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Thanks, I've updated mine and it works great as well!

M

Thanks to all!

Sorry, should be Michael, not Mario.

Mario, - calibration does just thet - it calibrates out (ideally, of course) all the variables and takes into account delayes, parasitic LC, etc so that at the reference plane, you have an 'ideal' match with with to test with.
Also, please only enter your replies only once and delete any duplicates as they clog up the forum with 'noise' so to speak.
Thanks
Larry

Larry,

If you do calibration with the adapter installed and the reference plane is at the adapter would you still have to adjust for the electrical delay?

Mike N2MS

On 9/14/21 4:58 AM, Chris Pohlad-Thomas wrote:

I assume when everyone is using adapters they adjust the electrical delay to account for these?

or you calibrate with standards that attach to the adapter, so the adapter is "inside" the calibration plane.

If the delay of the adapter is significant, then yes. For most of my 900 MHz work it is. For 1 MHz, it isn't.


Op 14-9-2021 om 13:58 schreef Chris Pohlad-Thomas:

You can do that (I have) but the best way is to calibrate the unit with the adapters installed to move the reference plane to account for them.

I assume when everyone is using adapters they adjust the electrical delay to account for these?

I took a closer look and there are more of these interferences. They are very narrowband. If the measuring point falls farther than the filter band, they are not there. It has nothing to do with the DVB-T TV or the received signal from the neighborhood. The device is disconnected from everything. I checked with an RTL-SDR tuner and I don't see a connection between these signals and what is on the air.
In CW mode, you can see sinusoidal interference on a slight off frequency of these bars. Sample screenshots are attached.
List of problematic frequencies I was able to find:
463.105 - 1dB
463.121 - 1dB
471.222 - 5dB !!!
487.458 - 5dB !!!
498.331 - 1dB
520.026 - 0.3dB
536.230 - 0.5dB
552,472 - 0.5dB
568,753 - 2dB
585,018 - 2dB

Hello Phil!

Have You read a File Section?
/g/nanovna-users/files/Absolute%20Beginner%20Guide%20to%20The%20NanoVNA

Your device NanoVNA H4 (not H3) and Firmware Version 1.0.45 from Hugen.

Here is newest Firmware /g/nanovna-users/files/Dislord%27s%20Nanovna%20-H%20Firmware/NanoVNA%20v1.0.69%20fw%20pack.zip
please unzip and take Yout version for H4

Here is Structure Map for NanoVNA H4 from Hugen for FW Version 1.0.69
/g/nanovna-users/files/NanoVNA%20Menu%20Structure%20Map-v1_0_69.pdf
Best regards
Vladimir

Confirming that "-H" variant works on the "Classic" NanoVNA. Just updated it after reading this thread.
Compared with crystal measurements done on SAA-v2 with OjisanKobou FW. There is a little bit of difference, around 100Hz for the series resonance. Most likely because I didn't calibrate the TCXO frequency on either unit. Lm and Cf are very close.

73, Mike AF7KR

Colours can only be set through the console when connected to a PC, and the saved.?
Please read up on searching the forum - it's the first link at the top of the wiki.?
A search of console and color finds this thread....
/g/nanovna-users/topic/84120122#23255
It has the info you need.?


I have just got an H3 Nano VNA its running ver 1.0.45 (Jan 2021 by @Edy555) of the firmware and when I received I was sure the Traces were all separate Colors (But I may have been mistaken) now however the traces are all the same color. Watching several of the how-to YouTube video I noticed those unit displayed different traces in different colors and have been trying to work out how to get my NanoVNA to display traces in different colors. So it raises a few questions:
Is what I'm trying do even possible?
If yes, is this a feature of later firmware than what I have?


I have search through the Menu and not found anyway to set colors Also trolled through the messages here and likewise I have found and description of how to set the colors on the device. I have Both VNA Saver and VNASharp and while I can see how to set colors in the VNA saver app this does not extend to outputting those colors to the device itself.

Any help or guidance would be much appreciated.

Phil

I have just got an H3 Nano VNA its running ver 1.0.45 (Jan 2021 by @Edy555) of the firmware and when I received I was sure the Traces were all separate Colors (But I may have been mistaken) now however the traces are all the same color. Watching several of the how-to YouTube video I noticed those unit displayed different traces in different colors and have been trying to work out how to get my NanoVNA to display traces in different colors. So it raises a few questions:
Is what I'm trying do even possible?
If yes, is this a feature of later firmware than what I have?


I have search through the Menu and not found anyway to set colors Also trolled through the messages here and likewise I have found and description of how to set the colors on the device. I have Both VNA Saver and VNASharp and while I can see how to set colors in the VNA saver app this does not extend to outputting those colors to the device itself.

Any help or guidance would be much appreciated.

Phil

DELAY has to be understood here as "Group Delay". It highlights the transit time of a signal through a DUT (Device Under Test) versus frequency. It is usually currently related to transmission measurement (s21).

