Produce ultrasonic audio signals to deter the dog from its continuous yapping - Newbie Needs Help!

Discussion in 'The Projects Forum' started by USNtron75, May 24, 2015.

  1. USNtron75

    Thread Starter New Member

    Dec 14, 2010
    I have a neighbor who's dog barks at all hours of the day. I'm looking to build a device that'll produce ultrasonic audio signals so as to deter the dog from his continuous yapping. Most of what I've seen these devices appear to be driven by a 555 timer circuit. I also noticed that they are powered by VDC. In a perfect world I'd like to be able to power the device with VAC. This is so I can activate the device from inside the house, either through a SPDT (on/off switch) or perhaps a manual trigger. Is it possible to use an ac-to-dc converter in this operation to step down the voltage from 120 VAC to ??? VDC? What else do I know? I know I need a transducer that can transmit (vibrate) at the desired frequency, which I'm assuming a range of somewhere between ~20 kHz and ~40 kHz will suffice. I know I'll need a speaker--or transducer--capable of transmitting such high frequencies. Will I need a signal generator? My intention is to mount the transducer inside a cannon-shaped device like a section of PVC pipe.

    So, if my newbie brain is correct the block diagram would flow as such:

    power source---->signal generator--->amplifier (driver?)--->speaker

    Key Questions:
    1). How do I determine my power requirements? And if I can, is it possible to use an ac-to-dc converter so I can activate the device from inside the home?
    2). What type of signal generator do I need to construct? I suspect one that will produce the desired frequency, correct? Also, once voltage applied will the tone be constant or is there a way to construct the generator so it pulses at certain intervals? Or perhaps, to have both of these options would be valuable.
    3). What type of amplifier do I need to build? I know very little about the fundamentals of how an amp works, but I suspect it needs to modulate the input signal, right?

    Other fundamental concerns:
    1). How do I determine my electrical values on my passive components?
    2). Since I plan on mounting this device on the underside of the patio covering any suggestions for housing the electronics would be great. I think it might be a good idea to incorporate some sort of weather proofing material to avoid any shortages.

    Thank you to everyone on this forum who might be able to assist me with this design.
  2. crutschow


    Mar 14, 2008
    Why not buy one like this which includes a remote and also responds to the sound of the bark.
    I have one and it works fairly well. Usually the dog only barks a few times before stopping after hearing the signal.
    You likely couldn't build one for much less cost.
  3. ranch vermin


    May 20, 2015
    queen trap opening his box again.
    i guess youd have to make sure you supported the hz out of the oscillator through the amplifier.
    I always thought dc tape bias (what you put on an 80's tape player to adgitate the magnetic tape when its 0 volts) would do the same trick, but i guess because its dc its not an audible waveform. (dumbass me)
    Last edited: May 24, 2015
  4. Externet

    AAC Fanatic!

    Nov 29, 2005
    All dog owners are deaf.
    If the ultrasonics project fails, just make a recording of the barking.

    Put your stereo loudspeakers by a window facing the neighbor and play the barking on endless loop at full blast. Then go away for the weekend.
  5. crutschow


    Mar 14, 2008
    So then you can annoy your other neighbors as well as the dog owner. :rolleyes: