Remote Control Circuit Through RF Without Microcontroller

Remote Control Circuit Through Radio Frequency 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.

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
SL 100 4
1 K 4
560 E 4
39K 1
1M 1
100MFD/16V 4
Show Comments

69 thoughts on “Remote Control Circuit Through RF Without Microcontroller

  1. Nayan Sharma

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

  2. Jeff

    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.

  3. fahad

    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.

  4. Rohit

    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.

  5. Macheda

    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?


  6. Prakash

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

    • fahad

      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.

  7. NITIN

    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.

  8. Vijay


    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.

    • avijeet

      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.


  9. panos

    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 is wrong the 6volt relay or the bc547 with replace sl100??

  10. 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 😀

    • 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.

  11. 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””

  12. 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!

  13. Louie


    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!

  14. Yassar

    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 (

    • 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.

  15. Tittu

    Hi GP Koruthu

    I am too from kerala,

    we made this project success.

    Its pretty easy to find all the components in earnakulam

    • Vinita

      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?

  16. Tittu

    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

  17. Tittu

    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

  18. anil

    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””

  19. pradeep

    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

  20. 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.

  21. 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

  22. 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.

  23. 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

  24. R KANNAN

    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…

  25. infant

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


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