High power ultrasonic deer alert/repeller mounted on vehicle

Thread Starter

ScottKrieger

Joined Dec 17, 2015
6
Hi All!
New here but fascinated with electronics, but being a busy Dad and now Grandfather, need some help from this experienced crowd.

I drive a fair amount back and forth to work, mainly country roads and LOTS of wooded areas. I have had my encounters with deer, having one graze my car last year and want to minimize that if possible moving forward. I have a Hornet electronic deer alert http://www.xp3hornet.com/ installed and use it with what I think are good results, but I fear it is not aggressive enough and want more...

I have done lots of research and find that reading several studies that increasing my ultrasonic warning presence would be very beneficial.

My plan is to use two high power piezo tweeters http://www.parts-express.com/grs-pz1142-piezo-bullet-horn-driver-similar-to-ksn1142a--292-448 with a high power amplifier http://www.pyleaudio.com/sku/plam2300 and this IC chip http://myskunkworks.net/index.php?route=product/product&product_id=58

The amp is good to 30kHz and the IC chip has an ultrasonic output that sweeps to 25 kHz. The amo is 75 watts RMS per channel and the tweeters rated to 100W RMS.
The chip has four settings, so I am going to install a non-shorting rotary switch to ground between sound outputs to have some fun along the way. I don't want to use this maliciously, but the ultrasonic animal warning output is exactly what I need.

I have read on many sites that an inductor should be used inline with the tweeters for best protection and to convert the wave from square to sine?

Does anyone have a suggestion on what I should use with these components? I am lost on the inductor suggestion????

Thanks all! Lookout for my next project on my boat: Switching between powered amplifier outputs and speaker level outputs when at anchor to save battery power using 4PDT relay trickery
 

Thread Starter

ScottKrieger

Joined Dec 17, 2015
6
Mike thanks, but that is surely not the intent, I drive on a lot of back country roads and have had my fair share of close deer encounters.

The transducers are going to be mounted in PVC pipe which makes them very directional, and will be aimed:: driver side ahead and slightly left, passenger side slightly right. No dogs will be affected unless they are on the right of way at the road. I hope that is not where you keep yours.
So with that being said, if any dogs ended up being on the side of the road, this may actually save them, by spooking them out of the way.

I only use my current ultrasonic device above 40-45 mph, never in the city and I am also looking for a speed sensitive way to turn them on and off. Right now I control it with a lighted toggle switch on the left hand side of the dash, close enough to the steering wheel that I can flick it on or off without removing my hands from the wheel.
It is also powered via relay from the headlights, so the circuit can only be activated when the headlights are on, at night or inclement weather. I might include a photo cell....hmmm....
 
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Papabravo

Joined Feb 24, 2006
12,770
Well you can't get something for nothing so how much of your power output are you willing to lose to a series inductor? Half, two-thirds, or three-fourths?
 

GopherT

Joined Nov 23, 2012
8,012
So with that being said, if any dogs ended up being on the side of the road, this may actually save them, by spooking them out of the way.

..
So, last summer I was helping my son with his rear drum brakes on an old Camry. As he applied the brakes to make a u-turn, my old ears heard a mild squeak, he apparently heard something louder as he raised his head quickly, and the dog getting walked on the shoulder of the road must have been in severe pain - it jumped and did, what I call, a barrel roll. There was nothing else around that would have caused that sudden reaction. The dog's owner, an older woman, lost grip of the leash. We stopped to help her get her dog back. She didn't know what happened, she said she didn't hear anything. When we got back to the house, he took it apart and found that one of the spring-steel clips broke and part of the steel was apparently bound between shoe and drum to make a high pitched squeal.

All that just to say, Bullshit on your "saving the dog" theory. A dog getting walked on the side of the road will not be happy with your device. Also, if it is super directional, and as you said, it will be pointing exactly at a deer for a very short duration - creating a short "beep" and more likely startling the deer in any random direction rather than scare them away from your car. That all assumes that deer CAN hear ultrasonic frequencies.

