Friday, April 3, 2015

Circuit Schematic Two Way Intercom using LM386 IC

Robometricschool. - Here is simple circuit schematic two way intercom using LM386 IC like in figure 1 below. LM386 is a very popular and widely use 8 pin audio amplifier used to amplify sound signals. The circuit describe below can also be used to amplify the sound signals from mobile output, CD player or it can be used in cars to amplify sound signal.

Circuit Schematic
Figure 1. Circuit Schematic Two Way Intercom using LM386 IC(Source: engineersgarage)


Circuit schematic like in figure 1 above is Circuit Schematic Two Way Intercom using LM386 IC. Working of this intercom circuit is very simple first we have to adjust its gain factor through pin 1 and 8 if it is left open the gain will be 20 as it is internally set in IC but it can be vary by adding a resistor and a capacitor up to 200. Now feed the required signals to pin 2 or 3. A resistor is connected to pin 3 to adjust the sensitivity of input signal and we will get output on pin 5.

C4 is used as current bank for output means when demand for current become low it supplies electrons or when sudden surges of current occur. C5 act as a coupling capacitor remove DC signals and passes only AC signals through it. And we will get the amplified signals through speaker.

The speaker volume can be adjusted with the help of variable resistor VR1.For the circuit to operate as two way intercom make two identical circuits as shown in circuit diagram.  Now connect output of one unit to speaker of other unit and vice versa and use independent power supply for two units and connect them with 3 core wire, two wire for outputs and one wire for common ground is required for intercom connection. You can see from the below circuit how to connect the two units simultaneously. Read more this description using link source below.

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  2. Nice article, Which you have shared here about the two way intercom. Your article is very informative and useful. wireless intercom system is basically used for office or home. Buy wireless intercom online


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