High Power Alarm (CB20475E)

We found this circuit in a Popular Electronics from the 90's. The circuit uses three SCRs to trigger the loads.

FET stage (CB6169E)
This input stage has unit gain but a high input impedance and low output impedance. The circuit is...
Magnetic Head Preamplifier (CB4945E)
This circuit is from old documentation having a gain of approximately 35 dB at 1 kHz with 2.2 mV...
20 Hz Oscillator with the 555 (CB25512E)
This precision oscillator was found in the October 1992 issue of Radio Electronics magazine. The...