Remote Control Circuit Through Radio Frequency Without Microcontroller

Description

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.

Appliance Control Block Diagram
Appliance Control Block Diagram

Remote Section

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.

Remote or Transmitter Circuit
Remote or Transmitter Circuit

Receiver Section

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 date and it will enable the corresponding output pin (pin 10,11,12,13). Each output pins are connected to separate flip flops. The output of encoder will change the state of the flip flop. So its output goes to set (high) from reset (low) state. This change makes a high signal in the output of the flip flop. This output signal is not capable to drive a relay directly. So we are using current driver, SL100 transistor act as the current driver. The appliance is connected to 230V AC through the relay and the appliance will start. The relay will be re-energized when the same switch is pressed in the remote. This is because we are pressing the same switch in the remote control. The output of the decoder again goes to high so this signal will again change the state of the flip flop. So, the relay gets re-energized and the appliance goes to OFF state.

Remote Control Receiver Circuit
Remote Control Receiver Circuit

Components Used

IC HT 12D 1
CD 4017 4
LM 7805 2
TRANSISTOR BC 558 4
SL 100 4
RESISTOR 180 K 4
1 K 4
560 E 4
39K 1
1M 1
CAPACITOR 100nF 4
100MFD/16V 4
LED RED 4
DIP SWITCH 2
PUSH TO ON SWITCH 4
ASK TRANSMITER 433MHZ 1
ASK RECEIVER 433MHZ 1
Author

79 Comments

  1. kandasamy

    i want to control my machine with individual remote by RF method .what will be the cost of remote and receiver unit.approximately 12 nos required.

  2. ASHIK NAIK

    nice.
    But what shall i do to operate some small motor or other equipment momentary.I.E. it should operate while the remote button is kept pressed.Once we release the remote push button the o/p stops.
    Can you please guide me?

  3. Please…
    Give me suggestions
    I made this project…it works well
    But problem is..WHENEVER I POWER ON the circuit….4 channels…on and off immediately.. after few seconds it working well…
    But if I remove the remote battery the circuit relays continuously ON.. Until connect the battery to remote..

    Please say where is problem??

  4. vismaya k.d

    which software is used to simulate this remote control circuit through RF without microcontroller.

  5. Nayan Sharma

    Can we use ULN2003 relay driver chip to drive the relay instead of the flip flop current driver circuit?
    Thanks!

    • Mdmotiur

      Hi Nayan ,yes you can ,but remember 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 date and it will enable the corresponding output pin (pin 10,11,12,13). Each output pins are connected to separate flip flops. The output of encoder will change the state of the flip flop. So its output goes to set (high) from reset (low) state. This change makes a high signal in the output of the flip flop. This output signal is not capable to drive a relay directly. So we are using current driver, SL100 transistor act as the current driver. The appliance is connected to 230V AC through the relay and the appliance will start. The relay will be re-energized when the same switch is pressed in the remote. This is because we are pressing the same switch in the remote control. The output of the decoder again goes to high so this signal will again change the state of the flip flop. So, the relay gets re-energized and the appliance goes to OFF state.

  6. Dear Author,

    I was wondering if I could get a part number for the relay. I’m wondering if I am using the wrong type of relay. When I connect I get a constant buzzing and it is always closed, thus leaving my light bulb on. Please and thank you.

    • Hello…we are doing project on rf remote control…. we have made the circuit as per the figure given above… but the problem is that the relay and led actuates directly when the main power source is on without the use of push to on switch of the transmitter…connection are all right as per the diagram given in the site..except using 12v battery we use 12v rectifier output in the receiver section…..please do reply

  7. susantha

    62 responses to remote control circuit through rf without microcontroller

  8. sutar sarfaraz

    What is the value of c3,c5,c7 and c9 capacitor

  9. if we press two on off butten at a time will it works???

  10. dear sir, there is some confusion for me.
    in the receiver section the ICs (U3, U4, U5 & U6) mentioned as CD40714B.
    but, in the component list it is mentioned as CD4017.
    please guide me, which one is right for this circuit.
    the datasheet of CD4017 differs from CD40714B.

    • do we require any code for dc motor control by using rf wireless communication …???

  11. hey can i use 9 v battery for receiver circuit..,, and also can i use this sme circuit for making rc robot

  12. Hi!. This CD 4017 IC seems to be a decade counter IC. However, CD 4027 is JK Flip Flop. Kindly confirm the use of CD 4017 IC.

