Found in a Popular Electronics from the 1990s, this circuit monitors the voltage of a power supply or battery. The trigger voltage is adjusted with a potentiometer.
We found this circuit in the Linear Applications Handbook published by National Semiconductor in...
In the circuit shown in the figure, we add a capacitor (C2) and a resistor (R4) at the base of the...
The range of this transceiver found in an old national publication is of the order of 1 km. The...