please not use old calibration, recalibrate after update
=========================================
DiSlord,
I haven't had any issues with 0.8.4.3 or 0.8.4.4 but I do have a question. After updating to each version my calibrations in each slot were still good, when re-checked using my SOLT standards, so I didn't re-calibrate. Is it absolutely necessary to re-calibrate after updating or only if you are experiencing issues?

- Herb

DiSlord,

Flashed number 3, calibrated NanoVNA-Saver, measured S21 and 49.85 standard see the pictures.

Call it a day for now.

Jos

Op 27-4-2020 om 22:18 schreef DiSlord:

i don`t understand
1 variant is last firmware
2 variant - is 0.8.4.3 (Only 8kHz IF change)
3 variant - is old 0.8.4.4 (2x external freq)

You not fogot reset self NanoVNA calibration before calibrate in NanoVNA Saver?

Try restore last worked firmware

DiSlord,

Flashed number 2,? threshold set to 300MHz,? recalibrated NanoVNA-Saver,? S21 at 0 now,? R+jX? R still not shown, S11 49.85 Ohms standard? way off , Marker 1 an 3 not shown. See pictures.

Jos

Op 27-4-2020 om 22:15 schreef DiSlord:

DiS;lord,

Flashed number 1, recalibrated in NanoVNA-Saver, still no good, see picture

Jos

Op 27-4-2020 om 22:15 schreef DiSlord:

What is the approximate cost of the device?

Please not use old calibration, recalibrate after update

Check this 3 variants (all of them work good on my H4, try set threshold to 300MHz)

Need recalibrate

In version v0.8.4.4, the level of CH1 rises after 300 MHz.