Hi,
here in Hungary you can get a lot of ready-made IR burglar sensor for
about $20, off-the-self. Why reinvent the wheel?

Regards,
Imre


On Thu, 30 Mar 2000, Mauricio Jancic wrote:

> Hi people,
>         I'm looking for some ideas on how to make a "people detector". The idea is to make a device that plays a pre-recorded voice message (ISD14000 series) each time someone is in front (or near) it.
>         At the first time, I was thinking on a Datalogic infrared sensor (abou U$S 120 + 21% (taxes) here in Argentina). But there were two problems: 1st.  The high price in relation to the rest of the circuit.
>                                                 2nd. As it must be battery powered i make some calc on the total consume and it was too much for me. According to specifications the sensor consumes 25 to 30 mA (the same that the isd when playing) and that get's me to a 2.5 weeks with a 12Ah and 12 v battery.
>
>                                                 3rd. It isn't very nice to put such device on this simple circuit.
>
>         So, wath im looking for is some bright and ease to build ideas on infrared or ultrasound "spectrum".
>         Do you have any??
>
>         Thank in advance, Mauricio.
>
>