Tuesday, 4 October 2011

Remote Control Circuit Through RF Without Microcontroller

This is a simple type remote control by using RF communication without microcontroller. In this project a remote has been designed for various home appliances like television, fan, lights, etc. It gives lot of comfort to the user since we can operate it by staying at one place. We can control any of the appliances by using this remote within the range of 400 foots. In this project consist of two sections, transmitter (remote) and receiver section. Whenever we are pressing any key in the remote it generates the corresponding RF signals, and these signals are received by the receiver unit. ASK transmitter and receiver is used as transmitter and receiver. HT12E, HT12D encoders and decoders are used in this electronic circuit. The block digram of the whole circuit is given below.   



  


In remote section consist of an encoder (HT 12E) and a ASK transmitter. The encoder generates 8 bit address and 4bit data. We can set the address by using the DIP switch connected in A0 to A7 (pin 1 to 8 ) encoder. If we set an address in the remote section, the same address will be required in the receiver section. So always set same address in transmitter and receiver. Whenever we press any key in the remote the encoder generates corresponding 4bit data and send this data with 8bit address by using ASK transmitter. The transmitting frequency is 433MHz. The transmitter output is up to 8mW at 433.92MHz with a range of approximately 400 foot (open area) outdoors.  Indoors, the range is approximately 200 foot.


TRANSMITTER CIRCUIT       
                                                                                               

At the receiver section ASK receiver is present. The receiver also operates at 433.92MHz, and has a sensitivity of 3uV.  The ASK receiver operates from 4.5 to 5.5 volts-DC, and has both linear and digital outputs. It receives the datas from the transmitter. Then the decoder (HT 12D) decodes the data and it will enable the corresponding output pin (pin 10,11,12,13).



RECEIVER CIRCUIT









For relay connection input the pins going to led to cd4017 and make ground common for both circuit.add 6volt relay to the cd4017 circuit at point A and B.









39 comments:

  1. hi ALOK,
    colud you please tell me whether coverage distance can be improved by increasing Transmitting power or by any other means if possible.?

    I need a simple(as this project) wireless remote to operated over say 500 to 1000 meters. do u had any suggestions?


    thanks for ur ideas in advance....

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  2. @giri hii giri...yes the range of the device can be increased upto 500m by increasing the antenna length and supplying the transmitter 10v and receiver 5v.1000m is not possible with this RF module.It can operate upto 500m only.However ,the range can be increased by using two of such RF pairs in which one will serve as a repeater.
    Thanks for your appreciation...

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  3. @ALOK, thank for ur inputs... may i know the antenna type and length required for 500m.?

    also approx budget for whole circuit?

    ReplyDelete
  4. thanks ALOK for ur inputs....
    Can u tell what antenna and how much length u used for this......... also what type of antenna and how much length is required for 500m range.?

    Do antennae are supplied along with Tx and Rx or separately we had to purchase?

    Finally, we cant use breadboard anyway in real application.... so what type of PCB is to be used?... i mean generic or FR4 kind of thing? please give suggestions if any on this regard...
    thank u

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  5. U are welcome Giri...
    Antenna can be single core wire of approximately 17cm length or PCB trace antenna.
    No,antennas are not provided with the Tx and Rx module.You have to make them.Or you can buy antennas used in fm/am radios from electronics shops which cost about 20 to 30 rs each.
    Pcb can be generic or fr4.I would prefer to use generic cause its cheap and the circuit is easy too.The circuit given above is to control the blinking of leds.For device controlling the leds have to be replaced by an inverter ic 74ls04,counter cd4017,and relays.

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  6. i cant enlarge your transmitter circuit, can you please sent it to me? it is for study purpose. thanks in advance :) aizul_han@yahoo.com

    ReplyDelete
  7. @aizul i hav uploaded the new transmitter circuit...kindly check that...

    ReplyDelete
    Replies
    1. Hi Alok,
      Can you please tell me where did you get the transmitter(A-434) and reciver modules(Rx433ASK)... Do you have schematic for the same or similar module schematic is it posilbe to design this modules since if i use readymade modules the project won't be effective. So can you help please .I'm from Mumbai. you can reply to my email vginside@gmail.com Thanks and regards

      Delete
  8. Hi Alok,
    Can you please tell me where did you get the transmitter(A-434) and reciver modules(Rx433ASK)... Do you have schematic for the same or similar module schematic is it posilbe to design this modules since if i use readymade modules the project won't be effective. So can you help please .I'm from Mumbai. you can reply to my email vginside@gmail.com Thanks and regards!

