Introduction: Sonic Grenade From Mostly Scavenged Parts

Picture of Sonic Grenade From Mostly Scavenged Parts

After seeing a sonic grenade on somewheres on the internet, I wanted to make my own, but living in a small town meant that I would be forced to either order parts and wait for them to come in, or just use what I had on hand. I chose the latter, which ment that I could build it right away, but that it would be somewhat crappier than the one I had seen.

The two things I wanted it to do are
1-Have a pull switch, like a grenade would
2-Provide a small delay between the pulling of the pin and the first noises it made

This is my first instructable, so I welcome any feedback you may have.

Step 1: Get Some Parts Together

Most of the parts that I used came from things that were destined for the trash. The only thing that I ended up buying was the actual noise maker ( thinking that I would not be able to get one, I had originally made my own out of other scavenged bits, but its the noise it made wasn't the greatest). The noise maker is one of those magnetic window alarms. It cost me three dollars for two of them.

You also need a container to put it in, bits of wire, bits of metal, solder, soldering iron, a spring, a tiny push button switch (mine came from a VCR) and other misc garbage type trash.

Step 2: Do Up the Lid

Picture of Do Up the Lid

The easiest thing to start with is the lid. Some holes need to be drilled for this part, and some metal cut.

Out of your misc trash, find something non-conducting and round to use as the pull-pin. (I used a chunk of plastic from the broke VCR, it tapers out a bit making it perfect, won't fall through the hole). Drill an appropriately sized hole in the centre of the lid for it.

On the underside, on either side of the hole, attach pieces of scrap metal. I had originally tried gluing them down, but it didn't work so well, so I drilled holes and used tiny nuts and bolts that I had also scavenged.

Also, I drilled holes for the small reset button, and an optional LED indicator light that tells you when the pin is pulled and the thing is working.

To do the actual pin switch part of the lid will take some trial and error. I used a spring that had a low stiffness and attached it between the metal parts so that it reached across them when the pin was out, and was pressed away when the pin was in.

At this point I soldered wires to all of the things that I had attached to the lid. Be sure to choose an appropriate length of wire.

Step 3: Doing the Delay Circuit Bit

Picture of Doing the Delay Circuit Bit

Easily the most annoying step.

If you have a bread board, I recommend doing up the circuit on that first to test out the length of the delay, and how the alarm sounds when it turns on. The values you end up using for the components will most likely vary depending on what kind of transistors and alarm and all of that you use.

A couple of notes about this circuit -
-Because of the components I had, it isn't very grenade like in the fact that it there is no sound from the buzzer for a few seconds, and then it slowy turns on
-The reset button is there because after pulling the pin the first time and having the buzzer sound, the capacitor needs to be discharged to have the delay the second time. On its own, this takes forever.
-I used regular AA batteries, the alarm came withs its own button cells, totaling to more than 3 volts, but I took them out to use in something else. Do what you please here (as with the whole thing).
-My components are mounted on a piece of a soda pop box, again due to the fact that I didn't want to order any of that circuit board stuff and I didn't have any on hand. The components are attached using the wire wrap techniques with a little bit of soldering at the connections to make sure things didn't shake loose.

Step 4: Attach the Batteries, Alarm, LED, and Switches to the Board.

Picture of Attach the Batteries, Alarm, LED, and Switches to the Board.

Pretty self explanitory here.

For the alarm, I just left it all in the case and put the alarm out to where the batteries used to be in the alarm. At this point, I took some things out of the alarm that it wasn't going to need to be used for this for use in something else (switches).

Make sure the positive and negatives are going to the right places. This shouldn't be hard to figure out.

Step 5: Finish Up

Picture of Finish Up

Test it out a couple of times before putting the lid back on. Be careful when twisting the lid back on, I had some connections come undone on me the first time.

You can also cut out parts of the container to allow the sound out of it better, or attach the pieces a bit better inside so it can be thrown or suchlike. I wasn't to worried about this part as I have been mainly using it to go off when doors are opened.

Kinda of a trivial toy when finished, but I find it entertaining.


Grimling (author)2006-06-11

Very nice , certainly for your first tutorial , Wouldn't it be beter to use a green led ?

ElectricJ (author)Grimling2006-06-11

Using scavaged parts, didn't have a green led.

im making one with a green led, larger cap (470), Tylenol container (looks like a grenade) and a piezo buzzer from radioshack and im spray painting it black :)

alexhalford (author)2007-11-19

you dont really need an led, you know its on when in five seconds it starts making annoying noises

Thundertydus (author)alexhalford2009-02-17

then you know if you accidentally drop the pin =)
also it just generally makes it look way more thoopar hardcore

Notbob (author)alexhalford2008-01-20

An LED can come in handy at night time if you throw it and you don't know where it is. you can just look for the light.

maniac269 (author)2008-04-25

can someone make one that is a sphere and instead of pulling a pin you press a button? plz i am not very good makeing stuff up.