  13. Is it okay if i can remove the Flip flop and use the current driver?,connected to relay and then interfacing it with the Appliances.

    What type of relay is the one shown in the above diagram?

    thanks

  14. I want the basic robot making ideas and
    related circuit

  15. i have done this. its working properly. you can use following equivalent components as
    CD4017 = HCF4017
    SL100 = CL100

    • hi prakash, there is some confusion for me.
      in the receiver section the ICs (U3, U4, U5 & U6) mentioned as CD40714B.
      but, in the component list it is mentioned as CD4017.
      please guide me, which one is right for this circuit.
      the datasheet of CD4017 differs from CD40714B.

  16. what does the load connected to relay mean here?

  17. Hi, this site and circuits are very usefull. For remote circuits can i use existing IR remote just like CTV/DVD/AC remote to control various electrical equipments instead of creating another new remote. If it is possible please tell me in detail.

  18. Why wasn’t my previous reply posted? I took good effort in putting the questions together!

  19. Hello,

    I built this circuit, but it doesn’t seem to work. I’ve assembled the components on two separate breadboard one for each side, and since i dont have an oscilloscope, I’ve tried the following diagnostics so far:

    1. Checked and confirmed that all connections and component values are as per he circuit above.
    2. Can confirm that when any dip switch is pressed then then the voltage at pin 17 on the encoder goes high. That seems to indicate that it’s trying to send something to the ASK transmitter.
    3. I dont know of a way to check the transmitter and if indeed its sending something out. I’ve checked that its receiving exactly 5volts as per the rest of the circuit.
    4 on the receiving side, the voltages at pin 18 and the ASK receiver is measured at 5v exactly. The output pins 10 thru 13 show a -0.00 (?) on my multimeter. Pressing the switches don’t change any voltages here.
    5. I have also replaced all components except the ASK components to confirm its not some defective part, but still no luck. I’ve checked youtube and loads of people have had success with this circuit apparently. One guy replaced the 39K resistor with a 51K one to make it work for him. I tried and still hasn’t worked.

    Note: I have not built the relay driving circuit but instead using bc558 transistors to drive an led each for each output to prove the concern works. If it does then I shall put the rest together.

    After 2 days I’ve kind of given up. My final suspicion is on the ASK components which I’ve ordered again. Any suggestion on what else i could investigate would be appreciated. Thanks for reading my post.

    • Hello vijay,
      I had made this and is working fine.
      For step wise testing purpose first remove rf tx and rx from circuit and connect data out pin of ht12e with din pin of ht12d.all 8 address pin should be in same positions in both circuit.u can sort all this 8pins together with ground directly without using dip switch(I have done this).in normal condition when both circuit is powered up the vt pin and all four output on receiver side will show u high.I.e 5 volt.u can attach five 5mm led on this output and vt pin for testing.on pressing any push buttun on tx side the related pin in rx side will go low I.e 0 volt and u will see led at vt pin flicker with every push.

      Thanks

      • Sanjay Sharma

        Dear Sir,

        Can you tell me about how to pairing of the rf and tx.

      • which component u had used as U3, U4, U5 & U6 in the the receiver section.
        pls tell me accurate No.

  20. whith which one can i replace the sl 100 tranzistor??bc547 is correct?this circuit is working properly but the relay which is 6 volt mine dont work…but the led flashes..it is wrong the 6volt relay or the bc547 with replace sl100??

  21. christian dalli

    what is the lowest input voltage and the lowest output the second diagram gives

  22. christian dalli

    hallo
    i just want to know about how big both circuits are?
    thanks

    christian dalli

  23. Tenzin Karma

    De-Energized, not Re-energized…. that was the only part that got me confused, apart from that, all i can say is that this is exactly what i have been looking for for the past 2 days, in vain… and now that i found this circuit, well. i am so happy that i want to give you a chocolate 😀

  24. deepika rawal

    in this project only used ASK why not use the other technique

    • Simple, because it is simple and easily available, low cost and easy to use.

    • Jitendra mattlia

      U can also use IR LED as medium. U have to use 555 ic for genrating 38khz. I build this and working fine for so many years. U can also get circuit using IR remote for 230V ac appliances control. Remote used is a philips tv remote. This required microcontroler. Working fine.

