hello and thanks for the information.
my unit weighs approx 12-14g ready to mount. they are using a smaller peizo buzzer in their system. these are cheaper buzzers that require a more complicated driving circuit. if you look up the specs on those type of buzzers you will see that they put out about identical dB of sound at the same voltages. you will notice that they are at a much higher frequency of audio which as we all know doesnt travel as far as lower frequencies do. my device is not incredibly fancy or feature packed but it does the job and does it well. my unit DOES work with PCM and also works with 6v systems unlike the one you use.
thanks for the great info.
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