An independent, open replacement driver and control program for the mRS miniVNA Tiny vector network analyser, written after the manufacturer stopped supporting the device. Connect, sweep, calibrate, mark and export from a single portable Windows program - no installer and no Python needed.
Site: https://lrizio.github.io/MiniVNATiny/ | Download: see Releases (Windows, unzip and run)
(simulated data)
- Sweeps in reflection (S11) or transmission (S21) mode, 1 MHz to 1.5 GHz, any start/stop/points; Continuous sweep for tuning a device live; sweep-to-sweep averaging and display smoothing.
- Calibration: 3-term Open/Short/Load for reflection and a thru (+ isolation) response calibration for transmission, with interpolation onto a different sweep grid. Save and load calibration files.
- Plots: Smith chart, return loss, SWR, S21 magnitude and phase, selectable and resizable, manual axis scales, amateur-band overlays, optional negative-dB (S11) convention.
- Four markers with a full readout: gamma, return loss, SWR, mismatch loss, Z, Q, Y, S21 dB/phase and group delay.
- TDR: distance-to-fault from a reflection sweep with velocity factor, window selection and a one-click wide-band sweep for short cables.
- Export Touchstone
.s1pand CSV. - Portable: settings, calibration, and window size and position are kept in
settings.jsonnext to the program, so the folder can live on a USB stick. - Optional update check: one small request to GitHub for the latest release; switch it off with the tick box in the top bar.
pip install pyserial numpy matplotlib
python gui_app.py
The command-line scripts (test_sweep.py, save_sweep.py, cal_report.py, ...) use the same driver, minivna_tiny.py; edit the PORT constant in them to match your COM port. The calibration maths (osl_calibration.py, thru_calibration.py), tdr.py and group_delay.py each have a self-check you can run directly.
To build the exe, use PyInstaller with the Python that has the dependencies installed (--onefile --windowed --icon icon.ico gui_app.py, excluding unused heavy packages such as scipy and pandas if they are installed), and keep icon.ico beside the exe. python scripts/make_user_guide.py (needs reportlab) regenerates the User Guide PDF, which also ships in the release zip.
921600 baud 8N1, ASCII commands terminated by CR. The protocol was recovered by decompiling the GPL-licensed vna/J driver with a small classfile parser (reference/classparse.py) and cross-checking it against an independent Python implementation and the real hardware.
Measurements are only as good as your calibration; see DISCLAIMER.md. Licence: MIT.
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