Yes, air horns are probably the cheapest way to get high spl sound signals. I didn't mention it because it appeared you wanted to use an amplifier, possibly having it mobile. A mobile air horn is possible too but I didn't think about that. If you really want to pack a punch, get a train or ship horn or get an electro-mechanical horn.
I want to be able to change the frequency and volume easily. Also I'd like to link it to the music being played if possible. If they want the sound to stop, they turn the music down to an acceptable volume and it goes away.
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You can put a damping element in the horn and remove it but I know, you didn't mean that way. If frequency and volume have to be adjusted in a broad range, speakers are the most reasonable way to go.
A loud and relatively cheap horn driver is the Monacor KU-516. It got a screw-on mount so you can chose from a myriad of horns with a wide range of dispersion alternatives. It got a weather proof rating (IP66), you'll get ~132 dB/1m, 4 of these get you ~120dB in 10m distance but depending on the frequency there could be interferences. That's already extremely loud, very likely already much louder than their own speakers, HiFi speakers rarely reach more than 105dB. Are you sure you need 130dB? That's well within the range of pain and even possible hearing damage, likely just short term impairing due to tinnitus with a short exposure but... well, I am not sure about the laws in your country but that's within the range of assault I assume.
If you load each breaker on the switchboard just below their limit, that should overload the distribution to several houses.
It is unclear from what I can find about the end user power distribution in Australia. One image does show one distribution tap per end user. I have a bit of trouble with that as it increases the amount of wire required enormously.
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That depends on the local grid and the power usage of the neighbourhood. Possible but not guaranteed. But if it works, then he'll also be affected by the voltage drop, it can damage electrical devices (rare) and crash computers, routers etc.
There are also other possibilities to make them stop. A lot of cheap amplifiers are susceptible to radio interference and the long speaker cables are great antennas. Get a CB or SW ham radio, 100-300W amplifier and antenna and get 'on air' with AM modulation and some signal or noise. You just need to borrow it, if their stereo is vulnerable to it, they will very quickly stop. Just remember about switching off your stuff first. 😉 😀
Found the right data. In the US the high voltage step down transformers service a few users. In Australia it seems each transformer services a few dozen users. So a single user probably can’t overload the user level voltage distribution transformer.
Next high tech approach is to build a high voltage pulse generator and antenna. Something like that has been offered to local police as a way to stop cars by blowing out their engine control computer.
However if the circuit breaker panel is outside the home I might just look for remote controlled circuit breakers and a visit when they are on vacation.
Noise to noise just strikes me as inefficient. However firecrackers on the morning after...
Next high tech approach is to build a high voltage pulse generator and antenna. Something like that has been offered to local police as a way to stop cars by blowing out their engine control computer.
However if the circuit breaker panel is outside the home I might just look for remote controlled circuit breakers and a visit when they are on vacation.
Noise to noise just strikes me as inefficient. However firecrackers on the morning after...
There is another approach. Give them Christmas, birthday, etc. presents and let them feel like jerks!
But the nastiest version is to plant pretty flowers like opium poppies in their yard!
But the nastiest version is to plant pretty flowers like opium poppies in their yard!
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That's a completely different scenario. The police shoots a kinda barbed harpoon into the car, the impulse has only to travel half a meter (or less) till it hits some circuits or wires. Here we have a distance of 10m, you need voltages closer to the range of a thunderstorm than the voltage of your power grid. And you will hit your (closer) own devices much harder than theirs. There are probably less complicated ways to shoot your own foot. 😛 😀
They will find that quickly. And then they got clear evidence of tampering.
Well, yes, more efficient. But leaves evidence too and I somehow got the distinctive impression the other neighbours would probably not be showing very much appreciation for such methods. 😀😉
The pulse car stopper I am familiar with does not use a harpoon wire. It is directed EM pulse. It is reasonably directional! It does use fairly high voltage to create the pulse. Trigger on the simple version is a spark gap.
The remote control breakers that I use look just like their non remote control version from the outside of the panel.
But we both know the technology is probably beyond most folks here.
Of course in the US so many folks have guns, you would be better off with the diplomatic approach.
