Hello Marv,
I can tell by reading your question that some of your understanding of how the Nano VNA works is not clear.
First the Nano VNA has two connectors they are referred to as Channel0 and Channel1
The Nano VNA has two operation modes, Refection and Thru
Cannel0 is used for reflection mode measurements
Channel0 and channel1 are used for thru mode measurements
Think of the two antennas as a two-port network. Measuring the insertion loss (S21) between the two antennas will give you the coupling from one to the other.
You only need the display set up for LogMag
There is no crossing of one trace to the other. The LogMag trace gives you the coupling between the antennas as a function of frequency.
I assume you are doing the correct frequency start stop set up and a full SOLT calibration
The previous reply showed you how to calculate the amount of power induced into the second antenna when 25 watts is present on the first one
Hope this helps clear up things for you.
73 Greg WA1JXR
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Thanks - that's exactly what I was looking for. Now I need to figure out how something like 1/10th milliwatt coming in on my ICOM IC-7300 receiver's front-end relates to its specs. Its sensitivity is about 1/10 microVolt.
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That would be 25 Watts minus 53 dB.
25 watts is 44 dBm
44 - 53 = -9 dBm? ?Or about? 1/10th milliwatt
Now you know why they like to keep the loops REAL close for inductive charging.
Kent WA5VJB
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On Thursday, June 30, 2022, 07:47:39 AM CDT, Marv <m207365@...> wrote:
I am trying to use my NanoVNA-H to see how much near-field coupling I have between two antennas in my backyard that are about 10 feet apart. I have one antenna connected to the S11 port and the other to the S21 port. I have S11 set to SWR and S21 set to LOGMAG. LOGMAG is -53dB at the point in the graph that both lines cross. I assume that is the amount of power being induced in the antenna connected to S21 by the antenna connected to S11.
Since the NanoVNA is only putting out a small amount of RF power, how would I relate that to for example transmitting 25 watts on one of these antennas and determining how much power is being induced in the other antenna?
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I am trying to use my NanoVNA-H to see how much near-field coupling I have between two antennas in my backyard that are about 10 feet apart. I have one antenna connected to the S11 port and the other to the S21 port. I have S11 set to SWR and S21 set to LOGMAG. LOGMAG is -53dB at the point in the graph that both lines cross. I assume that is the amount of power being induced in the antenna connected to S21 by the antenna connected to S11.
Since the NanoVNA is only putting out a small amount of RF power, how would I relate that to for example transmitting 25 watts on one of these antennas and determining how much power is being induced in the other antenna?
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In one of these threads someone mentioned the special SD formatting app that you can download for free, and in cases where you get strange behaviour you can always try that.
An SD card appears as at least one "drive" in many operating systems, but this is sort of a convenience rather than reflecting an actual mountable file system on the device itself. If you ever wondered why the advice for cameras and so on was to format the card on the device instead of using the OS tools, this is why. The SD format can be made to appear as a mounted file system on a modern OS, but it is actually a much different beast, physically. And some devices will refuse to recognize an SD card that has not been SD formatted because the SD format is quite specific to the hardware and software on the card.
Some devices just can't figure this out if the card has only been formatted using typical OS tools -- mostly because those tools do not actually do an SD level format. Most modern devices are more forgiving, but embedded devices (like cameras) have long had a problem accessing anything on the card unless it was formatted by the engine on the embedded device, which is a kind of format not at all like the one on the OS.
This is probably why factory fresh cards may work, but any older ones floating around in a box that has previously been written to by Windows may not always work in all devices.
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I had a write fail using a 16MB SanDisk, "properly formatted." Right.
A few days ago I received and tried the 16MB Patriot. It saved instantly, and without having to format it.
NanoVNA-H
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My question is it necessary to have the Nanovna set to the
frequency to be tested and calibrated before connecting to the computer and Saver
software? Hi I asked myself the same question as you. Obviously not: it is not necessary to calibrate the box before. You do with Calibration from nanovna-saver. I'm not smart enough to have known how to use the "normal" calibration so I do with the wizard. I assume that you have understood correctly that the short-circuit, open and load operations are to be carried out flush with the equipment to be tested; for example at the end of the aerial cable (by disconnecting the aerial). Without putting too much sweep in frequency, provides wide and with many segments (each of 101 bars). Note in the file name the frequency band and where you did the calibration. Nanovna-saver says nothing if later, your measurement band is not in the band used during the calibration. Obviously the measurements are then tainted with large errors. It is possible, with Excel, to correct the calibration file to smooth out the false (noisy) measurements. -- Fran?ois -----Message d'origine-----
De : [email protected] [mailto:[email protected]] De la part de Mike McKinney
Envoy¨¦ : mercredi 29 juin 2022 07:58
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I could not find any threads that answered this question so here goes. I have seen a lot of videos of calibration of Nanovna using the Saver program, some show calibration only in the program itself and others show calibration in the Nanovna prior to connection to computer and then in the program. My question is it necessary to have the Nanovna set to the frequency to be tested and calibrated before connecting to the computer and Saver software? I am primarily testing swr on homebrewed 2m and 70cm antennas for my own use. Thanks for any advice.
