# Trying to design a small game circuit and not sure if I can salvage the buzzers.

#### ganderson

Joined Feb 27, 2019
5
Okay so to start I am at best an extremely amateur project maker. I like to solder and understand somethings about electronics but most of this is way over my head I think. I'm a middle school science teacher and was trying to make a project for my students to assemble a small circuit game where they would have a wire loop that passes around maze and when they touched the maze wire with the loop it would set off a light and a buzzer. I checked with some folks about my circuit and they said it would be fine. I knew nothing about how piezzo buzzers worked. My school approved the purchase and I now have 100 buzzers and I'm not sure how they work.

So the design was a 9V batter connected to a switch and then a buzzer and LED in parallel (The LED is 12v Rated off amazon). The circuit would then go into the maze wire, on the other end of the 9V i would have the loop wire that would complete the circuit when the students touched them together.

I bought these buzzers: https://www.mouser.com/datasheet/2/670/cpe-165-1310296.pdf

and had no idea I need oscillation in my power to make these work so the question I have to those more knowledgeable is there anyway for me to save this, it was a large purchase from my school so I can't ask them to buy more (if it's cheap enough I may be able to take it out of pocket for my mistake) but I'm not sure how to produce oscillation easily with a 9V DC power source.

Thanks for all of your help, I really don't want to tell my principal I wasted the money on the buzzers, and I think the kids would enjoy it more if it lit up and made sound (maybe not the parents)

#### ericgibbs

Joined Jan 29, 2010
15,378
hi g,
Welcome to AAC.
Are you able to purchase a 555 IC device for each buzzer circuit you build.?
What is your location.?
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#### ganderson

Joined Feb 27, 2019
5
I'm in Louisiana, what is the best place to purchase them from? I have yet to find a good store for this locally, so would most likely need to buy online.

#### MrChips

Joined Oct 2, 2009
25,948
Welcome to AAC!

Live and learn. Next time, come to AAC first and have your project checked over before you make any purchases.
How much did you spend so far on the 100 fake "buzzers"?

ak

#### Bernard

Joined Aug 7, 2008
5,788
Same project different name: " Buzz Game- Steady Hand " by Byken, May, 21, 2018. Can be found at top of this page in Search Forums. A $.35 - 555 can drive your speakers with a C & R. Thread Starter #### ganderson Joined Feb 27, 2019 5 Welcome to AAC! Live and learn. Next time, come to AAC first and have your project checked over before you make any purchases. How much did you spend so far on the 100 fake "buzzers"? You can buy 100 buzzers for about$15. That would not be too much of a personal expense to swallow.
Would you have recomendations for something that would drive itself on a 9v?

#### ganderson

Joined Feb 27, 2019
5
hi g,
Welcome to AAC.
Are you able to purchase a 555 IC device for each buzzer circuit you build.?
What is your location.?
E
I was able to find these at a good price on eBay like you suggested. How would it be wired up, do I need any resistors or anything like that before I purchase?

#### ericgibbs

Joined Jan 29, 2010
15,378
hi g,
You do need additional components and PCB strip board for mounting the components and the 555.
I would recommend @MrChips option on using a suitable 9Vdc buzzer, it will be overall cheaper and quicker.
E

#### ganderson

Joined Feb 27, 2019
5
hi g,
You do need additional components and PCB strip board for mounting the components and the 555.
I would recommend @MrChips option on using a suitable 9Vdc buzzer, it will be overall cheaper and quicker.
E
What buzzers should I be looking for? I can't find anything in that price range that seems right.

Tagged him, for you: @MrChips

Last edited by a moderator:

#### MrChips

Joined Oct 2, 2009
25,948
I made this similar game for my kids just for fun.

All I did was connect a buzzer in series with a battery and the wires of the game. You don't need an on/off switch.

Look on ebay for a piezo buzzer that runs on 9V. Do not get a passive buzzer or transducer which is what you have mistakenly bought.
A 5-12V buzzer should also work but there is no guarantee without testing.

Here is just an example. Maybe don't purchase all 100 at once just in case they don't do the job.

#### Bernard

Joined Aug 7, 2008
5,788
Another mounting example using # 8 solid Cu wire.

#### KeepItSimpleStupid

Joined Mar 4, 2014
5,088
here https://www.jameco.com/z/63S109LA-R-9VDC-25mA-400Hz-Mechanical-Buzzer-Wire-Lead_24872.html is a suggestion. It's probably what radio Shack used to sell.

Here's https://www.radioshack.com/products/radioshack-12vdc-mini-electric-buzzer?variant=20332220037 the 12 V version Radio Shack sold. I used it in a "lights on" alarm for the car.

Another part of the design process is selecting a battery and battery life. A 9V battery datasheet is here: http://data.energizer.com/pdfs/522.pdf
I would not go much above 25 mA.

A quick look at Mouser didn't reveal a suitable buzzer. I found one at 100 mA or so.

As the current requirements go down, the cost of the buzzer is likely to go up.

The buzzer requires some sort of mounting and likely PCB leads is not the way to go. You really don't need a power switch. Then there is the battery holder. One example is https://www.sparkfun.com/products/10512 There is https://www.sparkfun.com/products/9518 or similar. The battery connectors can just have leads or can be more robust than you see there. Then there are just clips.
https://www.stewmac.com/Pickups_and...e&utm_medium=shopping&utm_campaign=2019-03-gp

@MrChips it was a gazzilion years ago, I built one. Bells not buzzers back then. I called mine "steady hand" and it was a straight piece of metal and you had to guide a washer down the path.

This https://www.sparkfun.com/products/13939 is way out of line, but it's a really cool buzzer and so is this https://www.sparkfun.com/products/13940 one.

As simple as your design is, you could actually go through the process with the kids. It's basically a 9V battery and a buzzer constrained by costs. What can go wrong?

Take the 9V battery clip. Most are designed to not be used that often (e.g. Smoke detector.) This game, you might like to be a bit more robust, so take a look at this: https://www.digikey.com/products/en?keywords=BS6I-MC-ND BUT the 9V in a self contained holder would liklely be the way to go.

Even I ran into issues with a 9V battery clip. I want the clip to connect to a small connector that can breadboard. Wire guage and insulation thickness show up as well as how easy it is to manually crimp the pins.

The way I approach programming and even one of designs for work is that I start out with the premise:
1) If I had all the money and time in the world available to me what would I like.
2) What do I absolutely have to have.

It turn out, that when programming, I can add hooks which would make adding those features trivial at a later date. If I don't add those hooks, i have to start over.

Returning the parts is an option, but I would buy a few of the parts yourself to test, so you can prove that it works. Asking for a donation would ot be unheard of. All they can say is no. Sometimes educational discounts are available as well.

I'm currently working on a high power LED lamp (6000 lumens) with a Credenza dimmer (cord based). A part of the design is a "locator LED".
I plan to use this https://www.build.com/lutron-tt-300h/s733478 carcass for my control. It has the pot and locator LED. The pot has too large of a value. It's integrated into a switch that is designed to switch 300 W. I want to use that too.

After a lot of mulling, I decided to pigtail a telco cord to a coupler. I will use cross wiring. I went from a 4-20 mA type of syste

Lowest cost is not the objective for me. I'm taking the "industrial control" type of approach.

#### MrChips

Joined Oct 2, 2009
25,948