The remote control breakers that I use look just like their non remote control version from the outside of the panel.
But we both know the technology is probably beyond most folks here.
Of course in the US so many folks have guns, you would be better off with the diplomatic approach.
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There are directed EM pulse devices with relatively high range but these are very expensive. But it's not the high voltage, it's - like the name already gives away - an electro magnetic pulse. The ranged device works (roughly) in the radar frequency range. That means, it's
a. very dangerous if you don't build it right, you can literally fry yourself, esp. your eyes
b. can be scattered by metal, concrete etc and is generally not ideal for use in a house. The fine line between not doing anything and destroying electronics is very thin. You can kill a pacemaker easily with an EM pulse.
The directed EM pulse is more like a scalpell, the harpoon variant is more like a sledgehammer and designed to kill the electronics with just one pulse but is generally easier to build.
Yes, you are right! If they look the same then it's almost perfect, that's probably the most effective and elegant way to handle this because even an electrician would probably have problems finding the exact cause and - if he suspects it - will probably just think it's a somehow damaged one. The downside is, you can be caught installing it and it's trespassing and probably other things too, don't know very much about the law in north america (USA, Canada even less).
Guns.. Yes, that's an issue too. Especially when trespassing. 🙄
I remember the 'ol CB radio / Police radio interference coming through loud and clear on my college roomate's ordinary stereo back in the late 70's. Perhaps you could infiltrate their audio system with a repeating message, AM modulated on some high power RF carrier?
I know they make easily purchasable CB radio boosters with way more watts out than the FCC allows; perhaps pointing, say, 100W of AM modulated 30MHz RF at the offending speaker would get picked up by the speaker cables, demodulated in their amplifier somehow, rendering a "Please turn it down" message loud 'n clear?
When I was a kid, my father had a 2 tube AM transmitter he let me play with, removed from a Ward's record player. The TV service technician next door once told me "I heard your voice come out of my TV - better watch what you say".
Admittedly, that's the good old days. Unsure if modern "Class D" electronics would fall for a strong, AM modulated RF carrier nearby. Maybe.
Just...Dont take apart a microwave oven and point that at them. Keep the RF frequency low.
I know they make easily purchasable CB radio boosters with way more watts out than the FCC allows; perhaps pointing, say, 100W of AM modulated 30MHz RF at the offending speaker would get picked up by the speaker cables, demodulated in their amplifier somehow, rendering a "Please turn it down" message loud 'n clear?
When I was a kid, my father had a 2 tube AM transmitter he let me play with, removed from a Ward's record player. The TV service technician next door once told me "I heard your voice come out of my TV - better watch what you say".
Admittedly, that's the good old days. Unsure if modern "Class D" electronics would fall for a strong, AM modulated RF carrier nearby. Maybe.
Just...Dont take apart a microwave oven and point that at them. Keep the RF frequency low.
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ICG
Years back I was working on a very similar project. It wasn’t working and I pointed out that there was a metal band around the wood workbench. The lead disagreed and said “if that was the issue then removing the oscilloscope ground leeead!” An arc about 25 cm long started from his hand as he removed the lead! Next day the metal trim was gone and the unit started working. BTW he was not physically injured.
Years back I was working on a very similar project. It wasn’t working and I pointed out that there was a metal band around the wood workbench. The lead disagreed and said “if that was the issue then removing the oscilloscope ground leeead!” An arc about 25 cm long started from his hand as he removed the lead! Next day the metal trim was gone and the unit started working. BTW he was not physically injured.
You don’t even need amplifiers. Use capable subwoofers, *plugged into the wall*. Yes, you can get subs that will take 120 volts RMS. Even more that will take 60. Eight B&C 18’s in series-parallel will sit there and take it indefinitely, making a LOT of noise. Especially if you have horns.
Not effective to annoy neighbors, but this DOES work on dogs that won’t STFU.
1k and 3.5k, alternating, at a 2 or 3 Hz rate. Point and shoot. The barking stops, they go away with tail between legs.
I do definitely like the idea of getting interference across to the speakers. That would do the trick just nicely. I think some of the several speakers they have running might be wireless though. I would like to look into this idea further for sure.
