The TAA300 integrated circuit is not common today. In fact, the circuit shown is from a Dutch Philips documentation from 1969. The output is 8 ohm speaker and 9 V power supply.
This siren circuit was found in 1987. The components are common, and power is provided by standard...
This circuit was found in specialized microwave documentation from the 1960s. The circuit makes use...
Found in Popular Electronics from the 90s, this circuit powers a warning lamp when the load is...