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Re: Updating firmware from linux
#linux
?
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On Tue, 28 Jun 2022 at 18:15, Chuck Miller <cwmiller20@...> wrote: Dragan, The problem was that both enteries were different memory areas of
the same device, so if I removed one, I removed both. The dfu-util -a 0 -D
firmware.dfu worked after I figured out I was missing the -a 0 part.
Thanks, Chuck
N0NC
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Re: Updating firmware from linux with the ST Micro CUBE programmer
#linux
Between that, and ST having end of life'd the dfu tool, at some point, it will likely become the only option. As other have noted, though, the idea of lean, efficient, *small* software appears to have died . . .
In any case, that's why I used Cube - the one product will work on many platforms. Huygen has .bin files of his distros, so all that is needed is for DSLord to drop .bin images as well as the .dfu (Since Cube can't read .dfu *files*, yet programs via the dfu *interface* . . .) Yeah, I could build to .bin, but am generally unmotivated to setup a build environment for this, since I don't plan to do NanoVNA development . . .
- Tim
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On June 28, 2022 12:35:00 PM CDT, Bob Snyder <bob@...> wrote: Thanks Tim. This appears to be quite comprehensive. I hadn't been aware that the Cube software was available for Linux, so this might come in handy in the future.
Bob Snyder
On 6/28/22 09:34, Tim Dawson wrote:
Here is the document that I had referred to showing how to update a NanoVNA with the ST Micro Cube programmer.
- Tim
On 06/27/2022 06:36 PM, Tim Dawson wrote:
I honestly don't know where it landed, and had asked if someone could put it on one of the pages so that it could be easily found, but I guess that didn't happen . . . I'll repost when I get back to my computer, and (hopefully) it can be put somewhere more easily findable . . .
On June 27, 2022 5:54:12 PM CDT, Bob Snyder <bob@...> wrote:
On 6/27/22 13:54, Tim Dawson wrote:
I use the ST Micro Cube programmer, and the .bin images from Huygen native on Linux and it works fine. (Search the group - I posted a full "HowTo" procedure a month or so ago). Tim,
Could you point to this post containing the howto? I don't see anything from you in this group regarding the cube software.
Bob
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
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Re: Updating firmware from linux with the ST Micro CUBE programmer
#linux
Thanks Tim. This appears to be quite comprehensive. I hadn't been aware that the Cube software was available for Linux, so this might come in handy in the future.
Bob Snyder
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On 6/28/22 09:34, Tim Dawson wrote: Here is the document that I had referred to showing how to update a NanoVNA with the ST Micro Cube programmer.
- Tim
On 06/27/2022 06:36 PM, Tim Dawson wrote:
I honestly don't know where it landed, and had asked if someone could put it on one of the pages so that it could be easily found, but I guess that didn't happen . . . I'll repost when I get back to my computer, and (hopefully) it can be put somewhere more easily findable . . .
On June 27, 2022 5:54:12 PM CDT, Bob Snyder <bob@...> wrote:
On 6/27/22 13:54, Tim Dawson wrote:
I use the ST Micro Cube programmer, and the .bin images from Huygen native on Linux and it works fine. (Search the group - I posted a full "HowTo" procedure a month or so ago). Tim,
Could you point to this post containing the howto? I don't see anything from you in this group regarding the cube software.
Bob
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Updating firmware from linux with the ST Micro CUBE programmer
#linux
Here is the document that I had referred to showing how to update a NanoVNA with the ST Micro Cube programmer.
- Tim
toggle quoted message
Show quoted text
On 06/27/2022 06:36 PM, Tim Dawson wrote: I honestly don't know where it landed, and had asked if someone could put it on one of the pages so that it could be easily found, but I guess that didn't happen . . . I'll repost when I get back to my computer, and (hopefully) it can be put somewhere more easily findable . . .
On June 27, 2022 5:54:12 PM CDT, Bob Snyder <bob@...> wrote:
On 6/27/22 13:54, Tim Dawson wrote:
I use the ST Micro Cube programmer, and the .bin images from Huygen native on Linux and it works fine. (Search the group - I posted a full "HowTo" procedure a month or so ago). Tim,
Could you point to this post containing the howto? I don't see anything from you in this group regarding the cube software.