Then, there is this document from the state of Connecticut, it claims there is no proof that deer can here ultrasonic frequencies.

image.jpg

http://www.ct.gov/caes/lib/caes/documents/publications/fact_sheets/controllingdeer.pdf

If you are hitting deer, you are likely not paying attention or driving too fast, or need to learn how to "really" apply brakes instead of using them to slow down quickly.

Welcome to this website.
 

Papabravo

Joined Feb 24, 2006
12,770
I still don't understand what it will do for me, will it protect the transducer somehow, present an easier load to the amp?
It will change the impedance of the speaker from what is currently is to something else that will be larger. When you change the load by increasing the impedance you reduce the amount of power delivered to the load. If you want a sine wave you should generate one.
 

Thread Starter

ScottKrieger

Joined Dec 17, 2015
6
There have been some good studies done on deer hearing, especially disproving the plastic bumper mounted "whistles" have no effect on deer. There have also been some very detailed studies done, one by the University of Georgia a group of students conducted auditory brainstem tests on deer (in a very humane manner) and concluded this -
"I determined that white-tailed deer hear within the range of frequencies we tested, from 0.25-30 kHz, with best sensitivity between 4-8 kHz. The upper limit of human hearing lies at about 20 kHz, whereas we demonstrated that deer detected frequencies to at least 30 kHz. This difference suggests that research on the use of ultrasonic (frequencies >20 kHz) auditory deterrents is justified as a possible means of reducing deer-human conflicts."
https://getd.libs.uga.edu/pdfs/d-angelo_gino_j_200705_phd.pdf
It won't be "super" directional, it just won't be broadcasting to anything in my path. I do slow down where deer are known to be present, it's just here in NC there are a lot of them and the rut really gets them moving. I have only had a close encounter and one grazed my car, breaking a mirror. Last year on hit my Daughters car and $4,000 in damage. She was doing the speed limit, and it happened like a lightning strike.

Back to the inductor question please....
 

tcmtech

Joined Nov 4, 2013
2,868
As far as I am concerned you can drive by my place with your high powered ultrasonic emitters turned all the way up if it will chase the deer away!;)

I say go for it! It sound like a fun experiment to do and as far as others go no matter what you do someone will always complain about it regardless.

The odds are no one is carrying any portable directional ultrasonic detectors/tracking units while walking around outside any way so it's extremely unlikely that anyone could pinpoint your vehicle as being the source given the very short durations that you would expose them to as you drive by at 45+ MPH.

As far as other peoples domesticated animals go, Meh. Anyone who has ever had pets knows they can and will spaz out for reasons we humans cant comprehend any way. Smells, sounds and sights that are below or beyond our range of detection/concern are everywhere and who knows how an animal is going to react to them at any moment making the likelihood of anyone being able to pinpoint their pets odd behavior to your random vehicle passing by pretty difficult.

I say blast a way at the deer being I know how expensive deer damage to vehicles gets.;)
 

Papabravo

Joined Feb 24, 2006
12,770
Here goes:

[TRIGGER WARNING]
I often use intemperate and sarcastic language when responding to questions without suitable information and detail. Especially offensive are posts with "help" or "urgent" in the title. If you are a sensitive soul you should be advised to find another avocation, or at least another forum for your needs, where people actually care about your particular sensitivities.
[/TRIGGER WARNING]
 

DUFFER

Joined May 3, 2013
11
So, last summer I was helping my son with his rear drum brakes on an old Camry. As he applied the brakes to make a u-turn, my old ears heard a mild squeak, he apparently heard something louder as he raised his head quickly, and the dog getting walked on the shoulder of the road must have been in severe pain - it jumped and did, what I call, a barrel roll. There was nothing else around that would have caused that sudden reaction. The dog's owner, an older woman, lost grip of the leash. We stopped to help her get her dog back. She didn't know what happened, she said she didn't hear anything. When we got back to the house, he took it apart and found that one of the spring-steel clips broke and part of the steel was apparently bound between shoe and drum to make a high pitched squeal.

