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Jittery , non steady readings
8
Is it normal for the readings to fluctuate as much as 2-3 ohms ? As in 11+/-1.5 - j(70+/-1.5) Dipole NMHA (antenna), balun, calibrated, two ferrites: one at the balun and one at the VNA S11 port. No body / coax inadvertent movements, everything taped down near the antenna. Thanks
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I buyed a nanovna H 3.6. When I try to calibrate it, after the full procedure, if I set a Smith diagram and I connect THRU the two ports using the supplied cable the value is 50 ohm instead of 0. I resetted and repeated the calibration a lot of time but with the same result. Can you help me? Thanks
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Electrical 1/2 wave.
5
I have a NanaVNA-H4, And how would I use it to make an exact 1/2 wave or multiple there-of coax? 1/2, 1.0, 1.5, 2.0, etc... Joe WB9SBD
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NEgative resistance for S11 port antenna measurement
4
Hello, v0.7.3 on Windows; Already had my nanovna calibrated in two range: 30 MHz around 315 and another 30 MHz around 434; used an average of 10 sweeps with ~saver which has produced some partly negative values for resistance - measured two (almost) identical antennas, without any in- ~saver calibration. I can say for sure that nanoVNA did not report any negative resistances. Having seen the failure, i have then set an interval from ~225MHz to 525MHz, some ~300 points, calibrated inside ~saver, remeasured the two antennas with generally different results, but still having ranges of frequency where the resistance was again negative. I have not properly checked what the naonoVNA was reporting on its screen for the frequency range. What am i doing wrong ? Thanks!
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New HW version 3.6.1 observations and questions
6
There is a new HW version being sold now. I purchased my unit from one of the recommended sellers on the NanaVNA site. (Aursinc on Amazon) The new version has a different clock generator SMC5351A. Not sure how it compares to the original Si5351, or the supposedly better MS5351. (I know the switch to MS5351 was de to availability, but it was claimed that it had slightly better performance over the Si5351) I had a lot of trouble finding any info on the new chip, and no proper data sheet. Did find a little information, but not enough to do any comparisons, and I am not an expert in this aspect anyway, so subtle differences would be lost on me. Not sure why the change to this new part, as it forks the FW to yet another version, and this particular nuance of the FW update process is not well documented. Not even any of the newer instructional videos online mention it. The fact that the documented application DFUSE has been replaced by STM32CubeProgrammer, and also that the new DFU driver does not work with DFUSE is also not documented. I was able to do the FW update using the same method as the TinySA... Which also does not work as various instructions online show. I must use the "Full Chip Erase" command first, then load the new FW onto the device, otherwise the unit will not boot. This posed a problem for me, when I attempted to update the FW to the latest DiSlord version. The unit booted, but the screen was jumbled. After loading the SM_ST version from hugen79, things are back to working. This FW is a version behind DiSlord's, so hopefully they get an update for this new HW revision soon. The only question I have now, is which mode under Expert Settings I should use. MS5351 or Si5351 It appears to default to MS5351, so that is probably what it should be set to.
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Buying new VNA
13
Hi guys, this is my first post here, I would like an advice to buy a new VNA, my main operation is till 50MHz, but eventually I can operate till 1.2GHz, what would be a good VNA to buy, H4; F; SAA. Can anyone recommend one. Thanks Nuno CT2IRY
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red LED no longer lights
3
I have updated the firmware on my nanoVNA-H4 hardware build 4.3 using the NanoVNA-H.v1.2.40.bin file and STM32cube software, and notice that the red battery LED no longer lights when charging or unit is turned on. Same effect after I upgraded my TinySA Ultra....no longer red LED function. Is that normal?
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Running NanoVNA Saver (or other software) on Linux
10
Have been searching the threads for this item and am wondering if.. (1) NanoVNA Saver has a port to Linux or can be run under Wine on Linux? (2) Are there any other NanoVNA software packages that run under Linux? Thank you in advance. -- William, k6whp -------------------- "Cheer up, things could get worse. So I cheered up and things got worse."
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Locked
McAFee Virus Scanner Objects to nanoSaver download from GitHub
16
I've tried downloading nanoSaver to Win11Pro and McAfee snatches the .exe into quarantine. I'm using the github download: https://github.com/NanoVNA-Saver/nanovna-saver/releases I tried using a Win10 machine and nanoSaver runs, but MacAfee wants to remove a virus. Anyone got a clue on what is going on?
