NanoVNA-H4
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| Frequency | 10 kHz - 1.5 GHz |
| Bands | VLF through UHF/low microwave |
| Power | Two-port vector network analyzer — test instrument |
| Modes | S11 (reflection: SWR, impedance, return loss, Smith chart), S21 (transmission: insertion loss, filter response, cable loss), TDR (time domain reflectometry with software) |
| Weight | 360 g (12.7 oz) |
| Year | 2019 |
| ch0 | SMA female (port 1 - reflection/S11) |
| ch1 | SMA female (port 2 - transmission/S21) |
| usb | USB-C (charging, PC/Android connection, firmware update) |
| power req | Built-in 1950 mAh Li-ion battery (USB-C charging, ~8 hours use). Also operates from USB 5V. |
A two-port vector network analyzer for a fraction of what VNAs used to cost. It measures SWR, impedance, resonance, cable loss, filter response, and more. The battery-powered touchscreen is fully portable. NanoVNA-Saver PC software turns it into a serious analysis tool with data export, and a calibration kit is included. Equivalent capability previously cost $300-1000+.
Calibration is required for accurate measurements and takes practice. The 4 in touchscreen is adequate but not large. Dynamic range drops above 300 MHz (about 40 dB at 0.9-1.5 GHz). SMA connectors need adapters for most amateur antenna connections (SO-239, BNC). There are many clones of varying quality, so buy from a reputable vendor. 101 scan points limits resolution without a firmware upgrade. The documentation assumes some RF knowledge. It is not a substitute for a professional VNA in critical applications.
An inexpensive vector network analyzer that made antenna measurement affordable for almost any operator. With NanoVNA-Saver on a PC, it replaces far costlier antenna analyzers for most amateur uses.
The NanoVNA is the instrument that made vector network analysis cheap enough for any ham bench. The original is an open-source design by the engineer who goes by edy555; this profile is the NanoVNA-H4, the four-inch-screen version of the popular NanoVNA-H reworked by the developer known as Hugen. Because the hardware is open, there is no single manufacturer - the same design is sold by a handful of reputable makers and by a long tail of cheap clones, which is the first thing to know before you buy.
What it does is genuinely useful. As a one-port instrument it measures what an antenna or coax run looks like to your radio - SWR, impedance, return loss, resonant frequency - plotted live on a Smith chart or as a sweep. As a two-port instrument it measures things passing through: the loss in a length of feedline, the passband and notch of a filter, the response of a duplexer. Not long ago that capability meant a benchtop analyzer costing several hundred to several thousand dollars.
The honest limit is frequency. The H4 sweeps a nominal 10 kHz to 1.5 GHz, but it generates its higher frequencies as harmonics, and accuracy falls off a cliff past about 300 MHz - dynamic range drops from roughly 70 dB down low to about 40 dB up at 1.5 GHz. For HF and VHF antenna work, which is what most operators buy it for, it is excellent; for serious UHF or microwave measurement it is not the right tool, and a fundamental-mode analyzer is worth the extra money.
It also has to be calibrated. You run the included short-open-load-through standards across the exact frequency span you intend to measure, save the result to one of its slots, and redo it if you change the span - skip this and the numbers are meaningless. The screen is a small resistive touchscreen, best driven with the supplied stylus. The real enable is connecting it to a computer running the free, open-source NanoVNA-Saver, which gives a big display, stitches multiple sweeps together for far more resolution than the device's own 101 points, and exports standard Touchstone files for modelling software. Popular community firmware (the DiSlord builds) adds features and speed.
One practical note: the CH0 and CH1 ports are SMA female, so you wire to them with ordinary male-to-male cables and add an SMA-to-SO-239 or SMA-to-BNC adapter to reach most ham antennas. Costing a fraction of a traditional analyzer, it undercut classic handheld analyzers like the analog MFJ-259C on price and shows you far more, while a premium analyzer such as the RigExpert AA-55 ZOOM still offers a slicker interface and easier one-handed field use. Buy a genuine unit from a known seller, learn to calibrate it, and it is the best value on the bench.