AC millivoltmeter (CB21862E)

This circuit is from a 1974 Ferranti transistor manual. The circuit is analog, and the components used are period types.

Electronic doorbell (CB25029E)
This circuit was found in the April 1984 issue of Radio Electronics magazine. The integrated...
AC to DC converter (CB14124E)
The presented circuit was found in the National Semiconductor's Linear Applications Handbook from...
Power Oscillator 741 (CB15616E)
This circuit is basically the same as the previous configuration (CB15616E) with a power stage with...