This 2-tube amplifier was found in a Japanese publication of 1964. The circuit has excellent sound quality. The power supply is not given and must provide a voltage of 300 V.
This circuit uses a common multimeter on the voltage scale to measure the beta gain of a...
This simple optical alarm circuit was found in the 1991 Electronics Experimenter Handbook. The...
This circuit uses an audio output transformer found in old transistor radios. Power output is...