Cable Locator (CB21303E)

This audio detector circuit can be used for cable identification. We found it in a Popular Electronics from the 90s.

Digital to analog converter (CB20539E)
Indicated for applications with a PC, this circuit was found in an English documentation from...
Current and Voltage Regulator (CB10503E)
I found this circuit in a Popular Electronics from 1992. The circuit shows how we can use two...
Bistable Neon (CB10505E)
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...