Solar Buzzer Prank

In this instructable I will describe to  you how I made a solar powered prank for April fools day.

The goal of the device was to be at least 50% recycled materials and to cost no more then $5 per unit to make. As a side effect these devices can be mass produced for a larger distribution of the prank or to intensify it in one area.

The simplest idea that I came up with to meet these goals was to use a trashed solar garden light attached to a 3v piezo buzzer. When in the sun the device will produce a rather annoying buzz.

The solar cell from the garden light was removed and the housing and circuitry was retained for future use.

Before buying any additional part I did some research on how much power I  had to work with.

Using my multimeter in voltage mode I recorded an open circuit voltage of 2.8v in moderate light and 3.5v in full light.

Then I switched the multimeter over to current mode and measured the short circuit current to be 50ma in moderate sun and 75ma in bright sun.

Step 1: Purchasing parts

Knowing that my solar cell will output 3.5V at 75mA in bright light and 2.8v at 50mA, I purchased a radioshack part #273-0053 3V Mini Buzzer. ~$3.75

The specifications met the power supplied of the solar cell.
Voltage rating 1.5-3V
Current Consumption 15mA MAX at 3V

These numbers indicate that I could run 3 of the buzzers in parallel simultaneously off of one cell.
1 buzzer consumes 15mA.
The solar cell provides 50mA in moderate sun.
50mA / 15mA = 3 and 1/3 buzzers.

To keep things simple I stuck to one buzzer per unit.

For mounting purposes, I found a piece of scrap wire on the street. You could substitute any sort of wire including coat hanger wire.

Overall the bill of materials include:
1 X Solar Cell salvaged from solar garden light
1 X Piezo Buzzer
1 X Scrap wire

Tools to build this project are
A soldering iron
A glue gun
possibly a multimeter

Comments

[Kiteman]

To turn this idea on its head, you could replace the annoying buzzers with something that plays an actual "note".

Several of them hanging in a small copse, each playing a different note, could be rather pleasant.

And for the intermittent idea, wouldn't a single flashing LED (FLED) do the trick?  If you don't want it seen, wrap it in insulation tape.

[stringstretcher]

Sort of like smoke detectors that need new batteries? :P   I have piezo buzzers that beep in short sequences... could one adapt BEAM technology to turn a solar engine or pummer into a beeping nuisance? I'll bet you can! It would store up energy and then release it at random, like a bird call. Put it into a plastic animal decoy that you have printed... or put it into a barbie doll and tape her to the tree with duct tape (over her mouth?). That ought to win a contest!

[drakesword]

If your gonna store up energy and release it, use an alarm from a security system, loud and startling.

Or servo + stick + pots and pans.

Possibilities possibilities ....

[Mr. Potato Head]

But it wouldn't be very funny if the sound was "rather pleasant". Not really what I would call a prank.

[Kiteman]

That's why I said "turn it on its head" - from prank to artistic installation.

[Mr. Potato Head]

Ohhh, now I get it! Sorry...

[drakesword]

Does a FLED pass current only when it is lit or is it constantly passing current?

I will also look into something that plays a specific note. This is sounding more like urban sound graffiti!

[Kiteman]

Current only when it flashes, I think.

[drakesword]

From some datasheets I saw . . . they pass a specif current when on and a lower current when off.

BTW i saw a box of "twinkling led christmas lights" at BIG LOTS. It was advertised to be "randomly" twinkling which makkes me think that every led was a FLED. 60 lights for $10 so $0.60 per led and you dont have to wait for shipping

[masterochicken]

When I first read your comment I thought it said corpse instead of copse. That would be an interesting prank.

[Kiteman]

...and a slightly disturbing funeral.

[masterochicken]

That would be fantastic.

[drakesword]

I guess it would depend on the funeral lol.

[trailleadr]

Or make it sound like a cicada and do it in January.  Would really blow someone's mind how you would have cicadas in winter.

[incorrigible packrat]

This one time, I heard a cricket on December 26 (and no, I had not been drinking... much)

It was a fairly warm Dec. 26.

The cricket was chirping reeeaalllyyy ssllooooooooowwwwlllyyyyy.

[billythebob]

ive heard u can tell the temp (dont remeber if in *F or *C) by how many chirp per minute/second

[xBRAZZMATAZZx]

i made one it is really annoying

[thepaul1993]

How loud is it?

[drakesword]

It depends on the piezo used but the one I used was audible for a good distance and fairly loud up close

[zizou361]

Hmmm... if I try this, I think another possible placement for the device would be inside a light cover. When someone turns on the light, it starts buzzing, convincing them somethings wrong with the light.

[drakesword]

Thats a good one. I also found that on the outside face of drapes works good too.

[dvcrogers]

What about replacing the buzzer with the guts from an "electronic birthday card"?
If that is possible, you could have a nice tune.

[drakesword]

True but dont know about the power source of these. You may need to devise a cheap way to keep the voltage where it needs  to be without it being too low when its not in bright light.

[incorrigible packrat]

I wouldn't worry about that too much.  Those sorts of circuits only sound more "interesting" when the voltage is off spec. 

[drakesword]

I'll definitely try it when I get one.

[incorrigible packrat]

Cool.   I was just thinking of a talking Alvin (from that cruddy Chipmunks movie) that I found at the dump the other day.  He's just crying out to be hacked for this or a similar project.  The neat thing about it is that at full power he says "hello gorgeous", but if you trigger him enough to run down the battery a bit, he just says "Hell"...

[itsthatsguy]

5 stars, not only for having an original idea, but for using dell, windows FTW!