Negative Regulator 723 (CB5463E)

The basis of this circuit is the 723, an old integrated circuit not easier to find these days. The power transistor shall be fitted with a heat sink.

Comparator (CB5090E)
The HA2620 integrated circuit used in this comparator is from the 80's, but the setting can be...
Solenoid Current Monitor (CB5399E)
This circuit uses the Linear Technology LT6505 and was found in a 2005 manual. The circuit is for 24 V...
Crystal Radio with filter against Jamming Station (CB934)
This interesting circuit of the American publication Electronics Handbook Volume XIII 1993 shows a...