We found this circuit in an American publication from the 90s. It generates pulses that can be modulated in amplitude. The supply can be done by voltages from 5 to 12 V and the frequency depends on C1 and C2.
Found in an Electronic Design from 1965, this circuit makes use of transistors of the time. The...
Found in an EDN from the 90s, this circuit uses an electret microphone. The output can be used to...
This circuit compares the input voltages by providing an output according to the curve next to the...