Introduction: Dual NE555 Beeper
Annoy factor: 7/10
This guide is not a follow the lines exactly guide, but a use what parts you have, but there are a few things you need to follow and have
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Step 1: Get Your Parts Together
Gather the parts
Breadboard (Soderless or preforated, either one will work)
NE555 (or any other 555 timer bult the same as the NE555 eg. KA555)
large capacitor of some sort (from 100 uF to 1000 uF)
Small ceramic capacitors (Multiple would be best for better freq range)
Speaker (Im using a peizoelectric which are CHEAP at RadioShack)
Resistors (Currently using a Red Blk Orng, Brn Blk Orng, and orng blk red,)
and a 9V battery (once again any battery type from 4.5 to 14V will work but 9V are easyest to come by
Step 2: Assemble
Assembling, the Schematic is located here and ill put some actual pix up in a while
the primary chips function (set this one up first) is to generate the frequency the beeper will run at. The secondary chip will turn the frequency on and off (beep stop beep stop) so a large capictor will do.
Step 3: TEST AND TROUBLESHOOT
Check all the parts to make shure they are correct and connect power (MAKE SHURE YOU CONNECT THE POLARITY CORRECTLY (+ to + - TO -) IF YOU DONT YOUR CHIPS WILL OVERHEAT AND POSSIBLY BECOME DAMAGED (oh if you are afraid of this just add a diode from + to the power source)) , if no tone is produced adjust the potentometer slowly untill a tone is heard, if a tone is not heard on any potentometer settings a few things could be wrong:
Not enough capcitance on primary = add more capacitors
Wiring incorrect = check wiring and try again
Chip damaged = replace
not correct resitance = change resistance and try again
polarity of battery wrong = install a diode from the positive terminal of your board (or battery) to the positive terminal to your chip( forward biased) and reverse the battery polarity
If you have any trouble other than listed above leave a comment and ill try to get back to you and update the instructable!
picture below is not a picture of the ciruct, but troubleshooting a diffrent one.
Step 4: Deploy :D
Now that you have your beeper working start putting it in random places!
Good hiding spots:
Inside a computer (they will turn it off, unplug it and do all sorts of stuff before they take the cover off)
in a drop down ceiling (LMAO)
in somones drawer under there clothes partially closed
inside a paper shredder or underneath paper shreddings in somones office trash can (i say office cause you dont want someone dumping leftovers on your awesome circut
and if you have any ideas leave a comment, heh this will be fun!