- Blog entry posted in 'cat deterrent, buzbuzer quietening cat deterrent,', May 11, 2015.
I have a number of personal alarm buzzers, very loud and high pitched (could be piezo ) no details, no internal components,
I would like to incorporate them into a cat deterrent,
have considered ultrasonic and checked out circuits, (found them a bit heavy, just starting)
I have run them at a lower voltage with some success.
My question is,
could I use a capacitor charged through a resister to create a pulse, to create a growl effect,
am I being simplistic ?
Limited on knowledge equipment and cash.
Barmy
Sinedup, June 12, 2018
These "handbag anti-theft alarms" as I know them by, are usually a modular IC oscillator, meaning the surface -mounted components are encased with a blob of black epoxy, wired to a button-cell and piezo sounder. So modifying the circuit is not possible. Modulating the output with PWM at low frequency [i]may[/i] create a type of growl, but more likely a cicada-like "chirping", as "on" periods will still oscillate at 2KHz or so. Electronics component outlets (eg Radio Shack) often sell "Sound Effects" PCB circuits which come with ROMS having a variety of animal sounds. What about just using the loud piezo-alarm "as-is"? Or would this upset the neighborhood?
