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Archive for the ‘buzzer’ Category

Planning a game of Hacker Jeopardy at your next meetup? You’re going to want some proper buzzers to complete the experience, but why buy when you can build? [Flute Systems] has released an open source DIY game buzzer system based on the Arduino that will help instantly elevate your game. Certainly beats just yelling across the room.

The design has been made to be as easily replicable as possible: as long as you’ve got access to a 3D printer to run off the enclosures for the buzzers and base station, you’ll be able to follow along no problem. The rest of the project consists of modular components put together with jumper wires and scraps of perfboard. Granted it might not be the most elegant solution, but there’s something to be said for projects that beginners and old salts alike can complete.

Each buzzer consists of an Arduino Pro Mini 3.3 V, a nRF24L01, and of course a big pushbutton on the top. Each one is powered by a 110 mAh 3.7 V LiPo battery, though [Flute Systems] notes that the current version of the buzzer can’t actually recharge it. You’ll need to pull the pack out and charge it manually once and awhile. Thankfully, the printed enclosure features a very clever twist-lock mechanism which makes it easy to open anytime you need to poke at the internals.

The base station uses the 5 V version of the Pro Mini, with a Adafruit PowerBoost 1000C to step up the voltage from its 2,000 mAh battery. Of course it also has a nRF24L01, and also adds a buzzer and twin four digit seven-segment LED displays. [Flute Systems] says you can expect about five hours of runtime for the base station.

An especially nice feature of this setup is that the eight digit display allows the base station to show the number of each button in the order it was received. So rather than just getting a display of who buzzed in first, you can see the chronological order in which all eight buttons were pressed. Coming up with clever applications for this capability is left as an exercise for the reader.

Of course, there’s more than one way to build a buzzer. If you don’t like the way [Flute Systems] did it, then check out this version that uses 900 MHz radios and an OLED to show the results.


En aquesta pàgina teniu instruccions per fer sons amb un piezoobuzzer (brunzidor) fent servir les funcions tone() i notone() amb Arduino
Set
03

Arduino quiz show buzzer

arduino, buzzer Commenti disabilitati su Arduino quiz show buzzer 

QuizBuzzer

This nicely-built quiz game buzzer system is Arduino-based and captures the fastest player or “first to respond” out of four players.

A good friend of mine who’s a teacher was doing quizzes in her class making students compete to answer questions… resulting in them complaining they raised their hands before the others. I decided to give her this quiz show type buzzer for Christmas to solve her problems. When one of the players press it’s button (the fastest player wins this), the led of the right colour lights up saying he’s in control… and no other buttons from the other players work, until the master of the game decides if the answer is good or not by pressing a little button on the main unit, giving a point or not to the player in control.

Arduino quiz show buzzer - [Link]

Dic
26

Buzzed Buzzer gives you a Breathalyzer test while ringing in the new year

alcohol sensor, arduino hacks, breathalyzer, buzzer, mq-3, New Year's Eve, Teensy Commenti disabilitati su Buzzed Buzzer gives you a Breathalyzer test while ringing in the new year 

alcohol-sensing-party-buzzer

We’re not sure if there’s enough time to get a parts order delivered, but no geeky New Year’s party will be complete without a party buzzer that doubles as a Breathalyzer. The Buzzed Buzzer hides all of the necessary bits inside of a paper and plastic party favor. We guess it only buzzes if you’re over the limit? Actually that’s not the case at all. The accuracy of the sensor used in the project really just measures the presence of alcohol and can’t quantify BAC.

A Teensy 2.0 microcontroller board drives the project. Powered by a Lithium cell, it monitors an MQ-3 Alcohol gas sensor and drives a buzzer. The components are just small enough to be hidden by the cone of the party buzzer. You can see a demonstration of this in the short clip after the jump.

This is a fun project, but we’re still big fans of getting the crowd involved with this large LED meter which is hooked up to the same style of alcohol sensor.

[via Dvice]


Filed under: arduino hacks

This is part of a series titled “Getting Started with Arduino!” by John Boxall – A tutorial on the Arduino universe. The first chapter is here, the complete series is detailed here.

Welcome back fellow arduidans!

This chapter we will examine piezo buzzers, continue with our alarm clock, and then spend more time with the wireless radio modules by creating some remote control systems and sending various data over the airwaves. So let’s go!

Sometimes you would like to make some noise. For warnings, fun, or to annoy people. A very simple and inexpensive way to do this is with a piezoelectric buzzer. In simple terms, it contains a disc of metal that can deform when a current is applied to it. If you apply an alternating current at a high enough frequency, the disc will move fast enough to create a sound wave, something we can hear.

