This is the factory setting (National Semiconductor) of the TDA2006 as an audio amplifier. The circuit works with 24 V and the diodes can be 1N4148.
This light sensor shield, with operational and TTL compatible output or microcontroller was found...
This circuit is from a 1980s Motorola documentation. The circuit can be made with modern...
The number of pulses produced by this circuit depends on the switch pressed. The circuit is from...