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* * * * * Multi-Band HF Vertical* * * *In an effort to get a VERTICAL ANTENNA up for the 20/17/15/10 meter bands, I tried setting up a 14 ft vertical antenna* *made from old aluminum tubing, mounted 3 ft above ground, adjacent to a 20 ft vertical aluminum rain gutter - mounted just inches from it for close coupling.* *Set up three radials - two were 13 feet and one was 33 ft. **No matching of any kind.* * * *Results were surprising as the rain gutter makes this vertical into a reasonable multi-band vertical for 20/15/10 meters. * *Cost was almost nothing.* *Fed with 50 ft of RG8X and a coax choke at the input to the antenna terminal.* *I'll have to try it out this weekend on 20/15/10m digital and see if it radiates a low-angle DX signal.* *de k3eui barry*
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Hello, new to this group. I've learned a lot from reading here, but i seem to have run into some issues and could use some advice. I'm building a low pass filter, and trying to learn to measure inductance using the nanovna. I've built a test rig that I found on one of the threads here somewhere- three pieces of double sided pcb for OSL, and I'm soldering my air core inductors to that. I'm trying to use the S11 shunt method for a coil that needs to be 72.4nH. Ive got a couple things I'm not understanding- should my coil be adjusted for the necessary inductance at the frequency for the filter of 50-55mhz? And does it need to be adjusted for impedance at that band as well? I've attached photos- my 90deg phase and 50 ohm mark is at 112mhz, but this inductor is for the 6m filter. Another thing I'm not understanding is the 5khz self resonance dip seen at the beginning of the sweep, shouldn't it be reading capacitive since it's after the phase reversal? Any help is appreciated
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Apologetic Intro Message
12
Just joined and here goes my newbie message. Sorry. (1) I have an H4 from 2020 with the 0.5.0 FW version. I am guessing that an upgrade would be in order? (2) Also looking into an "F" and saw some being sold on AliExpress for 102.93 marked down from $205.86 (50% off) ..is this a reliable source and product (link below) or, in not, what is reliable? Thank you in advance. -- William, k6whp -------------------- "Cheer up, things could get worse. So I cheered up and things got worse." https://www.aliexpress.us/item/3256806945598446.html?spm=a2g0o.productlist.main.15.7d601593PWjk7F&aem_p4p_detail=202503180111544540975407725520000030587&algo_pvid=db65f088-f2d8-475b-a4b2-eb0ecb9c50a0&algo_exp_id=db65f088-f2d8-475b-a4b2-eb0ecb9c50a0-7&pdp_ext_f=%7B%22order%22%3A%221%22%2C%22eval%22%3A%221%22%7D&pdp_npi=4%40dis%21USD%21205.86%21102.93%21%21%211480.98%21740.49%21%40210312d517422855142704518e4a59%2112000039530167557%21sea%21US%213368703417%21X&curPageLogUid=2arQ5G1GtJBb&utparam-url=scene%3Asearch%7Cquery_from%3A&search_p4p_id=202503180111544540975407725520000030587_2
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Hi, Is my setup ok ? Is there any monstrous mistakes in my montage ? I'm quite new to the nanoVNA. Well, I am totally new on VNAs themselves. I did not know their exitance 2 months ago ! Well, I want to match my antenna because so far, it is pretty horrible. But, before ordering some matching network component and then screwing everything because I am missing something obvious, I would like someone to point me to the rookie mistakes I could have made. The project is a LoRa module (902-928MHz) connected to a small antenna mounted on a pcb. The pcb is inside a small polycarbonate box. I have followed the design rules for this antenna from the manufacturer. I have calibrated my nanoVNA-F V2 (from sysjoint) using the supplied calibration set, straight at the S11 connector. My board is inside its final box and mounted on a wood plank that mimic the final location. My board is hooked up to the vna through an RG-174 I had laying around. It is 2 meters exactly. I have added an E-Delay of 10.1ns as per a calculator I found on the Times microwave website. I don't know if there is a bug in the vna's firmware but I had to put 0.66 as the velocity factor in order to make it display 2.00 meters as the cable length. If I put 66 as in 66%, it shows 200 meters. Anyways, I'm not sure if that part is that relevant. So, by looking at the pictures, does anyone can see some obvious mistakes ? Thank you so much
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New user (owner) of Nano VNA
5
Hey guys just got a nano VNA. it is a "seesii, nano VNA-H. I need some help in setting it up to see the SWR on some antennas. I have gone through the various manuals and the one that came with it, and I am very confused. Basically what I am looking to do is (to me ) very simple. Input a start frequency, lets say 144 MHz. A stop frequency, say 152 MHz. The see the lowest SWR point as an inverted bell curve. Anyone have any ideas how to do this? Also, I cannot seem to find the correct software for the device. I know my cable is good (as I can get data off my cell phone with it) but i cant the nano VNA to be recognized. Please help. Howard
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What we can do more with TinySA ultra
4
Hi As a hamradio operator what can i do better with TinySA ultra then NanoVNA H4 ? What kind of measurement with TinySA can be really usefull for antenna, filtering .. around hamradio activity , did sdrplay spectrum display can replace TinySA on moste cases ? i see that it has a handy signal generator but what really much important to do with? 73s Nizar
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Haven¡¯t bought one yet but I¡¯d like to make sure I get a version capable of the TDR addition. I¡¯ll have to figure out how to add it if necessary after receiving it. Thanks.