All that just to say, Bullshit on your "saving the dog" theory. A dog getting walked on the side of the road will not be happy with your device. Also, if it is super directional, and as you said, it will be pointing exactly at a deer for a very short duration - creating a short "beep" and more likely startling the deer in any random direction rather than scare them away from your car. That all assumes that deer CAN hear ultrasonic frequencies.

Then, there is this document from the state of Connecticut, it claims there is no proof that deer can here ultrasonic frequencies.

View attachment 96798

http://www.ct.gov/caes/lib/caes/documents/publications/fact_sheets/controllingdeer.pdf

If you are hitting deer, you are likely not paying attention or driving too fast, or need to learn how to "really" apply brakes instead of using them to slow down quickly.

Welcome to this website.
 
Thread drift, but in our rural neighborhood I've floated the idea of people using paintball guns.
Everyone gets a single color assigned to them.
(If you see a deer with a bunch of yellow on him, that would be me.)
That way we can know who's the best shot!
It could even be a fun contest with prizes.

Steve
 

Lestraveled

Joined May 19, 2014
1,946
A motorcycle rider friend of mine installed an active ultrasonic deer deterrent on his motorcycle. He received a notice from the company that said their initial study was flawed and the device did not work and to please return the device to the company for a full refund. Since he lived across the street, I brought an oscilloscope and a piezoelectric tweeter over and tested the output of the device. It did output about a 30KHz frequency. He said he liked it because it gave him a safe feeling.

Since there is no data that says it really really works, I would prefer to drive a little fearful and be ready for the unexpected.
 

Tonyr1084

Joined Sep 24, 2015
4,037
I usually don't open my mouth (or keyboard) when I don't know the answer. In this case, I don't know the answer. However, I would like to make one simple recommendation to this debate as to what frequencies deer can hear.

Take your standard deer sonic alert and hook it up to a toggle switch. Find a dear - since they're plentiful in your area, park, watch, switch it on and off and see if you get any reaction. Then you can come to your own conclusion about whether deer hear USAF (Ultra Sonic Audio Frequencies) or not.

If you determine they do hear it and react negatively to it then build your boom box USAF.

As for those who feel the need to bark and howl about dogs - and I do care about dogs and other animals - you all might try a more adult approach to express your feelings on it. And I've never noticed dogs reacting to USAF, so - the question: Do dogs really hear in the USAF range? I've seen it on TV. But I've also seen dogs that can fly on TV. (Super Dog for instance, and there was "Underdog" - just to name a few) The point is this: Don't take what someone said on a subject to be absolute. Do your own investigations. Then speak clearly and intelligently about your findings and conclusions. If someone disagrees with you - respect their right to do so. "I'll run you off the road?" Sorry, that doesn't sound adult to me.
 

Lestraveled

Joined May 19, 2014
1,946
@Tonyr1084 , Welcome to the forum. I think you will make a fine member of this band of electronic brothers. On your first post you have reprimanded a member with >5000 posts for his less than subtle humor. Yes, yes, you will make a fine addition.;)
 

Tonyr1084

Joined Sep 24, 2015
4,037
Lestraveled: A wise man will listen and take in more instruction. It goes to reason that a person who opens his mouth more than 5000 times as you said, may not be so wise. And I shouldn't have to be here more than you in order to have a valid opinion.

It's always OK to disagree with me - even call me out for being rude or making a mistake. If nobody is perfect then I must REALLY be a "Nobody". I never take myself that serious. But if you insult someone or make threats - it doesn't matter to me HOW long you've been here.

Yes, I'm fairly new here. And mostly I don't know much about the subjects I've read on. I'm here to learn more than to try and be an instructor. But if my teacher calls me an idiot - I have the right to say "That wasn't nice of you".

I am much more active on other forums, places where I DO speak of things I KNOW. Electronics is not one of my strong points - that's why I read more than I post. Just because I haven't yet risen to the level of +5K answers doesn't mean I know nothing. I know what I know AND I know what I DON'T know. I DO know when someone is being rude. 5K or not.
 
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