Tone

Summary The circuit drives a speaker to generate a tone. The frequency of the tone can be varied by adjusting a trimmer. Circuit Schematic Stripboard The stripboard size is 9 tracks of 25 holes.

Clock

Summary The circuit switches between lighting one of two light emitting diodes (LED). The frequency of the switching can be varied by adjusting a trimmer. Circuit Schematic The circuit was originally intended to be powered by four AA batteries, each with a nominal voltage of 1.5 V (6 V in total). The batteries are relatively […]

SR latch

Summary The circuit is a SR (set-reset) latch. The input is by means of a two tactile switches (set and reset). The output is displayed using two LEDs (red and yellow for Q and not Q). Circuit Originally, the power connector was a two-position screw terminal (as in the images above). This was replaced with […]