If that is not going to work, then I'm still thinking about a high pitch tone that is ear piercing (without causing permanent damage) that is linked to the music somehow. Similar to training a dog to stop barking in a lot of respects except I think I might be dealing with lower intelligence that a dog so not sure how well it will work. Perhaps a higher frequency like 12kz or something might work better as long is it is loud enough.
Even the cheaper compression drivers still cost a bit if you are going to use a couple. I wouldn't need 130db SPL for an audible frequency, that was just a figure I had read for ultrasonic frequency to have some meaningful impact. I don't feel a lot of love for Piezos for this application and I know that most of you guys do know what you're talking about. I'm just wondering why?
E.g. If taking the approach of using multiple drivers to get a high SPL, these are only $2.90 each
GRS PZ1142 Piezo Bullet Horn Driver Similar to KSN1142A
They are only 60w RMS and 92dB/W/m but wouldn't 4 of them still get to decent SPL at 60W? Wouldn't it just involve using a signal generator amplified to the rated V of the piezo on a dual rail power supply that can deliver the amps?
ICL8038 Signal Generator Medium/Low Signal Frequency 10Hz 450KHz Triangular/Rectangular/Sine Wave Generator Module 12V to 15V|Signal Generators| - AliExpress
(Doesn't have LCD display so might need oscilloscope to know what frequency it is set at other than really annoying I guess).
There is no graph of SPL vs frequency shown for the one linked above and I know that Piezos can often only put out the quoted SPL at specific frequency range. I'd have to check that but just an example. Might be able to increase the frequency to scare away the cats that sh#t in my yard every night once i'm done as they go up to 30kHz.
If that is not going to work, then I'm still thinking about a high pitch tone that is ear piercing (without causing permanent damage) that is linked to the music somehow. Similar to training a dog to stop barking in a lot of respects except I think I might be dealing with lower intelligence that a dog so not sure how well it will work. Perhaps a higher frequency like 12kz or something might work better as long is it is loud enough.
Even the cheaper compression drivers still cost a bit if you are going to use a couple. I wouldn't need 130db SPL for an audible frequency, that was just a figure I had read for ultrasonic frequency to have some meaningful impact. I don't feel a lot of love for Piezos for this application and I know that most of you guys do know what you're talking about. I'm just wondering why?
E.g. If taking the approach of using multiple drivers to get a high SPL, these are only $2.90 each
GRS PZ1142 Piezo Bullet Horn Driver Similar to KSN1142A
They are only 60w RMS and 92dB/W/m but wouldn't 4 of them still get to decent SPL at 60W? Wouldn't it just involve using a signal generator amplified to the rated V of the piezo on a dual rail power supply that can deliver the amps?
ICL8038 Signal Generator Medium/Low Signal Frequency 10Hz 450KHz Triangular/Rectangular/Sine Wave Generator Module 12V to 15V|Signal Generators| - AliExpress
(Doesn't have LCD display so might need oscilloscope to know what frequency it is set at other than really annoying I guess).
There is no graph of SPL vs frequency shown for the one linked above and I know that Piezos can often only put out the quoted SPL at specific frequency range. I'd have to check that but just an example. Might be able to increase the frequency to scare away the cats that sh#t in my yard every night once i'm done as they go up to 30kHz.
I'd be careful putting a single frequency at high power into anything. I think you can create a broadband noise source from a zener diode, or a regular diode that you can get to "avalanche" via reverse bias. That noise goes well into the MHz. Maybe have to high pass it at 5kHz, low pass it at 25k so the amp doesnt blow up. DC power supply, diode, couple of resistors and capacitors. I cant imagine what that would sound like at the SPL levels you want!
>I think some of the several speakers they have running might be wireless though.
I lived in an apt; it was a hot summer day so I has the front sliding glass door open. The guy in the apt below was moving out and had parked his van in front of the window; was playing FM radio in it. It was mildly annoying. I told my roomate "watch this" - I took out a cheap 1 transistor FM transmitter. Jammed his station by overpowering the carrier frequency with one having no modulation. His music apparently stopped, so he changed the station. I changed the transmitter frequency to match. Finally, perplexed, he gave up and shut off his car stereo - while we had a good laugh over being so sneaky. No Permanent Damage Done.
