This circuit was found in a Popular Electronics from the 90's. The CMOS integrated circuit used is not very common nowadays. The range depends on the infrared LEDs. R7 can be changed.
In the figure we have the diagram of an amplifier stage using transistor and a 6AQ5 valve. The...
Being able to operate with frequencies up to 100 kHz, this circuit was found in a 90’s...
This circuit immobilizes a car with an old ignition system with platinum switches. It was found in the...