Archive for tag: intercom

Door Intercom circuit

Alam Wiring Circuit | By: Diagram mania

Door intercom is very useful for home security. If you receive a door knock or door bell/alarm, you can push this intercom knob and ask the guest  to identify his/her self, before deciding to open the door to welcome. Here is the schematic diagram of the circuit: To install this door intercom, except for right […]

Circuit Diagram for Full-Duplex Intercom using TDA7052 Audio Power Amplifier IC

Audio and Amplifier | By: Diagram mania

The following circuit diagram shows electronics schematic diagram of Full-Duplex Intercom using TDA7052 audio power amplifier IC. The circuit diagram consists of Log. Potentiometer, Resistor, Carbon or Cermet Trimmer, Polyester, Electrolytic Capacitor, Transistor, Audio Power Amplifier, SPST miniature switch, miniature electret microphone, and a 8 Ohm Loudspeaker. This device allows to operate two intercom stations […]

Simple Door Intercom

Audio and Amplifier | By: Diagram mania

This intercom circuit suitable for accompanying  door bell. This circuit uses the speakers both as microphones and as loudspeaker. This intercom is made simple by using only a single amplifier IC LM390 to serve two-way communication. This circuit is based on master controlled half-duplex operation.  With LM390, a 6V battery supply would produce loud enough […]

Intercom

Audio and Amplifier | By: Diagram mania

Below is a 2-station intercom using common 8R mini speakers. The “press-to-talk” switches should have a spring-return so the intercom can never be left ON. Power the speaker from a separate power supply is the secret to preventing instability (motor-boating) with a high gain circuit like this. An extra station (or two extra stations ) […]

Door Intercom

Audio and Amplifier | By: Diagram mania

Door intercom is very useful for home security. If you receive a door knock or door bell/alarm, you can push this intercom knob and ask the guest  to identify his/her self, before deciding to open the door to welcome. Here is the schematic diagram of the circuit: To install this door intercom, except for right […]

Powerline Carrier-Current Remote Control or Intercom

Uncategorized | By: Diagram mania

Using 567 IC tone decoder/detector, we can build a remote control and or intercom. This circuit can be used to control a relay, or to carry an audio signal (intercom) through power-line wiring. Here is the schematic diagram of this remote control/intercom circuit: The relay will be activated if you inject a 100kHz tone. This […]

Two Station Intercom based on LM386

Uncategorized | By: Diagram mania

This a two station intercom. It uses two wires to run between each intercom unit. Each is self contained with its own battery, speaker, microphone and amplifier circuit. An LM386 audio power amplifier is used. It is widely available, used a minimum of external parts and is well suited to battery operation. It will give […]