    ReplyDelete
  9. Hi Vijay,
    434mhz RF module are common in hobby electronics shops.You can find it in any project making shop or electronics market.In delhi,u can found it in lajpat rai market.Ya ,sure you can design your own rf module,but it is a complicate task.It will be better if you buy one.Just take a look at your nearby hobby shops.You can also purchase it online.

    ReplyDelete
  10. Hi Alok,
    will the above circuit work for RXD1 module?

    ReplyDelete
  11. why are we using flipflop in the first circuit?can you please tell me?will the circuit work with out using flipflop also?

    ReplyDelete
  12. Hi,
    Why are we using flipflop in the first circuit?Will the circuit work fine if I directly connect the output of decoder to current driver?

    ReplyDelete
  13. Hi ALOK.
    Can u please send me the circuit diagram of tx433 and rx433 with ASK to vasanthkumar.v@hotmail.com..
    thanks in advance..

    ReplyDelete
    Replies
    1. Hello,
      It will be better for you to buy a tx rx module instead of making one.It will cost you around 200.Anyways,ya sure i will send you its circuit diagram....

      Delete
  14. hi,i just want to know if this transmitter and receiver will work for rc plane?
    can u share some circuit diagram for rc transmitter and R.. plsss...

    ReplyDelete
  15. hello,rc plane needs small weight components,this circuit needs a decoder in reeiver side with receiver module,the assembly will be little heavy...anyways u can try these components but u will have to use high power motors...

    ReplyDelete
  16. hi...i want to make remote controlled home appliances.....can this circuit perform turn on & off both operations...??
    moreover which flip flop is used??
    and is it like to use this circuit on devices, we have to use flip flop....and if we just want to use leds then flip flop is not needed...??
    i m hoping your reply....

    ReplyDelete
    Replies
    1. ya sure...u can use cd4017 IC as toggle switch...refer to its circuit on google...flip flops are actually used to maintain a state...like if we press a button the corresponding device will turn on...but if we release that button the device will get off...there a flip flop satisfy our requirement of maintaining the device on in first press and off the device when button is pressed again...just replace the LEDs with four cd40177 and also a relay driver uln2003 ic....

      Delete
    2. thanx for ur response.....can u plz send me the link for using cd4017?? i m not getting circuit diagram u specified and how this decade counter is used with this project....!!and which flip-flop (d flipflop,jk flip flop, etc.) is to be used....??

      Delete
  17. can u send me detailed circuit diagram along with cd4017,flipflop and relay.....??it would help me more.....

    ReplyDelete
    Replies
    1. I have added the cd4017 circuit diagram for relay connection...check it out...

      Delete
  18. dude, i'm using HM-T and HM-r module,does that module works with above ckt?

    ReplyDelete
    Replies
    1. Hi bibek,ya sure you can definitely use HM-T and HM-R modules but be careful with the pin configuration...

      Delete
  19. hi sir,i wish to design rf controlled device for controlling lights and fans and other small appliances in in a house ...........wat type rf module i need ,,,,and is it possible to control.... pls help me ,i m stuck

    ReplyDelete
    Replies
    1. Use 433mhz rf module...circuit is explained above...

      Delete
  20. Hi i want to add a relay..i have to connect your "converter" to your circuit..i see that your circuit needs 5 volts(the receiver) but your converter needs 9 volts...how it can works with 5 and 9 volts at the same time?or can i put a 5 volt bat instead of 9 volt bar?

    ReplyDelete
    Replies
    1. just connect the circuit input and groung wire with the rf circuit..no need to change power supply of both circuits...only connect ground and input wires....best of luck..

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    2. The ground must be common in both of circuits but the rf needs +5 and the "converter" circuit needs +9?i have to give two voltages?one 9 and one 5 with common ground?

      Delete
  21. hi ..frnd Can i give 9 volt for Transmitter ...
    it's increasing distance

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  22. can we directly connect a motor controller ic "l293d" in place of LEDs in receiver circuit. and how much volts do we get b/w output pins ( d8 - d11 ) and gnd

    ReplyDelete
    Replies
    1. yes you can...the output voltage is aroung 4 volt if driven with 5v...

      Delete
  23. HI SIR, I HAVE SELECTED THIS AS MY MINI PROJECT.BUT I NEED THE DESIGN OF COMPONENTS OF ALL THE ABOVE CIRCUITS.CAN U PLEASE HELP ME OUT WITH THIS??I NEED TO SUBMIT THE DESIGN LATEST BY NEXT WEEK.WAITING FOR UR REPLY.

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  24. This comment has been removed by the author.

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  25. is it necessary to use flip flop if cd4017 connection is used?if yes can u send me the circuit details?

    ReplyDelete