NOR Gate with Operational (CB19837E)

In the figure we have the way to implement a NO OR or NOR gate with an operational amplifier. The number of inputs can be changed.

| Clique na imagem para ampliar |

Decade Counter with Nixie Tube (CB20141E)
This is an old test circuit for integrated TTL counters, feeding a Nixie tube, common at the time....
Two-Transistor Oscillator (CB1387E )
This old oscillator using germanium transistors has a high impedance headphone as inductor to...
Tone Control Preamplifier (CB18561E)
This preamp with several inputs using germanium transistors from the time was found in Japanese...