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 fresh and have a measured voltage of about 6.4 V.

Stripboard

The stripboard size is 9 tracks of 25 holes.