Its calculation is the mathematical derivative of the phase with respect to frequency. If there is PHASE distortion, i.e. a breakout on its monotonous variation according to frequency, the group delay remains no more at a constant value.

Group Delay = -(1/360)*(phi2-phi1)/(f2-f1)

For the NanoVNA, (f2-f1) is the elementary frequency step (Hz) between two measurement points, which depends of FSTART, FSTOP and choosen number of measurements points (101 ... 401). It means that (phi2-phi1) is the phase value difference (Degrees), between two neighboring measurements points.

Group Delay is a relevant parameter, when for example you consider a non-sinusoidal signal passing through a filter. If Group Delay is not constant, the shape of the signal will be altered at the output of the device, due to a possible time shift on its harmonic components.

A last word about Group Delay when related to reflection measurement (s11). It's less intuitive, but we can consider this example with a DUT which is an opened coaxial cable (length 2 meters), one of my favorite educative DUT ! Here the Group Delay (around 18,2 ns, see snapshot) highlights the total transit time at Port 0 level, i.e. a round trip of the signal through the coaxial cable. From it you can calculate the electrical length of the coaxial cable, and if you know the velocity factor, its physical length.

Round trip : 300.000.000 (m/s) * 18,2 E-09 = 5,46 m
Electrical length : 5,46 / 2 = 2,73 m
Physical length : 2,73 * 0,73 = 1,99 m 0,73 is the velocity factor value for RG58A/U cable type

As advanced firmware for NanoVNA now includes automatic calculation for coaxial length (thanks to DiSlord) based on Smith chart, the previous method is not necessary the most accurate or relevant. It is just for an explanation of Group Delay in s11 measurement context.

Jean-Roger / F6EGK

Mario,
The 'classic' includes all NanoVNA models from the very 1st model (and clone) up to and including the H (but not the H4).
I'm running the latest 1.0.69 on my classic with no issues.

Which variant (if any) works with the Classic (Pre-H) VNA. This never seems completely clear from the descriptions - I think because there's no consistent way to describe the original unit.

thanks,

M

The wiki page Home has been updated by Larry Rothman <nlroth@...>.

Reason: Added document link to post on measured parameter definitions

Compare Revisions

Joe,
Many of the questions you keep asking are in both the forum wiki and the various user guides in the forum files section.?
Please read the user guides.? start with the Absolute Beginners Guide.?


On Sun., 12 Sep. 2021 at 11:48 a.m., Joe WB9SBD<nss@...> wrote: Ok,
Good,

Now if I was to save to Save-1, how does one use save 1 in the future?

Joe WB9SBD

I have gotten some great input about this, but it remains a problem that such outputs as “real” and “imaginary” come with no documentation as to what they are. I have written a 1 pager that some moderator may want to review, edit, and add to the wiki. I don’t even know how to attach things to this group in a way that they carry through, so I will cut and paste it:

NanoVNA Output Variables



LOGMAG – For S11 measurements this is the Return Loss and is measured in dB. For passive networks it will always be negative. For S21 measurements this is the INSERTION LOSS in dB.

SWR – The Standing Wave Ratio, often also called Voltage Standing Wave Ratio (VSWR), is often used for measuring antennas. For S11 measurements an SWR of 1 is a perfect match (zero reflected power). The figure is normally quoted as a ratio (e.g. 2:1). An antenna SWR of 3:1 would normally be considered good, while lower than 2:1 would be excellent. Use of SWR for S21 measurements may be meaningless.

LINEAR – Same as LOGMAG, but expressed as a ratio. For S11; 1 would be 100% power reflected, 0 would be 0% power reflected.

PHASE – The relative phase difference or delay between the signal source voltage and received signal voltage.

SMITH – This is a chart of resistance and reactance. The (real) resistance is shown on the horizontal center line, with 0 ohms (a short circuit) at the 9 o’clock position and infinite ohms (an open circuit) at the 3 o’clock position. The center point indicates whatever normalized resistance is being used, but for the nanoVNA it is always 50 ohms. Any point above the horizontal center line indicates positive (i.e. inductive) reactance and any point below indicates negative or capacitive reactance. This output reports the capacitance (C) or inductance (L) at the marker position. Note that a transmission Smith chart, on CH1, may be meaningless.

POLAR – Same trace as the SMITH chart, but provides the voltage reflection coefficient as a complex number, as shown on marker readings. On this chart, the 9 o’clock position represents -1+j0, the 3 o’clock position is 1+j0, and the 12 and 6 o’clock positions are 0+j1 and 0-j1 respectively.

DELAY – ???

REAL – This is simply the real part of the reflection coefficient gamma (i.e. the number on the Polar chart).

IMAGINARY – This is the imaginary part of the reflection coeff. gamma (i.e. the number on the Polar chart).

RESISTANCE – This is the resistance encountered in the DUT, as shown on the Smith chart.

REACTANCE – This is the reactance of the DUT, as shown on the Smith chart.