This simple logic level tester was found in Radio Electronics from the 90s. The inverters are of the 4009 type and the power comes from the circuit being analyzed.
This circuit detects traffic problems on a miniature railway by triggering an alarm. The circuit was...
When establishing the voltage at the input of this regulator, the output voltage rises smoothly until...
This circuit was found in a Motorola documentation from 1975. Modern equivalent transistors such...