This two-transistor circuit was found in the September 1971 issue of Radio Electronics magazine. The sensor is an NTC and sensitivity adjustment is via R1.
This circuit was obtained in an old Elektor. It is a reference, since the integrated products of the...
The trigger shown in the figure, built around a 4093 can generate pulses that reach 1 hour with a...
This circuit has the transistor chosen according to the maximum current desired at the output. Unlike...