This rectangular signal generator was found in an Electronics World of 1966. The transistors are from that time and modern equivalents can be tested.
This two-tone decoder has a bandwidth of 24%. The circuit is from a 1994 Electronics Now. The...
Bike speedometer (CB20497E) This circuit can be powered by a solar cell. The circuit is from a...
This is a typical common collector amplifier step configuration. The transistor can be used...