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Tools

Library → Tools opens instruments and calculators that are not part of a receiver.

ToolDoes
Antenna calculatorDimensions for dipoles, folded and inverted-V dipoles, end-fed half-waves, ground planes, 5/8 verticals, J-poles, quad loops, and Yagis, with simulated SWR, gain, and radiation pattern
NanoVNASweeps an antenna over USB and shows SWR, impedance, a Smith chart, and cable faults. Keeps sweeps per antenna to compare.
Radio programmerReads, merges, and writes codeplugs, and copies them between radios

Antenna calculator

Pick a design and a band or frequency. Every design is also simulated: the wires are solved with the method of moments, over the ground you pick.

  • Design: the cut list and a drawing. Current shades each wire by how much current it carries. Hover a part to find it in the drawing.
  • Trim finds the element factor where the feedpoint is resonant.
  • Performance: SWR, return loss and impedance over the band, a Smith chart, and the azimuth and elevation patterns. Matching compares baluns, ununs, a quarter-wave line, and L networks; pick one to see its SWR. The dashed trace is the bare feedpoint.
  • Resonances: a sweep from 0.4 to 3.2 times the frequency. ▼ marks a series resonance, ▽ a parallel one. Bands shows which amateur bands the antenna also works on.
  • Save to NanoVNA keeps the simulated curve in the NanoVNA antenna library, to overlay on a real sweep. Export writes a NEC model for 4nec2 or EZNEC, or a Touchstone .s1p.

The model ignores nearby metal, trees, and the feedline. Cut 2 to 5% long and trim on site.

NanoVNA

Pick a band or type a range, then Sweep. Live sweeps again as soon as each sweep ends, for trimming an antenna while you watch.

  • Chart: SWR, return loss, impedance, phase, S21, group delay, and distance. Amateur bands of your region are shaded. Drag across the chart to zoom.
  • Markers: the lowest SWR is marked on its own. Click the chart for up to four more; arrow keys move the selected one.
  • Bands: best and worst SWR in each amateur band the sweep covers.
  • Match to 50 Ω: L networks that match the selected marker.
  • Distance: reflections along a cable. Set the velocity factor of the cable. Low-pass grid moves the start so the impedance step can be shown too.
  • Antennas: name an antenna, then Save sweeps to it. Show a saved sweep as the main trace, or overlay up to four. Open .s1p or .s2p loads files from other tools.
  • Export: Touchstone .s1p, .s2p, or a CSV table.

Calibrate walks through open, short, load, and the optional isolation and thru steps over the current range, and saves the result in a slot on the device. Device sets IF bandwidth and drive.

Radio programmer

Supported radios: AnyTone AT-D890UV and Radtel RT-4D.

It handles what both radios share: channels, zones, contacts, group lists, scan lists, and radio IDs. Write to radio reads the radio first and writes back only the blocks that differ, so the rest of the codeplug stays as it was.

Copy for that radio fits a codeplug to the model picked under Copy to and stores it as a new one. Merge in takes entries from another stored codeplug.

The NanoVNA and the radio programmer need the device plugged into the server, not the client.