This circuit generates pulses from 0.5 Hz to 500 kHz, adjusted by potentiometer P2. The transistor can be the BC547 and the supply voltage must be 5 V. The circuit is from 70's documentation.

This circuit generates pulses from 0.5 Hz to 500 kHz, adjusted by potentiometer P2. The transistor can be the BC547 and the supply voltage must be 5 V. The circuit is from 70's documentation.