These days, he'd just play from his USB stick and there'd be nothing I could have done.
>I think some of the several speakers they have running might be wireless though.
I lived in an apt; it was a hot summer day so I has the front sliding glass door open. The guy in the apt below was moving out and had parked his van in front of the window; was playing FM radio in it. It was mildly annoying. I told my roomate "watch this" - I took out a cheap 1 transistor FM transmitter. Jammed his station by overpowering the carrier frequency with one having no modulation. His music apparently stopped, so he changed the station. I changed the transmitter frequency to match. Finally, perplexed, he gave up and shut off his car stereo - while we had a good laugh over being so sneaky. No Permanent Damage Done.
These days, he'd just play from his USB stick and there'd be nothing I could have done.
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Well, you got something wrong, they aren't 92dB/1W, they are 92dB/2,83V! But that's not your fault, that's what the dealers and the manufacturers write. The impedance of the piezos are very high because they behave like a capacitor. The power ratings are pure fiction, the usual rating is what a speaker at a certain nominal impedance would take, that's why they are often rated at several different impedances and get a lot higher ratings there, that's "mathematics for sales employees" 😀 The actual impedance is very high and drops kinda like a capacitor, the size of the piezo element and the horn got something to say there too but generally the impedance is roughly about
120-1500 Ohm @ 1000Hz
50-500 Ohm @ 2k
30-250 Ohm @ 5k
and drops to single digits @20-40kHz. The impedance varies with different piezo drivers, it's just a rough range. But it means, they don't behave like conventional drivers power/current dependent but instead mainly voltage dependent. If the maximum voltage of a piezo is 30V, that means they don't take the 112W a 8 Ohm driver but just 4,5W @2k because they got probably ~200 Ohm impedance there. If you take a bunch of the cheap ones, you still got barely power demand, you just need a high supply/rail voltage.
To wire them in parallel can get you still a very high spl with a relatively small amp. But they will interact with the output filters of a class D amp and it might start to oscillate on very high frequencies. To avoid that, just put a resistor of a few ohms in series.
The low power consumption makes such an piezo array very mobile because you don't need a big battery and the piezos and horns weigh almost nothing.
A signal generator can of course be used but I'd prefer an old phone and a SG app because you generate a virtually unlimited number of frequencies at the same time or mix it with noise or switch to a mp3 of your choice. You could even activate it remotely without other hardware, just some apps are needed. I don't know such apps but I've already seen it in action.
Yeah, I've seen similar things happening. High voltage and high frequency radio can be a lot of fun! 😀 😀 😀 😉 But it's easy to forget how dangerous it can get, if you exceed certain limits or get too close. These things happen most of the times at the start of the experiments because things get overlooked easily. And then they strike often if you get too used to them and lower the attention and you get caught because routinely "nothing happened" anyway.
What about these?
5-5/8" x 2-5/8" Piezo Horn Tweeter
They are wide dispersion, but I was thinking about mounting 4 of them vertically next to each other inside a long box - maybe a styrofoam cooler box or something. Looking at the narrow width, this should give a narrow horizontal beam but wide vertical beam? One of the reviews has an SPL vs frequency graph. Peak 103db SPL at about 11500Hz. Could run that tone and play to the strengths of the piezos. I'm putting an order through parts express anyway and seems like good bang for back - total $4!!
5-5/8" x 2-5/8" Piezo Horn Tweeter
They are wide dispersion, but I was thinking about mounting 4 of them vertically next to each other inside a long box - maybe a styrofoam cooler box or something. Looking at the narrow width, this should give a narrow horizontal beam but wide vertical beam? One of the reviews has an SPL vs frequency graph. Peak 103db SPL at about 11500Hz. Could run that tone and play to the strengths of the piezos. I'm putting an order through parts express anyway and seems like good bang for back - total $4!!
You could use a 25khz square wave oscillator an inductor and 1uf cap and drive the tweeter(s) with that. It does not have to be very clean. hide the apparatus as well.
kinda like high power pest controller
kinda like high power pest controller
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