The latest member of our “Top Tenner” beginner’s projects.

As well as its obvious benefit to musicians (aspiring or arrived), this project can be used as a pacer by those busy with aerobics or other on-the-spot exercises. Its display consists of a row of light-emitting diodes (l.e.d.s). These are flashed one at a time, in order from left to right and repeating continuously.

A rotary switch selects the number of l.e.d.s flashed, which is equal to the number of beats in a bar. It allows the user to choose between 2/4, 3/4 and 4/4 time signatures. Another common time signature is 6/8 but, as the fourth note in each bar is often slightly accented, this can be obtained by using the 3/4 setting and doubling the tempo. The Tempo (Rate) is set by a variable resistor (potentiometer) and covers the range from Largo to Presto.

The Simple Metronome also has an audio output. This is provided by a piezo-electric sounder, which emits a short beep at the beginning of each bar, that is, on the count of “one’’, which is when the left-most l.e.d. comes on.