Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [nanovna]

12 questions
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Using a Return Loss Bridge and Nano VNA to measure amplifier characteristics

One of the difficulties of measuring active devices like LNA and IF amplifiers with the Nano VNA is the care needed to avoid over-driving the amplifier input and, more importantly perhaps, to avoid blowing up the CH1 port during S21 (gain)…
Buck8pe
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Measurement of antenna with VNA does not match its specs

I have a NanoVNA V2 Plus (50kHz - 3GHz) and decided to test my LoRa antennas: an unknown antenna delivered with a LoRaWAN gateway (RAK831) a 868Mhz antenna from Linx Technologies (ANT-868-OC-LG-RPS) As the range was poor between my gateway and my…
DurandA
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Using NanoVNA to tune antenna

I'm extremely new to this, so I'm mostly asking for tutorials and so on. I have tried configuring the device according to one tutorial I found. When I hook up the cheap antennas that came with a couple of my radios. I could see the attenuation dips…
Jesse Knott
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Why would a VNA not make a good Spectrum Analyzer? Or an SDR a good VNA?

Happy to be corrected where I'm wrong in any of this but in broad strokes my understanding is: Spectrum Analyzer measures input signal strength while sweeping across frequencies, measuring RF emissions often includes "tracking generator" to output…
natevw - AF7TB
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Measuring actual feedpoint impedance for a given frequency

Background I'm attempting to tune an antenna with my NanoVNAv2. I calibrated it using the included open/short/(50-ohm)load standards by screwing them directly onto the NanoVNA one by one and running its calibration function. The antenna itself is a…
Bitbang3r
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Can you think of any reason my NanoVNA says my antenna has 1.2 SWR while my radio says it has off the scale SWR?

My radio is an mcHF kit that I just finished soldering up. It receives fine, but when I went to transmit it's giving off the scale SWR. I rechecked my antenna with my NanoVNA, and it shows 1.2 SWR at the same frequency. I would say there's a fault…
rcx935
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NanoVNA(v2)... what to capture for future reference when comparing past antennas?

I'm designing a HF antenna that uses a portion of a downspout (electrically isolated from the gutters above and lower portion) as a bottom-loaded shortened quarter-wave vertical. I'm about to trim the downspout down to what I'm planning to use as…
Bitbang3r
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Saving snapshot of NanoVNA (v2) data for later review, analysis, comparison, etc

I have a NanoVNA (v2), and I'm using it with vna-qt. I want to capture the raw data from a sweep for posterity, so that I can someday compare different antenna variants for things like SWR, resonance, etc. I'm pretty sure vna-qt itself can't load…
Bitbang3r
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Why does SWR of a dipole decrease the closer it is to the ground?

I experimented with a 20m dipole made of a 1:1 balun connected to 2x ~5-meter lengths of copper wire, running parallel to the ground (by "ground" I mean "pavement", not quite the electrical ground). I wanted to make sure that placing it higher is…
JayPulsar
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How to determine if filter is well matched?

Hello i'm in process of creating band pass filters for my ham radio. I calculated the filter for 80m band basing on this website: And recreated it in reality: Then I started measuring it with nanoVNA, and tuning the trimmers to get best frequency…
fifi_22
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Is this amount of loss normal with LMR400?

I have a run of about 150 feet of LMR400 (specifically, it's this DX Engineering "400MAX" product). It connects to an Ed Fong antenna (2m, 1.25m, 70cm tri-band J-Pole) about 75 feet up a tree. Here's what the SWR for the antenna looks like when…
User5754448
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How do I configure a NanoVNA v2Plus4 to check a 1:1 Balun?

Note that the menus are different than those I'm seeing on YouTube which aren't for the V2plus4. What's missing is "Isolation" and of course, there is an additional standard for that which is also not included with this device. Specifically, the…
NonYaBidnezz
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