This astable multivibrator was obtained from a Mullard documentation from 1960. The components depend on the used transistor and on the frequency, as shown in the table next to the diagram.
This circuit uses two Raytheon RC4558 operational amplifiers that are similar to the 741. The...
This audio amplifier circuit is from Ibrape's technical documentation from the 70's. The BC177 can be...
This progressive circuit has a lock allowing coded activation. We found this configuration in...