Institute Newton C. Braga

Circuit Bench

Rumble Filter LM387 (CB13490E)
We found this traditional low-frequency filter setting for turntables in the 1977 National...
Overtone FET Oscillator (CB13085E)
The oscillator in the figure has its frequency determined by the crystal. The indicated value is...
Pulse width discriminator (CB9690E)
This circuit was obtained in a 70s American documentation. The integrated circuits of the time are...