  25. Imam Hasan

    can any one help me how to genarate 8bit data
    in reciver section and tranmitter section
    i made it but not working
    please help me
    give reply to”hasan08eee@gmail.com”

  26. Sheldon Livingston

    Two questions, if I may:

    What are you using for an antenna (small?)?

    A 12 bit encoder = 4,096 combinations. Are aware of a 32 bit encoder?

    Thank you for the info!

  27. its awesome it works perfectly thank u…….. and congrats who built it.

  28. the circuit is looking very complex can i see a simple circuit for the development of this as a project

  29. plz give me full data for tranmitier and reciever……..

  30. Hi,

    Can anyone tell me how to add more security for this circuit more than just the dip switch… I’d like to apply this on our house to automate the parking gate so, I want to make it more secured. And also please indicate other alternatives for the IC’s(HT12E and HT12D) included in the circuit if possible.

    Any help would be much appreciated.. 🙂
    Thanks in advance!

  31. Can somebody hlp me i am frm nigeria the worst country ever i cant even get a 555 timer ic nd i want 2 build an rf remote control circute heeelp!! me pls (umufirdauz67@yahoo.com)

    • Raphael blessing

      Guy u beta, wake up bcs am a nigerian 2, but i av mor dan enough common 555timer chip dat is every electronics shop. Moreover if u tink 9ja is worst goto iraq, mali, egypt etc.

  32. Hi GP Koruthu

    I am too from kerala,
    kollam

    we made this project success.

    Its pretty easy to find all the components in earnakulam

    • Hey,
      I’m trying to implement the circuit for a small exhibition in my college. Could you help me understand the design aspects of the circiut?

  33. Hi Arun,

    As i mentioned in previous comment,

    its easier to make an 8 bit data, just keep an address using Dip switch as same as trnsmtter and recvr

    while switching the 8 bit adress together with data will transmitted

  34. Hi anil,

    Its pretty simple to generate 8 bit data, using this circuit…

    First of all you have to do with,,….

    Use same Dip address for both transmitter and receiver……

    And check for the output…

    If still nothing happenned you have to do is remove the rf module completely (both trnsmtr and rcvr) .
    And connect the Din line of encoder to Dout pin of decoder

  35. hi,
    can any one help me how to genarate 8bit data
    in reciver section and tranmitter section
    i made it but not working
    please help me
    give reply to”anila35@rocketmail.com”

  36. hi,
    can any one help me how to genarate 8bit data
    in reciver section and tranmitter section
    i made it but not working
    please help me

  37. Can you kindly inform that can i get these IC HD12 and the ASK transmitter and receiver in sri lanka and what is price in doller

  38. Jazzy Maistry

    Hi everyone, I Need help. I want to make a disco light that works on 220v power, to work of a remote, please can somebody help me, I found a remote and transmiter but it works on 12V power please help.
    jazzymaistry@gmail.com

  39. avr avinash

    hi friends,
    can any one tell me how to get the ask transmiter and receiver. is there any name of that ask transmiter and receiver like a IC have some name

    • christian dalli

      hallo avr avinash
      you con get them from ebay

  40. G P Koruthu

    Dear M/s Jojo & Vikas Sharma,
    I am not in Delhi. I am in the southern end,Kottayam,in Kerala.Here electronic shops are rare. May be I can find some of these special items in Cochin or so. Any way it’s a hobbey for me after retirement just out of interest.

  41. NILESH SHILANKAR

    it was one of the good mini project,which help me in B.E. 6th semester.
    thanks for the one who design it…

  42. vikas sharma

    hello buddy does anyone can told me that i made this but not working may be my receving part is not working and i dont know why can any one tell me how can i give the vt in the ht12d i give it through 2222 transistor does it wright?

    and mr.g p u will get these ic in lajpat ray market is u are in delhi

  43. how to increase the range of more than 400 foots and also how to increase the MHz frequency. Is any design procedure is for that. pls provide me…

  44. sr..anybody plzz say the circuitdiagram for wii remote whchich is used for video games(tennis) for my project plzz help mee

  45. Hello Koruth,

    I think you can get it near your local electronics store.

  46. G P Koruthu

    Can you kindly inform as to where we can get these IC HD12 and the ASK transmitter and receiver.