This is a 2-station simple intercom circuit build based on transistors part and using common 8R mini speakers. The speaker works as microphone and generate sound, so there is no need microphone for this intercom. The "press-to-talk"…
This circuit was designed to detect when a call is incoming in a cellular phone (even when the calling tone of the device is switched-off) by means of a flashing LED. The device must be placed a few centimeters from the cellular phone, so it…
This is a simple home telephone ringtone generator circuit which is built with applying only several electronic components / parts. It generates simulated telephone ringtone and requires only DC supply with 4.5V DC to 12V DC voltage. One may pos…