This circuit works as a booster operating with signals from 1 to 30MHz. The gain is between 1 and 20dB. The circuit is from the 1990 edition of Radio Electronics Experimenter magazine.
Found in documentation from the 1970s, this circuit uses an oscillator and a display to warn of...
This circuit simulates a low-level siren and can be supplied with voltages from 5 to 15 V....
The filter shown in the figure, using only an operational amplifier, is characterized by allowing 1...