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.
Like the previous circuit, this is used in the analog part of the telephone lines. The same...
This analog TV circuit generates bars in the NTSC standard. We found it in the July 1991 issue of...
This transmitter kicks in when the microphone picks up sound. This sound then modulates the signal...