Bob
--
Tim Dawson
972-567-9360
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Re: Updating firmware from linux
#linux
Dragan, The problem was that both enteries were different memory areas of the same device, so if I removed one, I removed both. The dfu-util -a 0 -D firmware.dfu worked after I figured out I was missing the -a 0 part.
Thanks, Chuck
N0NC
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Re: Updating firmware from linux
#linux
Do what the error message says, disconnect any other device and
update with: dfu-util -a 0 -D firmware.dfu
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On Mon, 27 Jun 2022 at 22:18, Chuck Miller <cwmiller20@...> wrote: Trying to update the firmware on my NanoVNA-H from linux got the DFU file
but keep getting error
dfu-util: More than one DFU capable USB device found! Try `--list' and
specify the serial number or disconnect all but one device
dfu-util -l
dfu-util 0.9
Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to
Found DFU: [0483:df11] ver=2200, devnum=10, cfg=1, intf=0, path="1-10",
alt=1, name="@Option Bytes /0x1FFFF800/01*016 e", serial="FFFFFFFEFFFF"
Found DFU: [0483:df11] ver=2200, devnum=10, cfg=1, intf=0, path="1-10",
alt=0, name="@Internal Flash /0x08000000/064*0002Kg", serial="FFFFFFFEFFFF"
all the instructions are for Windows and maybe Mac. Can't be done from
Linux?
Chuck
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Re: nanovna-saver/displayed charts/S11 R/¦Ø & X/¦Ø (?? / Hz)
I have compiled a version of Saver 3.10 that runs on WIN 7. You can download it from my
Roger Thank you very much Roger. It works now in 0.3.10 ¨C Win7 Already with the language, I have a lot of difficulty finding my way around in github. nanaovna-saver is a magic tool for me. I had a hard time figuring out what the baseline measurement the nanoVNA-F bridge was doing. Through nanaovna-saver I see that everything is recalculated from S11 since it is the only information that is available in the .s1p files I tried to install NanoVNA-WebApp-nightly-6e03c6c.apk on my tablet but maybe my system is too old: Model Number: SM-T530 Android Version: 5.0.2 Kernel version: 3.4.0-10239154 PS: I updated my profile -- Fran?ois (F1AMM) -----Message d'origine-----
De la part de Roger Need via
Envoy¨¦ : lundi 27 juin 2022 21:58
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Re: NanoVNA for RFID design
The ST rep said to just replace the short calibration of OSL with the coil attached. "short" calibration of the coil. Makes sense now in hindsight. Anyone have insight into the "conversion to 'Z: Reflection'" bit?
4. ¡°Short¡± calibration of the coil and conversion to ¡°Z: Reflection¡±
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Re: Updating firmware from linux
#linux
Ditto for me as well.
Thanks
Fred - n4cla
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On Mon, Jun 27, 2022, 18:54 Bob Snyder <bob@...> wrote: On 6/27/22 13:54, Tim Dawson wrote:
I use the ST Micro Cube programmer, and the .bin images from Huygen native on Linux and it works fine. (Search the group - I posted a full
"HowTo" procedure a month or so ago).
Tim,
Could you point to this post containing the howto? I don't see anything
from you in this group regarding the cube software.
Bob
|
Re: Updating firmware from linux
#linux
I honestly don't know where it landed, and had asked if someone could put it on one of the pages so that it could be easily found, but I guess that didn't happen . . . I'll repost when I get back to my computer, and (hopefully) it can be put somewhere more easily findable . . .
toggle quoted message
Show quoted text
On June 27, 2022 5:54:12 PM CDT, Bob Snyder <bob@...> wrote: On 6/27/22 13:54, Tim Dawson wrote:
I use the ST Micro Cube programmer, and the .bin images from Huygen native on Linux and it works fine. (Search the group - I posted a full "HowTo" procedure a month or so ago). Tim,
Could you point to this post containing the howto? I don't see anything from you in this group regarding the cube software.
Bob
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
|
Re: Updating firmware from linux
#linux
On 6/27/22 13:54, Tim Dawson wrote: I use the ST Micro Cube programmer, and the .bin images from Huygen native on Linux and it works fine. (Search the group - I posted a full "HowTo" procedure a month or so ago). Tim, Could you point to this post containing the howto? I don't see anything from you in this group regarding the cube software. Bob
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Roger Need
gfmucci
Mike McKinney
tjackson382000