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.

Resistive Sensor LED Control II (CB1299E)
This simple circuit controls the brightness of an LED from LDRs, NTCs, PTCs or other resistive sensors....
Sound Roulette (CB16966E)
We found this circuit in a 1990 documentation. It draws one out of 10 numbers and during the draw...
Sawtooth generator (CB23731E)
The circuit shown in figure 3 uses a programmable unijunction transistor (PUT) of the BRY39 type...