(please note that this is not an instructable on soldering or electronic components. prior knowledge is assumed)
Step 1: PARTS!
- 20k ohm resistor (red, black, orage)
- 10M ohm resistor (brown, black, blue)
- 10 uF capacitor
- perforated circuit board
- CMOS 555 timer (MUST be cmos / low power consumption to run on a 3v battery!)
- 3v battery (2032) & battery holder
- asst. lengths of wire
- mosfet (i use a VN10KM, others may work)
- piezo buzzer (apply current and get a beep, just the piezo element itself will not work for this)
- soldering iron
- wire cutters
- box cutter or exacto
- knowledge of soldering and electronics :D
Step 2: Nitty-gritty
if you've got a breadboard, lay one out first and make sure it all works!
AGH sorry! Revised schematic 4/4/09 (thanks dad)
Step 3: On perf board and component leads
my project here is 11x9 holes. depending on the size of your components and your layout, your size my vary.
another good idea is to lay out your components before you cut (to know how much you need) as well as after you've cut it. knowing where things go before you start speeds up the process and prevents having to go back.
one last tip: when cutting off excess component leads, you can save them and use them to make connections to the bottom of your board.
Step 4: Final thoughts
hopefully all has gone well and your annoy-a-thing works! this set up i've just layed out should last about a month.
as with all little projects like this, a magnet can be added to the bottom. this will, however, add thickness, so i prefer using double sided sticky tape.
one of the things think-geek's annoy-a-tron has that this one lacks is a different length of time between beeps. this particular "annoy-a-thing" will beep about once a minute (+/- a few seconds depending on battery life).
ALSO: note that you can change the time between beeps by changing the value of the 10M ohm resistor. if i'm not mistaken, i believe a value of 20M ohm will make it 2 minutes, 30M ohm is 3, so on. (you wouldn't want to go too crazy and make it 10 minutes or something, i don't think that would work. but hey, nothing stopping you from trying!)
your comments are appreciated!