Author Options:

How do you make an annoying buzzer? Answered

I want to do a practical joke at work.  I want to use IR LED'S to make a sender and receiver so that when I push my remote it will activate the buzzer, but when I let off of the button, the buzzer will stop.

I am assuming that the sending part would be easy, pretty much a battery, button, and perhaps a resistor (and the LED), but how would I make the receiver so it will set off the buzzer?



I just went to radio shack and got this emitter and detector: http://www.radioshack.com/product/index.jsp?productId=2049723

I also bought this buzzer: http://www.radioshack.com/product/index.jsp?productId=2062394

I did a quick hookup (with electrical tape).  I used a momentary switch from an old computer for the emitter.  I know it was working because I used my video camera to detect it.   When I pointed it at the detector/buzzer nothing happened.  I was using about 2 volts, (buzzer votage is 1.5-3VDC). 

I just went to the site to look up the detector and it says the phototrasistor detector is 20V at 25 mA.   On the package the max is 70 V.  

My question, If I use the following configuration, should it work?  I dont want to try this and blow out  my buzzer before I get an opinion.   Thanks

I cant seem to get the pic to upload here, so I put it on my site:

EDIT: 12/30/09

Well, I bought a breadboard and tried to wire it up.  Not a lot of room on those things.   I used 3 9volt batteries for the receiver.  According to the site, they use from 20 to 70 volts, unless im reading something wrong.  I didnt use any resistors, which I should have.   As soon as I hooked up the power the diode burned up. lol.   Oh well, lesson learned = $1.00.  I'll have to give this  more thought.


to truelly make it anoying skip the diode's and hook a AA battery strait to the buzzer and put it where you walk by a lot.          =)

I was just wondering.......maybe I can modify an old cordless phone that has the find feature on it.  That way I'll be using radio frequency so I wont need a line of sight.  hmmmmmm

Ack!  Don't they even have a schematic with it?  RS has gotten really useless lately.... :-(
The EASIEST solution, given the simplicity of your transmitter unit, would be a simple, shielded IR photo transistor or IR photo diode.  Shielded meaning, putting a hood or tube around it so as to block out most ambient light sources. The photo transistor would be fairly easy, since the transistor is already a "switch" of a sort.