This receiver, whose tuning range depends on L1 and L2, was found in the 1992 special edition of Radio Electronics Experimenter. The circuit is relatively simple and has good sensitivity.
We can use this circuit to connect low impedance microphones and even small speakers used as a...
This alarm circuit is from a 1987 publication, however the components used are still modern. The...
In the figure we have the way to implement a comparator for voltages of opposite polarities. The...