I once made a hand-siren (which was very loud) that used a CD4060 as self-modulated oscillator. PSU were two 9V batteries in series and the full-bridge output-stage was driving a horn-less piezo driver (don't know if this one is still available). Maybe I stumble upon the schematic one day. The generator part can easily be changed for a different frequency. But I wouldn't use a full-bridge and two batteries anymore nowadays since it is easy to "transform" such a small-bandwidth signal by the use of a simple inductor alone because the piezo is representing a lossy capacitor.
Regards
Charles
Edit:
Found the schematic of the modulator on this French website:
http://www.jeunes-science.org/IMG/pdf/schema.pdf
Depending on how fast you want to modulate you take a counter-output of your choice and lowpass filter this output to get a triangular-like signal (R2 & C2). This one is then used to modulate the oscillator via R3. The oscillator as such just needs R4 and C3 as additional components. It is possible to use the oscillator signal itself to drive the "amplifier" followed by the piezo but many take Q4 (which is the highest counter-output that is available on an output pin) like in this example. If you make two of those operating close together I assume that the result could be quite "unbearable".
Regards
Charles
Edit:
Found the schematic of the modulator on this French website:
http://www.jeunes-science.org/IMG/pdf/schema.pdf
Depending on how fast you want to modulate you take a counter-output of your choice and lowpass filter this output to get a triangular-like signal (R2 & C2). This one is then used to modulate the oscillator via R3. The oscillator as such just needs R4 and C3 as additional components. It is possible to use the oscillator signal itself to drive the "amplifier" followed by the piezo but many take Q4 (which is the highest counter-output that is available on an output pin) like in this example. If you make two of those operating close together I assume that the result could be quite "unbearable".
FastEddy said:
[Off topic a little: I have always wanted to record the Hooded Monk Finch ond some other Finch songs ... mostly way above human hearing range, 12K Htz. and up to above 25K Htz. ... digitally, then using some kind of frequency division technic to drop their tunes [play list?] down to a human listenable bandwidth without out losing content, etc. ... anyone every hear about doing anything like this?]
i was listening to the radio a couple of months ago and there's someone who's done something similar
details are vague due to a sive like memory but when you so bird song down enough it sounds like the human voice this person had then taken it to vocal performers to mimic then speed back up so they'd got humans sounding like birds and birds sounding like humans
" ... the Hooded Monk Finch ond some other Finch songs ... mostly way above human hearing range, 12K Htz. and up to above 25K Htz. ... using some kind of frequency division technic... down to a human listenable bandwidth without out losing content, etc ...
" ... i was listening to the radio a couple of months ago and there's someone who's done something similar ... details are vague due to a sive like memory but when you so bird song down enough it sounds like the human voice this person ... "
" ... probably isn`t difficult for some people to do since they already have bird brains. ..."
... LOL
" ... i was listening to the radio a couple of months ago and there's someone who's done something similar ... details are vague due to a sive like memory but when you so bird song down enough it sounds like the human voice this person ... "
" ... probably isn`t difficult for some people to do since they already have bird brains. ..."
... LOL
the new version of schematics...
the oscillator seems me good (simulation with pspice).
I perhaps have to correct the final amplifier... (this version is very
simple but it needs diodes zener and of an enough precise tension)
direct link :
http://img187.imageshack.us/img187/1643/horndogsc9.gif
the oscillator seems me good (simulation with pspice).
I perhaps have to correct the final amplifier... (this version is very
simple but it needs diodes zener and of an enough precise tension)
direct link :
http://img187.imageshack.us/img187/1643/horndogsc9.gif
Attachments
fasterstill said:
I suppose that this depends on tweeter efficiency...
If for 2.35V it has 94dB with 35v it can give 105 dB ???
(I have intention to use a speakers array for obtain more power)
soongsc said:Does the hearing sensitivity of dogs degrade with age? Starting from the high frequencies?
The circuit have also an adjustable frequency trimmer.
New schematics III
This satisfies me more than the old version.
on Pspice it work very good.
http://img75.imageshack.us/img75/6741/horndog2jr9.gif
http://img386.imageshack.us/img386/6555/dogspicexz6.gif
http://img19.imageshack.us/img19/156/dogsimmb9.gif
I also think that it can easily be converted to single supply...
This satisfies me more than the old version.
on Pspice it work very good.
