Bi-directional intercom system


Posted on May 31, 2012

This is a very small telephone exchange attached only two ordinary Tele phones. Fully bi-directional facility with an intercom system. When a phone is in off hook condition , Exchange will detect it & send ringing pulse to other phone. When it will be picked up , the connection will be established between both phones. This will be taken place vice-versa.


Bi-directional intercom system
Click here to download the full size of the above Circuit.
Bi-directional intercom system - image 1
Click here to download the full size of the above Image.

This is used normal step down transformer (400ma) for generating three type of deference voltages & 100 AC volt for rigging. It doesn?t provided a PCB pattern for the power supply unit. So a Vero board can be used to build the unit. Parts List : 1.Step down transformer ( 230 V to 30 V , 15 V & 100 V ) 2.Two bridged 1 A rectifiers 3.7805 ? 5V regulator 4.7812 ? 12V regulator 5.1000 uf ? 35 V 6.1000 uf ? 16 v 7.150 ma fuse & it?s holders. 8.Necessary Wires & a wire code for AC supply. This circuit is base on PIC16F84A microcontroller. Two slimier SLIC are connected to The controlling unit. It needs to identify following connections on the controlling unit circuit diagram. This is used normal step down transformer (400ma) for generating three type of deference voltages & 100 AC volt for rigging. It doesn?t provided a PCB pattern for the power supply unit. So a Vero board can be used to build the unit. Parts List : 1.Step down transformer ( 230 V to 30 V , 15 V & 100 V ) 2.Two bridged 1 A rectifiers 3.7805 ? 5V regulator 4.7812 ? 12V regulator 5.1000 uf ? 35 V 6.1000 uf ? 16 v 7.150 ma fuse & it?s holders. 8.Necessary Wires & a wire code for AC supply.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Lead-acid-battery-charger
The electronic blood manometer based on MSP430F449 is designed
USB Powered Stereo Computer Speaker
power supply Why is my simple boost converter giving me such a high peak output voltage
TV Transmitter circuit diagram (VHF)
economy radar detector
audio frequency meter
light activated led scr
A Very Useful Timed Beeper Circuit Schematic
Exit Sign With Battery Protection
IR On/Off Switch Using Microcontroller
State Variable Oscillator
15W Valve Modulator Amplifier circuit



Top