Every character is made of two kinds of stroke: straight lines, and arcs traced by putting a sine on the X deflection and a cosine on Y. Stretch one axis and the circle becomes an ellipse; start and stop partway round and you get the bowls of a 2, 3, 5 or S. That's how scope clocks draw such smooth numerals with so little hardware. Press Font sheet to see the whole character set.

Show retrace lights up the jumps the beam makes between strokes, which a real clock blanks out. Hum adds the faint 60 Hz wobble of an old power supply.

Inspired by the NixieBunny scope clock. Companions: the Tek 4006 cobweb plot and the Lorenz attractor on the IRIS.