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.

50 ohm Line Driver LM3900 (CB5056E)
The gain of this amplifier is 10 times and the excursion to the output voltage is 6.0 V (peak to...
Overcurrent oscillator (CB9627E)
The frequency of this circuit depends on the crystal. The transistor supports a modern equivalent. We...
Switching Power Supply (CB25379E)
This circuit uses the SQ3524, a switching integrated circuit. The circuit was found in the April...