Current indicator (CB22132E)

In this circuit the voltage across the LED is limited by the diodes. The maximum current also depends on the resistor.

Phase inverter (CB22232E)
Used in audio circuits in the excitation of output stages, this circuit provides audio signals with...
Hum Filter (CB10657E)
This circuit was obtained in an English magazine from 1978. We can easily assemble it because all...
Wavemeter (CB15830E)
We found this circuit in an old documentation from the 70s. The text is the original one of the...