Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- Nanovna-Users
- Messages
Search
|
Re: NanoVNA App - Installation and Use
#applications
V2Plus4 on original fw not supported by NanoVNA-App (as i remember, Owo not want fix several things in firmware for support)
Need fix several problems in exchange protocol on V2Plus4 side (or fix NanoVNA-App) My fw for V2Plus4 allow work vs NanoVNA-App, but not support last V2Plus4 hardware (different LCD module). I suggest use NanoVNA-QT, this software created for V2Plus4, and support by designer. |
|
Re: NanoVNA App - Installation and Use
#applications
GMRS_two_way_radio
Hi
I tried to post a topic on the problem i am having but it hasnt been approved yet :( I am having problems (i can't calibrate) with OneOfEleven NanoVNA-App, I am using the nanoVNA V2 plus4 model maybe its not compatible with that model. here is what i have done so far: re-installed USB driver I tried 2 other computers, same problem ( Windows 8.1 and Windows 10) I tried another USB cable here are two videos so show what is going on: part 1 video: part 2 video: any help would be great! thanks |
|
problems with OneOfEleven NanoVNA-App
GMRS_two_way_radio
Hi
I am having problems (i can't calibrate) with OneOfEleven NanoVNA-App, I am using the nanoVNA V2 plus4 model maybe its not compatible with that model. here is what i have done so far: re-installed USB driver I tried 2 other computers, same problem ( Windows 8.1 and Windows 10) I tried another USB cable here are two videos so show what is going on: part 1 video: part 2 video: any help would be great! thanks |
|
Re: Antenna Gain measurement with NanoVNA
Michael Black
Are you measuring at the antenna?
toggle quoted message
Show quoted text
You can't measure SWR accurately at the rig unless your antenna is zero reactance at 50Ohms. Mike W9MDB On Tuesday, August 23, 2022 at 01:01:10 PM CDT, W0LEV <davearea51a@...> wrote:
A dipole, by definition, is resonant:? +jX = -jX = 0. A doublet is a dipole, but not resonant where you require. My 450-foot doublet exhibits its first 1/2-wavelength resonance at roughly 950 kHz, but does not show resonance in any of the HF ham bands. Yes, measurements need to be made to reduce / minimize unwanted reflections.? That's the devil in the details. Dave - W?LEV On Tue, Aug 23, 2022 at 5:54 PM Roger Need via groups.io <sailtamarack= [email protected]> wrote: On Tue, Aug 23, 2022 at 10:13 AM, W0LEV wrote:--over *Dave - W?LEV* *Just Let Darwin Work* -- Dave - W?LEV |
|
DiSlord v1.2.0 instability even though MS5351 clock-generator is selected (MS-3.6 HW version)
Hi guys.
My original NanoVNA-H genuine (sourced from Eleshop in EU) has been working flawlessly with delivered 1.1.01 synchronised DiSlord firmware. After upgrading to DiSlord version 1.2.0 and selecting Ms5351 clock generator in options give severe signal error in around 420M-440Mhz and 600M something. Even reverting to Si5351 setting and back again as well as resetting all settings and creating completely new calibrations does not solve it. Only remedy is to revert back to 1.1.01 DiSlord synchronised version but then I miss all the new trace formats and especially the ability to flip screen. Anyone know if there will be a DiSlord synchronised 1.2.0 version with MS or SI selectable initial clock generator setting? Thanks C |
|
Re: Antenna Gain measurement with NanoVNA
On 8/24/22 1:46 AM, F1AMM wrote:
M1 = Gunk * Gref1 Yes, the antennas are mounted in the same positions, relative to each other, for all measurements. The reference antennas can be dipoles. There's no need for all 3 antennas to have the same (approximate) gain. This was for a "nose to nose" gain measurement. If you need to do a radiation pattern, it gets trickier. Essentially you calibrate the "probe" antenna with a duplicate at known range. if you want to measure radiation patterns, then reflections and such becomes a bigger issue. |
