Strategic--Dog--Initiative

Hush Puppy!

Design

SDI FAQ

Products

LINKS:


	-------Mouse-Over image to Animate

	*The Enemy*

Learn about dogs, mans best friend. Find out what to feed dogs as well as what dog bowl to use and even how to adopt a dog. Dogs make great pets so get yourself a dog.

One Remedy

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Another Remedy

"Bark Print"^-_-

Avg. Spectrial Distribution

System Design

Complete System Block Diagram

PIEZO Ultrasonic Speaker & Driver Circuit (~ 75W Tweeter)^-_-


Quad Array for 4X Power^-_-

Ra = ~ 20 k, Rb = ~ 10 k, Ct = ~0.002µF See 555 Timing Chart

DS0026 is a dual MOSFET Driver, National Semiconductor (tied in parallel)
L1, is a 1:12 Autoformer Ferrite Pot-core
Power MOSFET IRFZ44
V_cc = 15 Volts Max.
Bypass with Ceramic caps: 0.47µF & Tantalum Caps 25µF
Use Ferrite Beads in V_cc leads
Keep all leads as SHORT as Possible!
Most parts can be found at DigiKey

Due to the number of inquiries, we plan to offer HELP to our many Beleaguered Friends:
COMING SOON!
Specialized parts to be available at this Web Site


Output Autoformer, L1 = 1 mH (Unwind the top layer of wire, solder a tap, then rewind the layer.)	Piezo Horn Tweeter, 75Watts With Thermal Shutdown Protection

COMING in the near future
SDI KITs, & parts to be available at this Web Site

Caution!! Always use Hearing Protection when using/working with this Device. Sound at Ultrasonic frequencies can cause PERMANENT DAMAGE to your Hearing without your knowing it! --Huh? Caution!!

Rational & Description

"If I entered the dog owners' home and disrupted their "quality-of-life" equal to what they allow their dogs' intrusion to do to mine--I would be promptly jailed!"

My SDI device(s) have worked for the most part at reducing the neighbors' dog(s) from annoying the crap out of me; however, there have been instances where it was more trouble than it was worth.

For the actual dog owners, it works much better due to the proximity of the dog to the device: the quicker the response the more effective. As you play with these things it becomes very clear just how slow sound travels.

Three approaches:
1) A method of detecting (reco) the bark, and squeaking back ~ 1/2 second of ultrasound (~20kHz @ > 75 W).

2) The second method is to record (realtime) the actual bark in an analog CCD delay line (~100 msec FIFO) and upon recognition that the sound is a bark, the device plays back--through a loudspeaker--that last recorded 100 msec of bark. It really confuses them; they start shortening the number of their barks, until they often give up. It is funny to watch/hear their initial confusion!

3) The third approach works well on cold winter nights when you can hear every dog in town, and so can your neighbors' dogs! It is continuous white noise played through a loudspeaker, toward the offending dog(s). This seems to "mask" the sounds that trigger the dog's barking. Be careful however, because you could run afoul of your local noise ordinance--especially if your neighboring dog owner is "gunning" for you!

Questions/Answers

* What is the circuit driven with? Is it an amplifier or stand-alone noisemaker? --It is a "stand alone" Powered Oscillator/Driver.

* What type of pot core and winding? --Actually, I used several pot cores stacked, such that the primaries were driven in parallel and the secondaries were connected in series--all phased correctly. This was done as a quick & dirty way of achieving a "step up" and allow for enough power--before core saturation. The specific pot core specs are only important relative to optimum operating frequency: ~10 kHz to ~40 Khz, peaking at ~ 20 kHz. However, this is not critical due to the broadband nature of ferrite transformers. One could use alternate transformer technology: single large ferrite torrid.

* What is the freq range of the circuit (and a dogs ultrasonic hearing range, for that matter)? --I have typically used a frequency above the human range ~ 20 kHz. Dogs seem to respond to almost any frequency up to 30 kHz (and maybe above). My main intent was to not attract the owner's attention, but use enough power & directivity to get the animal's attention!

Some Products we have found:

Hello,

Because we have received numerous inquiries as to whether we could supply a SDI device, this information is presented.

These are Devices that friends have informed us of; however, I don't have firsthand knowledge or experience with these devices.

We are not in touch with the suppliers, and have no monetary involvement.

GOOD LUCK to all of those/us that must be subjected to thoughtless Dog Owners & their ~~pests~~ pets!

Best Regards,
glen