Found in a European magazine from the 90s, this circuit emits beeps that are several seconds apart to indicate that a device is on. The transducer is a ceramic or crystal capsule.
This low frequency circuit was found in documentation from the 1980s. The values of R and C...
The 4528 is a dual-retriggerable monostable that needs only the timing network formed by R and C...
This ttransistor test was found in a 1987 documentation. It is a simple oscillator that allows to...