Re: making a piezo louder

Now there is another way to do this. If you can pick off the logic
signal, you can use it with an external power supply and a transistor
to switch, to drive a separate self-driven piezo beeper. Here's the
circuit:
|
| A o-------o---------o---o-----------o------------.
| | |10K| | |
| 1000pF | .-. | | |
| --- | | | | |
| --- | | | | |
| | '-' |e .-----o-----. |
| | ___ | |< | + | |
| B o--|<---o--|___|--o-|2N3906 | Beeper | |
| 10K b|\ | with | +| 9V
| 1N4001 |c | Control | ---
| o-----oC Pin | -
| | | RadioShack| |
| .-. | 273-68 | |
| 10K| | | - | |
| | | '-----o-----' |
| '-' | |
| | | |
| '-----------o------------'
|
(created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de)

Cheers
Chris



wow Chris .. thats a lot of info .. and really appreciated.

I really doubt that I will be able to find the logic pulse ...
without a schematic .

I would think that I could use the 4khz signal as an input for a
standard transistor amplifier ... pushing more power to another buzzer

another gentleman suggested a small transformer .. this actually
sounds feasible ..

thanks
mike

.

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