The circuit uses IC KT3170 (DTMF-to-BCD converter), 74154 (4-to-16-line demult-iplexer), and five CD4013 (D flip-flop) ICs. The working of the circuit is as follows.
Once a call is established (after hearing ring-back tone), dial 0 in DTMF mode. IC1 decodes this as 1010, which is further demultiplexed by IC2 as output O10 (at pin 11) of IC2 (74154).
The active low output of IC2, after inversion by an inverter gate of IC3 (CD4049), becomes logic 1. This is used to toggle flip-flop-1 (F/F-1) and relay RL1 is energised.
Relay RL1 has two changeover contacts, RL1(a) and RL1(b).
The energised RL1(a) contacts provide a 220-ohm loop across the telephone line while RL1(b) contacts inject a 10kHz tone on the line, which indicates to the caller that appliance mode has been selected.
The 220-ohm loop on telephone line disconnects the ringer from the telephone line in the exchange.
The line is now connected for appliance mode of operation. If digit 0 is not dialed (in DTMF) after establishing the call, the ring continues and the telephone can be used for normal conversation.
After selection of the appliance mode of operation, if digit 1 is dialed, it is decoded by IC1 and its output is 0001.

This BCD code is then demultiplexed by 4-to-16-line demultiplexer IC2 whose corresponding output, after inversion by a CD4049 inverter gate, goes to logic 1 state. This pulse toggles the corresponding flip-flop to alternate state.
The flip-flop output is used to drive a relay (RL2) which can switch on or switch off the appliance connected through its contacts. By dialing other digits in a similar way, other appliances can also be switched on or off.
Once the switching operation is over, the 220-ohm loop resistance and 10kHz tone needs to be removed from the telephone line.

To achieve this, digit 0 (in DTMF mode) is dialed again to toggle flip-flop-1 to de-energise relay RL1, which terminates the loop on line and the 10kHz tone is also disconnected.
The telephone line is thus again set free to receive normal calls.This circuit is to be connected in parallel to the telephone instrument

Download Schematic Diagram Here

Circuit diagram of Infrared sensors and comparators.

Position of sensors,  left hand side is side view and right hand side is top view.

Software

Software for write to AT89C2051 is robot1.hex ,which was written by C-language ,the  source code is robot1.ccompiled by using MC51 in TINY model with my start up code robot.asm .

Figure 1. RF 4 channels remote Transmitter

This is a very simple RF transmitter circuit that consists of the Holtek HT-12E encoder chip and AM 418MHZ-transmitter module (WZ-X01). Using the hybrid RF xmit/receive modules make building the RF remote control a lot easy. ...

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This is a very simple 9V low battery indicator circuit which has 2 LEDs, one green which will light up when the battery voltage is higher than 6.9 volts and one red LED which will light up when the battery voltage is bellow 6.9 volts. You can use BC547 … BC549 .

Under normal conditions (when fuse is alright), voltage drop in first arm is 2V + (2 x 0.7V) = 3.4V, whereas in second arm it is only 2V. So current flows through the second arm, i.e. through the green LED, causing it to glow; whereas the red LED remains off.

When the fuse blows off, the supply to green LED gets blocked, and because only one LED is in the circuit, the red LED glows. In case of power failure, both LEDs remain ‘off’. This circuit can be easily modified to produce a siren in fuse-blown condition (see Fig. 2). An optocoupler is used to trigger the siren. When the fuse blows, red LED glows. Simultaneously it switches ‘on’ the siren.

In place of a bicolour LED, two LEDs of red and green colour can be used. Similarly, only one diode in place of D1 and D2 may be used. Two diodes are used to increase the voltage drop, since the two LEDs may produce different voltage drops.

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