Door buzzer or alarm (CB20492E)

This solar powered circuit was found in a 1991 documentation. The transistor is a general purpose NPN.

1-quadrant logarithmic converter (CB7333E)
This temperature compensated circuit was found in a Popular Electronics from the 90s. Integrated...
MPLAB® Mindi™ Analog Simulator with SPICE and SIMPLIS Environments
MPLAB Mindi Software Updated to Include Over 300 Device Models and Schematics CHANDLER, Ariz.,...
CA3080 Trigger (CB25138E)
Found in a May 1988 Radio Electronics issue, this is a Smitt trigger that requires a symmetrical power...