Door Bell

Author admin    Category All projects, Audio     Tags , , , ,


The door bell seems like a simple project but it's not! There is one major difficulty it's to generate a sine wave via Pulse Width Modulation.

The output of OC1A from ATMega8 oscillates at 32 kHz and the pulse width determined value from a sine look up table. A low pass filter of 1.8 kHz removes the 32 kHz. The resulting output is a pure sine wave.  To archive a better sound I used two sine waves at the same note but at a different octave. You can listen this song here. The decay of each note is done via another PWM which control the gain of the output amplifier.


  • Many different songs can be done
  • Nice sound




Source Code

20 Comments to “Door Bell”

  • Custódio Barcellos January 21, 2011 at 10:26 pm

    Hi Sylvain,  I would like to hear the sound of Door Bell but the link is lost..
    Can you help me?
    Thank you,

  • admin January 21, 2011 at 10:31 pm

    I just email you the mp3 file


  • Custódio Barcellos January 21, 2011 at 10:42 pm

    Thank you,  
    nice sound,

  • abdullah June 1, 2011 at 4:06 pm

    Really nice project!
    What are those connectors on the left of the schematic going into PORT D for?

  • admin June 1, 2011 at 4:09 pm

    To select the song to play

  • Rudy Pycke October 11, 2011 at 7:35 pm

    Can you please send me the MP3 file with the sound samples?

  • admin October 11, 2011 at 7:43 pm

    Just right click and save it…

  • Rudy Pycke October 11, 2011 at 9:12 pm

    Right click where?

  • Henry March 26, 2012 at 6:35 pm

    Is it possible to alter the project under WinAVR. thank you

  • admin March 26, 2012 at 6:40 pm

    Yes you can do it

  • Henry March 26, 2012 at 7:36 pm

    redesigned the project can send the mail

  • Sylvain March 26, 2012 at 8:04 pm

    Hi Hi Hi Hi

  • ehsan April 30, 2012 at 1:57 pm

    Hi there

    I'm interested in hearing your bell's voice but i couldn't find it here, please send me the file
    thank you so much

  • admin April 30, 2012 at 2:08 pm

    Please give me your email address

  • richard August 17, 2012 at 11:37 pm

    great projects, just what i was looking for. i have been wanting to combine a bunch of things into one like the intercom, door bell, thermostat (would be fun). i want it for the garage so if someone rings the door bell i will get it over the intercom. thanks for the schematics
    great job

  • admin August 17, 2012 at 11:59 pm

    The sound via the intercomm is already done, but it’s not on blog, when my cloth washer and dryer is finish it’s say in the intercome (in french) the laundry is calling you !!!

  • savage olatunde July 21, 2013 at 2:06 am

    please send me the audio file. and i need your help in a project that i need to record 20 different messages on a mmc card and playback it differently with a push button please i will appreciate it if u can help me and put me through on how to go about it

  • admin July 21, 2013 at 4:24 pm

    I don’t have time for this, I work hard

  • H.Vismeh December 3, 2013 at 9:27 pm

    i am from Iran in Asia
    your projects is so nice
    i download doorbell and megaload , i want use them in my industry project,
    i need PC code of megaload, i will call you .

  • admin December 3, 2013 at 9:28 pm

    The code is available for 100$usd it’s written in visual studio 2008 c#

Post comment

Please note

All my source codes were taken from my personal projects.

Everything is for your information only. The C/C++ codes have been written
with ICCAVR. You can find the header and source CRT files by downloading their compiler.

All is for your information and everything is AS IS without any warranty of any kind. No other files are available and I don't make any modification for any body.



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