|
Re: Antenna Gain measurement with NanoVNA
F1AMM
M1 = Gunk * Gref1
toggle quoted message
Show quoted text
M2 = Gref1 * Gref2 M3 = Gunk * Gref2 This assumes that Gunk Gref1 and Gref2 are constant during the three measurements. I do not see at all how one can fulfill this condition already because of the directionality of the antennas. Or do you suppose that it is, for example, 3 yaggi that we reorient in the axis of each measure? -- F1AMM (Fran?ois) -----Message d'origine-----De la part de Jim Lux 24 ao?t 2022 03:24 |
|
Re: Antenna Gain measurement with NanoVNA
On 8/23/22 1:59 PM, Donald S Brant Jr wrote:
NBS (now NIST) published the dimensions of a reference dipole for such uses: 2 1¦Ë dipoles above a 1.6¦Ë x 2¦Ë ground plane. Built properly it should have gain accurate to a few tenths dB or less at the design frequency.It's also in the ARRL Antenna book. But in reality, you can build two identical reference dipoles in almost any configuration (they don't even have to be resonant or matched to 50 0 ohms) and do a three cornered hat to remove the common term. Let Gunk be the gain of the unknown. Let Gref1 and Gref2 be the gain of the reference antenna Make three measurements at the same distance, with each possible pair. M1 = Gunk * Gref1 M2 = Gref1 * Gref2 M3 = Gunk * Gref2 M1*M3/M2 = (Gunk^2 * Gref1 * Gref2)/(Gref1 * Gref2) = Gunk^2 So Gunk = sqrt (Gunk^2) Doing it in dB is easier, of course. This doesn't account for ground bounce, reflections, etc. - That's another technique. |
|
Re: Bug or fubar'd upgrade?
#firmware
Cliff
Cool! Seems to work fine here on MacOS.
toggle quoted message
Show quoted text
73, Cliff, AE5ZA On Aug 23, 2022, at 19:15, Tim Dawson <tadawson@...> wrote: |
|
Re: Bug or fubar'd upgrade?
#firmware
FYI, the python based tool at appears to pull perfect binary images out of the NanoVNA .dfu files found on Huygen's site (checksums the same as his .bin files).
toggle quoted message
Show quoted text
The best news is that it is tiny, and being Python based, should work on any platform - Mac, Win, *nix - and allows the use of the ST Micro recommended Cube programmer tool FWIW . . . ?- Tim On 08/23/2022 02:37 AM, Ho-Ro wrote:
On Tue, Aug 23, 2022 at 08:58 AM, Ho-Ro wrote:To build the FW ... just type "make" and "make flash",Default is -H, for -H4 the command is --
Tim Dawson 972-567-9360 |
|
Re: Antenna Gain measurement with NanoVNA
Using the substitution method in measuring emissions from equipment for
regulatory purposes, a dipole and a signal generator is used. There many reference dipoles out there to be had on the used market. I have several. They are also easy to make, but be sure to decouple the feedline with a number of ferrites of appropriate mix. Page 25 of the First Edition of J. D. Krauss *ANTENNAS* may also be useful. While it won't get you the closest 0.1 dB, it offers a simple method without using a reference antenna. [image: image.png] I'll also attach the page in case this group does not support in-text images. Dave - W ?LEV On Tue, Aug 23, 2022 at 8:59 PM Donald S Brant Jr <dsbrantjr@...> wrote: NBS (now NIST) published the dimensions of a reference dipole for such-- *Dave - W?LEV* *Just Let Darwin Work* -- Dave - W?LEV |
|
Re: Antenna Gain measurement with NanoVNA
NBS (now NIST) published the dimensions of a reference dipole for such uses: 2 1¦Ë dipoles above a 1.6¦Ë x 2¦Ë ground plane. Built properly it should have gain accurate to a few tenths dB or less at the design frequency.
The EIA published a similar standard gain antenna, shown in 5.2.5 of this document: The paper also has good information on antenna gain testing. 73, Don N2VGU |
|
Re: Bug or fubar'd upgrade?