An externally hosted image should be here but it was not working when we last tested it.
http://img75.imageshack.us/img75/6741/horndog2jr9.gif
An externally hosted image should be here but it was not working when we last tested it.
http://img386.imageshack.us/img386/6555/dogspicexz6.gif
An externally hosted image should be here but it was not working when we last tested it.
http://img19.imageshack.us/img19/156/dogsimmb9.gif
I also think that it can easily be converted to single supply...
Gold-XYZ: your device with +/- 35 VDC power will certainly be enough to deafen any dog, gopher or other rodent and probably would generate lawsuits here in the states if the neighborhood kids got in the way ...
It appears that even with an inefficient piezo tweeter, the SPL could be above the threshold of pain.
It appears that even with an inefficient piezo tweeter, the SPL could be above the threshold of pain.
HiFastEddy said:Gold-XYZ: your device with +/- 35 VDC power will certainly be enough to deafen any dog, gopher or other rodent and probably would generate lawsuits here in the states if the neighborhood kids got in the way ...
It appears that even with an inefficient piezo tweeter, the SPL could be above the threshold of pain.
I don't want to deafen anybody..
Also the circuit can be attenuated decreasing the supply
to +/- 12Vcc and limit the sound dispersion with a very directive speakers.
A word from the wise here...hey, not from me - from my mother!
She has a family of ferrets in her attic (3rd genertion or so by now) who always build their nursery in the insulation...so she got herself a commercially avalable unit - fat chance! The wee beastly beasties considered it as detrimental to their living quality and excremented on it, but wouldn't go away.
As to dogs liking that ultrasound jewellery cleaner...mebbe that that thing produces harmonics that mix in nicely and sound very nice to their hearing? If you have cats and tweeters that go high up, buy yourself a whale songs CD from Greenpeace or so - you'll have your home tigers sit in front of the speakers like they are bolted to the floor.
So, producing frequencies we can't hear and judge...imagine all the dogs and children from your 'hood come to your garden and their parents remember that old tale about the Hamlin (Germany) piper (which has a historical background btw)? You might be in trouble.
Pit
She has a family of ferrets in her attic (3rd genertion or so by now) who always build their nursery in the insulation...so she got herself a commercially avalable unit - fat chance! The wee beastly beasties considered it as detrimental to their living quality and excremented on it, but wouldn't go away.
As to dogs liking that ultrasound jewellery cleaner...mebbe that that thing produces harmonics that mix in nicely and sound very nice to their hearing? If you have cats and tweeters that go high up, buy yourself a whale songs CD from Greenpeace or so - you'll have your home tigers sit in front of the speakers like they are bolted to the floor.
So, producing frequencies we can't hear and judge...imagine all the dogs and children from your 'hood come to your garden and their parents remember that old tale about the Hamlin (Germany) piper (which has a historical background btw)? You might be in trouble.
PitWell, ultrasonics might be capable of both - attract and repel depending on signal type and level.
When doing lacquering work on our old dinghy I used a piezo tweeter connected to my signal generator in sweep mode at quite a high frequency range in order to keep our neighbour's cat away.
This animal is very naughty and usually hangs around our house more often than where it actually belongs to. But after my "sonic attack" on it the cat stayed away for days after everything was switched off.
Regards
Charles
When doing lacquering work on our old dinghy I used a piezo tweeter connected to my signal generator in sweep mode at quite a high frequency range in order to keep our neighbour's cat away.
This animal is very naughty and usually hangs around our house more often than where it actually belongs to. But after my "sonic attack" on it the cat stayed away for days after everything was switched off.
Regards
Charles
Charles,
wide range sweep mode might have been a good idea. And btw - Gruesse ins Schoggiland! (all you from not around here will please not mind, that was just an European hi there)...you do a wide sweep, you are likely to get a frequency the beasties don't like.
And don't get me wrong - I'm very fond of having animals around...too fond in fact than having them in an appt. the size of mine, with only concrete all around. The only domestics I allow in, are spiders - they eat every insect I'd rather not have.
Gruetzi,
Pit
wide range sweep mode might have been a good idea. And btw - Gruesse ins Schoggiland! (all you from not around here will please not mind, that was just an European hi there)...you do a wide sweep, you are likely to get a frequency the beasties don't like.
And don't get me wrong - I'm very fond of having animals around...too fond in fact than having them in an appt. the size of mine, with only concrete all around. The only domestics I allow in, are spiders - they eat every insect I'd rather not have.
Gruetzi,
Pit