Ultrasonic repellent 4011 (CB9385E)

This circuit was found in Radio Electronics from the 90s. The transducer is a tweeter and the power transistor must have a heatsink.

| Clique na imagem para ampliar |

High-speed optocoupler (CB12759E)
This shield circuit is suggested by Motorola, using a 4N26 type coupler and an MC1733 type...
Oscillator 4001 (CB14985E)
This CMOS oscillator circuit generates signals up to a few megahertz, depending on the capacitor value....
Light-operated relay (CB8285E)
This circuit from Motorola is from 1968, appearing elsewhere on this site. The transistors admit...