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.NanoVNA-H v3.5_L: white screen - how do I connect USB to fix?
10
I couldn't connect to the unit and somehow managed to wipe the processor. I've tried resetting it to reconnect, but the only response I get is in STM32Cube Programmer 'UR is set by HWrst' or something similar. I tried shorting BOOT0 to VDD as noted, screen remains white, no connection. Any suggestions would be appreciated!
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I have been using my nanovna SAA2N for months without issues, and I bought it from R&L who is an authorized distributer of legitimate Nanovna's. This morning my issue started after I calibrated the unit. All of my traces were erratic (see attached picture). Smith chart is a mess of zig zags instead of arcs. I tried the following and nothing has fixed the issue. "Reset" and "Reset All" prior to calibration. Tried multiple frequency ranges and trace points. Tried using both cables. Tested the cables for shorts/continuity. Tested all three standards (short, open, load) with an ohm meter, unfortunately I don't have another set to try. Flashed the firmware. Opened up the case and confirmed good solder joints and continuity from the N connectors to the board. Wiggled the connections and nothing changed. Checked again when the battery was fully charged. Also tried using VNA View and got the same results. The unit was safely stored in the case between the last time it worked and now. What am I missing?
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A ham friend has an unusual indoor antenna that he uses with a Zachtek WSPR transmitter. He gets lots of spots from the 200mW transmitter (>500 unique band/spotter combinations in 24 hours), and the beauty of the Zachtek is its tolerance of essentially any antenna load (from nothing attached to fully shorted). His antenna is effectively an off center fed dipole, where the two wire legs wrap around the inside bedroom walls, and are of random/different lengths..i.e .just whatever would fit onto the four walls. The two dipole legs are connected to a simple 6:4 turn ratio transformer (approx. 2:25:1 impedance ratio), with the primary side of the transformer attached to a 4 ft coax feedline line to the Zachtek transmitter. I decided to make some measurements of the SWR with the nanoVNA attached to this "creative" antenna setup. The nanoVNA was OSL-calibrated, followed by attaching the antenna feedline to collect data in nanovnasaver software. After collecting the data, I decided to reverse the two dipole legs connected to the transformer secondary, just to make sure I was getting reproducible data. What confused me were significant differences in the SWR/return loss/Smith charts for the two configurations. I am wondering if this simply reflects how non-balanced the dipole is, such that the coax feedline shield (about 4 ft long) from the transformer plays a different role in each of the two configurations. While making the measurements the nanoVNA was dangling hands free while connected to the USB port on my laptop...so the coax shield side would be the same in both cases...and the only electrical difference was in reversing the dipole legs (of differing lengths) connected to the transformer secondary.
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I recently wrote a program to renormalize S-parameter impedance. This lets you measure a filter with a 50 ohm VNA even though the design impedance is higher. In the course of testing the program, I needed to plot S-parameters. I searched extensively for suitable viewers, desktop or online. The ones I located were either incomplete, frustratingly awkward, or had bugs. I decided to write my own Windows S-parameter plotter. It's near the top of the following page. See the bottom of the page for downloading instructions. http://ham-radio.com/k6sti/mu.htm The first image compares group delay for two Murata ceramic filters. The next images show the benefit of phase unwrapping. Brian
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Sat 8:39am
Sat 8:39am