This circuit was obtained from Linear Technology documentation from the 80's. Powered by 5 V it can be used as a shield. The components are from the era.
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...