Fast adder 1 (CB7055E)

We found this circuit in an Electronic Engineering from the 90s. It applies to any logical family.

Adapter for transistor test using a multimeter (CB3925E)
We found this adapter in a 1970s American documentation on instrumentation. It is suitable for analog...
Gain 10 Amplifier (CB25636E)
Using a general-purpose transistor this AC amplifier was found in the November 1993 issue of...
Headphone Amplifier (CB4269E)
This hearing aid or stethoscope headset amplifier was found in a 1980s documentation. The...