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Thank you for the responses. I think I was unclear. What I am trying to understand is how one relates the marked value of a component to what nanovna shows. Using DL5FA’s item 8 inductor, my devices show 700 nH @50khz. But at 100mhz, the reading is 1uH. But the component is speced as 470nH, a value I can’t see anywhere, regardless fir frequency. How should I be reading this thing?
Thanks!
--
Ed K9EK

From: "Bob Albert via groups.io" <bob91343@...>
Date: February 12, 2021 at 6:36:54 PM PST
To: [email protected]
Subject: Re: [nanovna-users] measuring Capacitance or Inductance
Reply-To: [email protected]

? The inductance will change with frequency. I use the Smith chart and the resistance and inductance are displayed at the marker frequency.
Bob

The inductance won’t change with frequency (to a first order approximation and especially over a somewhat narrow range).

What will change is the reactance with respect to frequency.

XL= 2*pi*F*L
XC= 1/(2*pi*F*C)

The L and C values shown by the marker is calculated by solving for those values at a specific frequency (where the marker is set to)

Ray WB6TPU

Roger, Thanks for the suggestions. I have updated the firmware in my nanoVNA to v1.0.45 and everything is working fine now.
I would like to try the new NanoVNA app (Windows) by OneOfEleven, but I'm having trouble locating the Win 64 installation file.
I would appreciate it you could send me the link. Thanks, Geoff

The inductance will change with frequency.? I use the Smith chart and the resistance and inductance are displayed at the marker frequency.
Bob

Concerning how to measure capacitance and inductance on the RF Demo board (or any capacitor or inductor), reference /g/nanovna-users/wiki/16592. I can get the curves shown in this demo just fine.. but how to read the actual values off of those curves eludes me. On the item 8 inductor example, if I vary the frequency, I can make that component read about any value I want. I must be missing something. Help, please.
--
Ed K9EK

On Fri, Feb 12, 2021 at 01:05 PM, gmendenh1947 wrote:

Roger, I wanted to try the new features in v 0.8.0-20200620 released on Jun
19, 2020 by edy555 including the contributions of DiSlord.
I posted looking for a solution and if it is a bug, I wanted to let edy555
know about it.

I can always revert back to v 0.2.3-2, Oct 18, 2019 if necessary unless you
can suggest a newer, bug free version.

Why not try the latest version by DisLord (1.0.45) in the files section of this group. Some nice enhancements and it works with the new NanoVNA app (Windows) by OneOfEleven which has more features than NanoVNA Saver.

Roger

Sweeping normally. This is not the problem

Roger, I wanted to try the new features in v 0.8.0-20200620 released on Jun 19, 2020 by edy555 including the contributions of DiSlord.
I posted looking for a solution and if it is a bug, I wanted to let edy555 know about it.

I can always revert back to v 0.2.3-2, Oct 18, 2019 if necessary unless you can suggest a newer, bug free version.

Thanks,
Geoff

Hello Frank,

I do not have a BOM, but some documentation:
/g/nanovna-users/wiki/16592

73, Rudi DL5FA

Stimulus menu - pause sweep

Hello,
I am having trouble finding a BOM and schematic for the NWDZ Rev-01-10 RF demo kit kit with google. I have the board with the LPF 30MHz on the top left corner. Could someone point me towards that?

Just to be clear I have this version:


Not this version:

Thanks,
Frank


Frank

Why not try using Hugen's last firmware release or the one by DiSlord

Roger

SWR readings are normal using nanoVNA Sharp v1.02 on PC using USB interface, but nanoVNA SWR trace at bottom of screen with marker showing 1.0003:1 when actual SWR is 1.5:1

My current configuration is attached.

I just updated my nanoVNA to version 0.8.0-20200620 firmware. After going through calibration the Return Loss, Insertion loss, and Smith traces all worked normally, but the SWR trace is stuck as a straight line at bottom of the display regardless of scale settings or return loss on CH0 port. Any suggestions on how to fix this?

You are welcome. I am glad you had success. YouTube is also a great
resource for this kind of thing in addition to many many other things. It
is the second most popular "search engine" for a reason. I assume you do
not use it?

--
Kamryn Kant
Graduate Student
Dept. of Chemical and Biomolecular Engineering
Clemson University, Clemson, SC 29634
*[email protected] <[email protected]>*

GM and Thanks. After looking into that page there is one thing caught my eye that no other documents said to do. Hold down the thumb wheel and turn the unit on, it goes into UDISK mode and you just dump the new .bin file on the unit. Turn it off and back on and it loads the new firmware. Now running 1.4.

Thanks 73
Bob

OK, thank you very much for all info DiSlord.

Regards,

Jos


Op 12-2-2021 om 05:06 schreef DiSlord:

I just learned how to take an S21 measurement at HF frequencies.

I used a 1960's Drake "Low-Pass Filter" (52 ohm in/out) that reduces the higher harmonics of HF rigs.
It used to be called the "TVI" (television interference) filter.
The 1950-1990 tube type HF rigs had a pi-network tuner and some had considerable harmonic output, which obviously got into the older analog TVs. That was often a BG problem back then.

Drake says their filter had 80 dB attenuation above 41 MHz.
My Nano VNA confirmed that presisely down to -80 dB on S21.
But the data looked noisy at that level.
I guess the issue is what DYNAMIC RANGE does the Nano VNA have and at what frequency.
I had the display stop at 100 MHz.

I have enjoyed getting to "know" this gadget.

Barry k3eui

Hi David,

See message # 896, the pdf and then go to page # 6 in that document. A sample of the document below. Please note the RESET command, item 18. Your RESET command as part of a soft key function should be there. No PC etc... required. Source is original firmware from 2019.


Tap the screen again and continue.
13. STIMULUS
14. START 50 kHz.
15. STOP 900 MHz.
16. BACK
17. CAL
18. RESET
Note 10:
Invoking the RESET command at this point is key to a proper calibration sequence. The RESET
button will highlight and stay highlighted. Invoking the RESET function will destroy all the
previously saved calibration data. It is now imperative that this procedure run to completion to
generate new data. Now continue.
19. CALIBRATE