Institute Newton C. Braga

Circuit Bench

Internal telephone exchange up to 9 extensions (CB17649E)
Here is a very useful circuit that can be expanded, including the use of more integrated circuits...
MOSFET Electroscope 3N128 (CB852E)
This sensitive electroscope uses a MOSFET 3N128 and can detect electrostatic charges of objects....
4049 Oscillator with Mark and Space (CB24857E)
With mark and space adjustment this circuit was found in November 1984 Radio Electronics. The base...