Hi guys. today we are going to make a wireless door or calling bell with a range of 300 meters in an open area compared to 50 meters of the commercial door bells that we commonly see in shops.

This project can be used as a doorbell or as a portable wireless calling bell where connecting calling switch with speaker through wires would be difficult.

I am showing the working principle on a breadboard , though you can assemble the connections suitably inside a casing to suit your needs .

Step 1: Collecting the Parts

Integrated Circuits (ICs)

Timer 555 (NE555) x1
HT12E (Encoder IC) x1
HT12D (Decoder IC) x1

Microcontroller

Digispark 16Mhz USB attiny85 OR Arduino NANO

Transistors

2N2222 x1

Modules

434MHZ Transmitter and Receiver

Resistors

1M ohm x1
100k ohm x1
30k ohm x1

Capacitors

0.001uF / 10^4pF (written as 103 on the ceramic capacitor) / 10nF x2
10uF x1

Miscellaneous

Leds x2
9v battery x2
Jumper wires
Single core wires
Alligator wires x2
8 ohm Speaker x1
Tactile push button x1
Breadboards x2

Step 2: Making the Transmitter

Parts required for Transmitter

434MHZ Transmitter
HT12E IC
Tactile Push button
1M ohm resistor
Breadboard
Wires

Procedure

Just follow the step-by-step pictures above after clicking 3 more images under the bottom right image.

The HT12E is an encoding ic which provides an interface between the transmitter module and the circuit. It has 4 data transfer pins which means it can transfer 4 bits of data.

It also has a 8 bit encryption feature which means you can use something like THIS on both the transmitter and receiver and only when both the switch configuration match the data will be accepted by the receiver. Connect one end of the dip switch to pins 1 to 8 of both ICs (HT12E and HT12D) and the other end to ground. Now no transmitter other than the one with the same switch configuration as the receiver can control the receiver.

Step 3: Making the Receiver

!!! FOR A CIRCUIT WITHOUT A MICROCONTROLLER LOOK AT THE LAST STEP !!!

!!! BOTH NOTCHES OF THE IC ARE TOWARDS THE LEFT(RECEIVER MODULE) !!!

Procedure

Just follow the sequence of step-by-step Pictures.

The HT12D is an decoding ic which provides an interface between the Receiver module and the circuit. It has 4 data transfer pins which means it can transfer 4 bits of data.

It also has a 8 bit encryption feature which means you can use something like THIS on both the transmitter and receiver and only when both the switch configuration match the data will be accepted by the receiver. Connect one end of the dip switch to pins 1 to 8 of both ICs (HT12E and HT12D) and the other end to ground. Now no transmitter other than the one with the same switch configuration as the receiver can control the receiver.

Step 4: Uploading the Code

Download the arduino software.
Download the Digispark attiny driver file above if you are going to use the digispark usb attiny microcontroller or you can just skip the installation process (steps 2, step 3 and step 4) of the drivers if you are going to use a nano.
Now click Files>Preferences and then in the text field near the bottom beside the text additional boards manager copy and paste this link. http://digistump.com/package_digistump_index.json
Go to Tools>Boards>Boards Manager and type digistump and click and install the board.
Download the speaker.ino file above and open it.
Now just connect the board and click upload.(the right arrow)

OFFICIAL INSTALL INSTRUCTIONS

Step 5: Finishing Up

Now all you Need to do is connect the Battery. Connect the battery as shown in the pictures to both the transmitter and receiver.

Step 6: Testing

You are done. Now press the button in the transmitter circuit and hear the buzzer beep.

If it is not beeping check the connections for a loose one and then check all the connections according to the pictures or you can just watch my video HERE to follow instructions easier.

You can even range test it.

Mine is :---meters.