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 triggers a relay when a pulse of light hits the LDR. The potentiometer serves as a...
In the figure we have the way to implement a NO OR or NOR gate with an operational amplifier. The...
The presented circuit is used to test ordinary fluorescent lamps. This circuit also has a mains...