NOR gate with the 7400 (CB22406E)

The configuration below shows how to use the 7400 as a NOR function. The circuit is TTL and must be powered with 5V.

Sine to Square Converter (CB6586E)
Found in American documentation this circuit uses transistors of the time. The circuit can be made...
1 W Amplifier (CB6295E)
The TAA300 integrated circuit is not common today. In fact, the circuit shown is from a Dutch...
Rain Alarm or Door Bell (CB5369E)
This circuit was found in a 1980s documentation. Q1 and Q2 can be BC548 and SCR a TIC106. The...