The spectrum scanner

The spectrum scanner sweeps a range of frequencies and draws the signal strength as a graph, so you can see at a glance where the activity is. It is a panadapter-style view the radio on its own does not have.

Running a scan

Open the scanner and choose what to sweep: a band or a custom frequency range, the step between points, and the mode and bandwidth to listen in. Start it and the app walks across the range, plotting the strength (and SNR) at each point and repeating in a continuous sweep so the picture stays live.

Reading the chart

The trace is coloured by signal, red for quiet, through yellow, to green for strong, so peaks jump out, and a marker shows where the sweep currently is. A tall green peak is an active frequency worth a listen.

From peak to listening

Click a peak and the app tunes the radio straight to it. That makes the scanner a fast way to find the busy spots on a band and drop onto them, instead of hunting click by click.

Choosing the range and step

A wide range with a coarse step gives a quick overview of a whole band; a narrow range with a fine step zooms in on a few channels in detail. Match the mode and bandwidth to what you expect to find, for example AM with a few kHz of bandwidth on a broadcast band.