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So i have in front of me a brand new in package/container: a brand new -f v2
All metal housing, protective plastic on screen.
Upon start. Turn on. Screen flashes white then goes dark.
Very faint lines and bars visible.
This is a brand new unit.
I am disinclined to take apart and mess with internals.

Should i return? Warranty?
How good is the company/manufacturer customer service?

I have NanoVNA-H version 3.6.1_SM_ST. I had 1.2.27 (20.02.2024) from the factory.

During startup I had dashes, colored stripes on the screen.
I downloaded new software from hugen79 in version 1.2.43.
I chose the NanoVNA-H-ZK 2.8-inch NanoVNA-H using SJWCH5351 as signal source, machine label hardware version ZK or SM_ST ending because nan SM_ST.
Did I do it right?
MODE ZEETK generator system has now appeared.
Should I stay on ZEETK or change to Si5351 or MS5351?

Hi

I think a 12Khz IF offset should be kept at default value and forget it , it gives the optimal Harmonic ratio filtering with the RC 1sft ordre low pass filter in the Hardware of nanovna

73's Nizar

I am learning about RF and antennas and I want to understand how do I figure out how much the IF offset is, in NanoVNA-H4. I could not find any article explaining how to check if the default IF OFFSET (12kHz) is accurate.

I also do not understand why its called an offset, since from what I read, this is the frequency that the VNA downconverts and uses it for receive-measure purposes. So it should say "IF", not "IF OFFSET".

After all if it was indeed an offset setting, it would be default to 0, not around 12kHz.

I first used a VNA when I was in Engineering within a National Broadcasting Network (CBC) and we used it for optimizing our transmitters and antenna systems. As a Young engineer it was an eye opener to see the physical display of and RF device, which prior to this was literally only a mathematical exercise. Carrying a VNA into the field was unheard of. Later when I moved on to a TELCO and became involved in the Cellular aspect go the RF Filtering and Antennas I had to design a carrying case to enable the carrying of the VNA into the field for compliance testing, all be it at the ground level. Now with the evolution of the NanoVNA you can literally take the device up the tower to the antenna in question. As a Field instrument the NanoVNA is a vast improvement which I see improving over time and becoming a much have in the Ham Shack as an indispensable tool. the capabilities of the NanoVNA will open doors which other wise were purely the domain of the skilled mathematician. Using the NanoVNA is literal proof of "Seeing Is Believing" type of device.

Hi All,

In the post title it says "what am I missing ?". Well, I now know what I missed - tapping the "Done" key when calibrating !

I am so used to calibrating my DG8SAQ and Sark 110 VNA's that I thought the NanoVNA worked the same. It would seem that, with those VNA's, exiting the calibration routine screen automatically applies the cal. Not so with the NanoVNA.

Observing that the load resistor was not measuring 50 ohms after what I thought was a correct calibration gave the clue - DUH !

Many thanks to those who gave their help.

73 Stewart G3RXQ

YouTube is your best friend!

Matthew
KD6KVH

It is a very powerful and useful device despite its size and cost. I have
used mine for many purposes including using the TDR function recently to
troubleshoot a feed line/antenna problem of a local FM station. I am also
using it to get an antenna system going for the 630 meter band. I myself
have never felt the need to connect mine to a computer. I just read what it
displays and write down any numbers I need.

On Sat, Mar 8, 2025, 8:07 PM Ryan Trullinger (KC0QNB) via groups.io
<rt83021@...> wrote:

I got my first Nano VNA yesterday, a friend who used to live 10 miles
away, now lives 1000 miles away bought it for me along with jumpers and
adapters. Today I set up "presets" for 80, 40, 20, and 2 meters.
I researched a bit and found out it could be a small SD card, all I had
was some 64-gig and one 16-gig card, well the 64 failed but I did manage to
format the 16 to fat32 and that just got finished can see this device is
going to be very handy, and a bit of a challenge, but that is OK. I have
always believed that learning is a lifelong experience, and if you stop
learning you stop living.
As I try to learn more about this thing, I am sure I will be visiting this
page frequently.

I got my first Nano VNA yesterday, a friend who used to live 10 miles away, now lives 1000 miles away bought it for me along with jumpers and adapters. Today I set up "presets" for 80, 40, 20, and 2 meters.
I researched a bit and found out it could be a small SD card, all I had was some 64-gig and one 16-gig card, well the 64 failed but I did manage to format the 16 to fat32 and that just got finished can see this device is going to be very handy, and a bit of a challenge, but that is OK. I have always believed that learning is a lifelong experience, and if you stop learning you stop living.
As I try to learn more about this thing, I am sure I will be visiting this page frequently.

QUOTE: You will do far better to connect the right most antenna and
collapse it

toa 1/4-wavelength at 433 MHz

Why do you say that ? Can't find the extensible antenna anyway.

***

Because the other two antennas shown in the image will not work well if at
all on 433 MHz.

The extendable antenna in the right-most antenna in the image.

Dave - W?LEV




On Sat, Mar 8, 2025 at 12:39?AM Roger Need via groups.io <sailtamarack=
[email protected]> wrote:

On Thu, Mar 6, 2025 at 03:38 PM, kellogs wrote:

You will do far better to connect the right most antenna and collapse

it

toa 1/4-wavelength at 433 MH

Why do you say that ? Can't find the extensible antenna anyway.

Because the antenna that is center loaded with a coil will have less gain
than a 1/4 wave marconi antenna.