This is an example of a small piezo buzzer:

bzzzzz

This example was very cheap, less than $2.  Here is the data sheet: PS1240.pdf. It can run from between 3 and 30 volts AC – which thankfully the output from our Arduino falls between. But how do you output AC from an Arduino? There are several ways, however the easiest is using pulse-width modulation (PWM). If you look at your Arduino’s digital output sockets, some are labelled PWM. Using the function analogWrite(); you can send a PWM signal to the buzzer. For example:

/*
Example 13.0
Drive a piezoelectric buzzer with Arduino
http://tronixstuff.wordpress.com/tutorials > Chapter 13
*/
void setup()
{
     pinMode(11, OUTPUT);   // sets the pin as output
}
void loop()
{
     analogWrite(11,128);
     delay(500);
     digitalWrite(11, LOW);
     delay(500);
}

The sketch above will beep the piezo on and off, and be somewhat annoying. Perfect. However with the analogWrite(); function it is impossible to use the full frequency range of the piezo buzzer. With a value of 254 for the duty cycle, the frequency generated is around 1500 Hz:

Later on we will explore ways to create a better range of sounds. But now to use that buzzer in our alarm clock to help wake people up.

Continuing on from exercise 12.1, this chapter we will add some more features to the clock. First of all is the piezo buzzer. As we just discussed above, using it is quite simple. On the hardware side of things, we can replace the resistor and LED connected between digital pin 6 and ground with our piezo buzzer. On the software side of things, instead of digitalWrite(6, HIGH); we use analogWrite(6,128);. Very easy. And here is a short video – with sound!

Moving on, it’s time to clean up the alarm function in general. Most alarm clocks have a snooze function, so let’s add one as well. When the alarm sounds, the user presses button four to turn off the buzzer, and is then asked if they want to snooze. Button one is yes and four is no. If yes, add ten minutes to the alarm time and carry on as normal. When adding the ten minutes be sure to check for increasing the hour as well, and also take into account the jump from 2359h to 0000h (or 2400h). If the user presses no, the alarm is switched off and the user warned with the flashing “OFF”.

Example 13.1 – Here is a demonstration of what I came up with:

and the accompanying sketch: example13p1.pdf. The hardware is the same as exercise 12.1, except the LED and resistor from digital pin 6 to GND has been replaced by the piezo buzzer as described earlier. You will find the snooze function is controlled in the checkalarm(); function in the sketch.

In chapter eleven we started to examine the inexpensive serial data transmitter/receiver pairs. In this chapter we will continue working with them, to create the backbone of various remote control and data transmission ideas for you to use.

Example 13.2

First of all, a simple remote control with four channels. That is, it has four buttons, and the transmitter will send out the state of the four buttons, high or low. This would be useful for a remote control toy or a perhaps robot. The sketches are quite simple. The transmitter reads the buttons with digitalRead(); then transmits a single letter a~h – which is code for a button and its state. For example, a means button 1 is low, h means button 4 is high. The receiver just decodes that a~h code and sends the result to the serial monitor window. Here is the sketch for the transmitter – tx.pdf and receiver – rx.pdf.

To save time I will use the button board created in example 12.3. Here are the schematics for the transmitter and receiver sections:

And set up:

And finally a video of the serial monitor showing the button states:

Now that we have the data being sent across, let’s get some switching happening.

Example 13.3

Using the same transmitter system as example 13.2, we will turn on or off four LEDs at the receiving end. Of course you could use relays, transistors, 74HC4066s, etc instead. Our sketch (ex13.3rx.pdf) decodes the transmitted data once more, but sets the digital pins high or low depending on the received code. Here is the schematic for the new receiver:

… and the board laid out:

And again a quick demonstration video:

Now that you can turn the LEDs on or off with a push of a button, there are a few other ways of controlling those digital outputs with the remote control rig without altering the hardware.

Example 13.4

This time, we will control two digital outputs with the four buttons, as each output will have an on and off button. Consider this sketch; and the following demonstration video:

So there you have various ways to control digital outputs and send basic data across a wireless radio serial data link. In the coming chapters we will examine sending more detailed data, such a numbers, and more complex variables using a faster and more reliable hardware link.

Well that is another chapter over. However, as usual I’m already excited about writing the next instalment… Congratulations to all those who took part and built something useful!

Please subscribe (see the top right of this page) to receive notifications of new articles. High resolution photos are available from flickr.

If you have any questions at all please leave a comment (below). We also have a Google Group dedicated to the projects and related items on the website – please sign up, it’s free and we can all learn something. If you would like to showcase your work from this article, email a picture or a link to john at tronixstuff dot com. You might even win a prize!

Don’t forget to check out the range of gear at Little Bird Electronics!

So have fun, stay safe and see you soon for our next instalment, hopefully by 7th August 2010.



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