#firmware
Cliff
Roger,
toggle quoted message
Show quoted text
Worked great. Now I have to figure out the extra menus, but that's to be expected. Thanks so much for the file. Maybe it could be uploaded to the file section of the group for others to use if they wish? 73, Cliff, AE5ZA On Aug 23, 2022, at 13:26, Roger Need via groups.io <sailtamarack@...> wrote: |
|
Re: Antenna Gain measurement with NanoVNA
Thank you for your reply. Very interesting.
toggle quoted message
Show quoted text
Fred - N4CLA On Tue, Aug 23, 2022 at 3:23 PM W0LEV <davearea51a@...> wrote:
QUOTE: " Just out of curiosity, why would you want a 450 ft doublet |
|
Re: Antenna Gain measurement with NanoVNA
No, Jim, absolutely no attempt to ever consider measuring the "gain" of my
toggle quoted message
Show quoted text
450-foot doublet!!! At best, I model it using 4NEC2 and even that with a large crystal of salt. Measuring the gain (directivity?) of an antenna applies to VHF and above! HF? Do the modeling. But, then, the NEC code does a miserable job of handling "ground" (earth). Dave - W?LEV On Tue, Aug 23, 2022 at 7:08 PM Jim Lux <jimlux@...> wrote:
On 8/23/22 11:00 AM, W0LEV wrote:--A dipole, by definition, is resonant: +jX = -jX = 0.roughly *Dave - W?LEV* *Just Let Darwin Work* --
Dave - W?LEV |
|
Re: Antenna Gain measurement with NanoVNA
QUOTE: " Just out of curiosity, why would you want a 450 ft doublet
toggle quoted message
Show quoted text
resonant at 950 kHz?" Just to install as much wire in the air as is reasonable. I could string well over a couple thousand feet, but ....... We live on 40-acres in Northern Colorado in the foothills of the Rockies. So, why not? It is fed with parallel conductor XMSN line, a robust (home brew and meticulously characterized) common mode choke (actually several, depending on frequency) and an over designed (again, pretty robust) L-Network matching network (a.k.a., "antenna tuner"). An antenna or set of wires doesn't have to be resonant where one desires to be a good radiator/receiver of RF energy. I use these wires from 630-Meters (with additional inductance) through 6-Meters. I also have an NVIS 40-meter dipole and a 6-Meter inverted Vee on the hillside, but seldom used. Most of the antennas are for radio astronomy and/or ionospheric profiling (mainly E-Layer). Dave - W?LEV On Tue, Aug 23, 2022 at 6:15 PM Fred Moore <n40cla@...> wrote:
Good afternoon Dave.-- *Dave - W?LEV* *Just Let Darwin Work* --
Dave - W?LEV |
|
Re: Antenna Gain measurement with NanoVNA
On 8/23/22 11:00 AM, W0LEV wrote:
A dipole, by definition, is resonant: +jX = -jX = 0.You're not going to be measuring the gain of a 450 foot antenna with a NanoVNA. The OP was for a printed circuit antenna, presumably well above 100 MHz. The fundamental problem will be the free space loss. Let's assume isotropes for the moment. Let's further assume that the probe/reference antenna is 5 wavelengths away. At 300 MHz, that's 5 meters. Loss = 32 + 20*log10(0.005) + 20 *log10(300) = 32-46+50 dB = 36 dB loss. So that's plausibly ok - your S21 readings will still be big enough that the uncertainty due to SNR won't be too bad. And you can measure that in a backyard range. You need to move the probe up and down so that you can quantify the "ground bounce" contribution. By the way, the usual guideline for antenna test distance of 2*D^2/lambda isn't really valid for low gain antennas. But if you take D as 1/2lambda, you wind up with 2*0.5^2 * lambda^2/lambda which is 1.4 lambda. |
|
Re: Bug or fubar'd upgrade?
#firmware
Cliff
Hey Roger,
toggle quoted message
Show quoted text
Thanks a bunch! I'll give it a go and let you know how it went. 73, Cliff, AE5ZA On Aug 23, 2022, at 13:26, Roger Need via groups.io <sailtamarack@...> wrote: |
Donald S Brant Jr
to navigate to use esc to dismiss