--

*Dave - W?LEV*


--
Dave - W?LEV

Hi
What Smith measurements given with the reference load, the short circuit and open terminaison ??? It can help to better understand what can be the issue
73s Nizar

Hi Donald,

Thanks for that, it was pretty much what I was expecting, and ties in with what I am getting with my DG8SAQ VNA. I am also using a silver mica capacitor with about the same lead lengths. Also when using a a Sark 110 VNA I am able to get sensible readings. To get 11 ohms resistive just doesn't make any sense, and I am beginning to suspect that I have a defective NanoVNA.

Thanks for the info.

73 Stewart G3RXQ

Hi Stewart,

Out of grins and giggles I took a 470 pF silver mica cap which actually measured 454pf using smart tweezers. I then just used a test jig with my NanoVNA which was a white plug in experimenter board. Using an 18inch cable connected to my NanoVNA on one end and an SMA adapter on the other with 0.75 inch wires soldered to the SMA adapter that I plugged into my experimenter board. I then just did a simple open, short, load calibration in which the open was just that (complete open), then I used a short jumper wire plugged into the board, and then a 50 ohm resistor plugged into the experimenter board. I used a resistor with legs versus a nice calibration resistor that comes with the NanoVnA because I wanted the calibration to include the component legs (zero out the effects of the complement legs). I then measured my silver mica cap and it measured 845 m - 46.29 j ohms at 7.285 MHz which is pretty close to the Xc value of 48.12 ohms based on a 454pf cap. Pretty crude fixture but does a decent job at 7 MHz.

P.S. I’m using a NanoVNA-F V3.1

Just FYI,
Don wd8dsb

Uhm, right. This is over my head...

I was looking to find another impedance measurements for the said antenna, so I can check my measurements against. It looks to me unlikely to obtain such, so how about this:

use a few resistors after calibration and verify I am reading their resistance with 5% margin and +/-j10 reactance ?

I have done so with two thick film resistors, 24 ohm and 220 ohm; results are within the limits above. Call it good?

it depends ... what about a vertical 2x 5/8 wave ?? also with a loading coil at centre but with some gain over a quarterwave ... and cause its endfed it may be halfwave on 2m and 2x 5/8 on 70cm as dualband antenna its more or less ground independant (so called "earthless")

dgt9bfc sigi

Am 08.03.2025 um 01:38 schrieb Roger Need via groups.io:

I get accurate results when measuring capacitors with my NanoVNA so I assume it is something with your setup or calibration. Without photos or screenshots we don't have much to work with here.

Here is a measurement of a ceramic cap marked 485 pF that I made with a NanoVNA. I compared it to a measurement made with a DE-5000 LCR meter at 100 kHz. The estimate of Rs is poor under 500 kHz when the reactance is very high. But capacitance measurement is quite good.

Hi Jeff,

Yes, you are right about the strays of the test jig, and about the capacitor lead length. However, I am using the same test jig and capacitor that, although not perfect gives milli ohms resistance when using the DG8SAQ VNA and 11 ohms with the NanoVNA. So I am comparing Apples with Apples, and not with Oranges.

73 Stewart G3RXQ

Hi Stewart

Even at 7MHz it is unlikely that you will not be seeing some stray inductance and stray capacitance, so I am more surprised, at the 0 -j50 ohms. Unless your test jig is very good and the actual capacitor is leadless you are unlikely to get exactly 0 -j50 ohms.

73
Jeff G8HUL

________________________________________
From: [email protected] <[email protected]> on behalf of Stewart Baker <baker@...>
Sent: 08 March 2025 14:51
To: [email protected]
Subject: [nanovna-users] Smith Chart accuracy - what am I missing ?

Hi,

I am trying to get to grips why I am not getting the same Smith Chart results with my NanoVNA as I am with my DG8SAQ VNA. I have got to the stage of trying to make everything as simple as possible. I am using the same connectors, cables and calibration standards.

To make things even simpler I am just using a quality HV mica capacitor which measures 442 pf. According to Pasan software this should be 0 -j50 ohms at 7.2MHz. When I use the DG8SAQ VNA I get milli ohms -j46 ohms, which to me is close enough.

Using the NanoVNA with an identical setup I get 11 ohms -j49 ohms. Which is pretty useless. What is going on ?

T.I.A.

Stewart G3RXQ

Using the NanoVNA with an identical setup I get 11 ohms -j49 ohms. Which is pretty
useless. What is going on ?

Indeed 442 pF at 7.2 MHz, that's 0-j50 ohms No need for software to calculate that.
Z=1/Cw where
w=2*pi*F
C in Farad
F in Hz
pi 3.14

If with your NanoVNA you read: 11 ohms -j49 ohms, it's probably because you have badly calibrated your nanoVNA. You have to do OSL at the location where you place your capacitor
--
Fran?ois

-----Message d'origine-----

De la part de Stewart Baker
Envoyé : samedi 8 mars 2025 15:51

Hi,

I am trying to get to grips why I am not getting the same Smith Chart results with my NanoVNA as I am with my DG8SAQ VNA. I have got to the stage of trying to make everything as simple as possible. I am using the same connectors, cables and calibration standards.

To make things even simpler I am just using a quality HV mica capacitor which measures 442 pf. According to Pasan software this should be 0 -j50 ohms at 7.2MHz. When I use the DG8SAQ VNA I get milli ohms -j46 ohms, which to me is close enough.

Using the NanoVNA with an identical setup I get 11 ohms -j49 ohms. Which is pretty useless. What is going on ?

T.I.A.

Stewart G3RXQ