Thundertydus (author)maniac2692009-02-17

definately, instead of attaching that spring and that metal peice attach a toggle switch and solder the leads through that =)

x50rider (author)2008-10-02

were did you get the window buzzer

ElectricJ (author)x50rider2008-10-02

It was quite a while ago now, but I believe that it was either at a local dollar store, or a Canadian Tire.

spork969 (author)2008-09-19

Prove it.

defiant1 (author)2008-08-20

Let's see'em bud.

lamer95 (author)2008-08-01

@#@% you

lamer95 (author)2008-08-01

i like pie

T-K (author)2008-07-27

Dude, the container is clear and wwwwwaaaaaaayyyyyyyyyyyyy too big. Get like one of those new gum containers or some thing.

brian250 (author)2008-07-22

pbkid1 i am unable to find your 1000 times better !!!!!!!!!!!!!!!!! please direct me into the right direction so i can go directly to your better unit.i will get back to you directly when i see the schematics.

kibbler (author)2008-02-13

then let's see u work ur butt off then have some jerk (namely you) put you down!

Mr. Deeds (author)2008-02-08

You know what, you suck!!!!!!!!!!!!!!!!!!!!!!!!! And you use way too many many exclamation points!!!!!!!!!!!!!!!!!!!! Instead of bringing people down, why don't you give advice for a change!!!!!!!!!!!!!!!!!!!!!!!

struckbyanarrow (author)2008-01-27

heres what you do, get a tenis ball and drill a hole big enought to fit a peice of 1/2 in id of pvc it should stick out of the tenis ball about an inch and put what electricj made in side and paint black. wala!

ry25920 (author)2008-01-23

Dude, come on. Least you could do is constructive critcizm.

FunkNattidelic (author)2007-12-27

i bought one of those alarms a little while ago (it said "Similar to those seen on tv" on the package) and after seeing this i thought, 'Why not just push the switch on the actual alarm and throw it?' and also I LOVE TRASH!!! it can be so amusing... I like the concept though...

ElectricJ (author)2007-11-22

u r teh lame

themasterpyro (author)2007-09-06

gonna post overpressure ordnance sometime soon.great for indoors

DavidRobertson (author)2007-05-14

cool . might try to make a better wersion and if i do i will post it on instructibles

pinski1 (author)2006-06-12

Nice idea, but with such a small case, and siren, wouln't it be even better to use a MUCH smaller case ? That and the fact the circuitry is unessesary, although it is still neat. Just replace the slider switch with a PTM and you'll be alright. or even use a magnet as the pin be cuase you still have a reed switch and you'll get a magnet with the alarm. Just some ideas for streamlining the project and simplifying it.

ElectricJ (author)pinski12006-06-12

I was going to mount the innards in a smaller container once I use something up and have one empty. What does PTM stand for? I've not seen this abbrv before and nothing that looked right came up when I googled it. The circuitry is there to provide the time delay between the pulling of the pin and the beginning of the noise. This is the only way I could think to produce this effect(remember I was using what I had handy). I considered using the magnet and reed switch as the pin switch, but the switch is normally closed when the magnet is near, and I wanted to add things without doing to many things to the actual PCB. The reed switch and magnet have already been removed and repurposed in another project. > PTM > whatevertheabbrvwebsiteisthat heylink

Whaleman (author)2007-04-03

u culd convert a smoke alarm into sumthin like this

LoneRanger (author)2007-01-25

I love this! Please post a video tho!

peterrus (author)2006-11-24

Brute :D I think i am gonna build some, they are a cheap distraction method which can cause quite some havoc, i am gonna spray them black and make them look really bad ass. You inspired me :)

electronicfreak22 (author)2006-10-15

the pin and the spring is a really cool setup i never thought of that

Edge (author)2006-10-10

very nice, wasting nothing in the process too!

Camster911 (author)2006-08-31

My mother is a nurse, once she was working on a ward in a rather dangerous area in winter, she got given some kind of alarm, if she got attacked she pressed this button on it, it was very small and a fucking bitch. It was so loud it hurt, and the high pitched sound was awful, i was only young at the time but i wish i had one now...Put it through annoying nieghbors letterboxes.

Odziz (author)2006-06-12

Very neat, I love plowsharing. Any chance of having a go at the sonic rifle from Minority Report next?

ElectricJ (author)Odziz2006-06-12

hmm, guess I gotta watch the movie again.

padfoot447 (author)2006-06-12

Very Nice. I would suggest a plastic case (if that is glass.... I cant tell) because if everything is fixed in place you could throw it around before it goes off... cool!

ElectricJ (author)padfoot4472006-06-12

Its a plastic bird food container. waste not and such

About This Instructable




Bio: Electrical Engineering Student
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