This high impedance step suggested by an English publication can operate up to 1 MHz with 1 V rms output. Input impedance is 1 M ohm.
Found in a 1964 magazine, this is a small headphone amplifier from 500 ohms to 10 k ohms (magnetic...
This is a basic astable circuit using the 555 IC and driving two LEDs. The phase on a rate giving...
The frequency in this circuit is adjusted by P1 and given by C1. Short pulses, as the ones...