Signals and calibration The source's CONFIG message describes its signals: a name, a unit and a type. udpscope turns each enabled signal into a channel — a ring of values beside the shared time ring — and a channel is what a trace plots. Calibration is a scale and an offset applied at ingest. How to reach it The side panel (s) lists every signal with a switch. The Signal list item in the overflow menu opens the editor where the unit and the calibration live. Worth knowing • Signals start disabled, and enabling one is what starts acquiring it. A trigger on a signal nobody acquires can never fire, so arming a trigger enables its signal for you. • Calibration is applied at ingest, so changing it re-plans the buffer and drops the history. So does enabling or disabling a signal, and so does a new CONFIG. An empty plot for a second after one of those is the ring refilling, not a fault. • The stream's first signal is usually its timestamp, and that one is never acquired. It cannot be plotted, measured or used as a math source, and udpscope refuses to put it in a row rather than binding a trace that would read nothing for ever. • A signal's colour follows the signal, not the slot, so the same signal on two rows is one colour and the side panel's chip identifies it unambiguously. A signal on no row gets a grey chip rather than none, so the panel's rows keep their height. Example A source declaring time, sine, ramp and noise yields three plottable signals. Enable all three and the exit dump reads 3 signals, 3 channels; time is not among them.