Simple 5V regulator (CB8815E)

This simple 5.6 V regulator circuit was found in a 1966’s Philips. The zener can be changed to obtain other voltages.

Two Phase Motor Driver (CB5419E)
This two-phase stepper motor circuit was found in an old documentation using an operational amplifier...
RIAA Precision Equalizer (CB15964E)
This circuit is suggested by National Semiconductor and with two operational amplifiers an LM833...
Battery Charger (CB24907E)
This circuit is from the September 1985 issue of Radio Electronics magazine. The circuit has an...