This 8-tube amplifier with 12 W output was found in an American publication from 1947. The output is in counterphase with pentode tubes.
Thes astable was found in old publication of 1968. The circuit uses general purpose germanium...
This low pass filter has attenuation of 5.5 dB and the frequencies depend on the values of the...
This circuit is nothing more than a turn signal for two alternating LEDs that can decorate a robot...