How to Activate 5v Active Alarm Buzzer From Transmitter
Buzzers for quadcopter is one of the most basic hardware in the hobby, but a few beginners are still getting confused. So hopefully this article can help clarify a few things.
Don't forget to check out our quadcopter building tips and tricks.
Purpose of buzzer on a quadcopter
- Lost model alarm – it helps you to find your quad very easily after crash
- Low voltage warning – buzzer goes off when battery voltage is getting low and should land
- Quad status – the beeping can help you identify the state the quad is in
Buzzer Choice – Don't get the Wrong One
There are 2 types of buzzers, Active and Passive. YOU NEED ACTIVE BUZZERS!
Basically, active buzzers beeps as soon as you give it DC voltage, while passive buzzers require an AC "sound signal" for it to generate sound. Quadcopter flight controllers usually support 5V 2-pin active buzzer/beeper. These buzzers are cheap, light weight and widely available online.
Standard Active Buzzer
This is the basic 2-pin active buzzer that should work on almost all flight controllers. The max volume is about 89dB at 20cm distance as I tested.
- Amazon: http://amzn.to/2t9dM6K
- Banggood ($1.6 for 5): http://bit.ly/2uw8Cp4
Mini Buzzer
For smaller models or space/weight saving, you can get these "mini" buzzers. The only downside is volume, at about 86dB at 20cm distance.
- Banggood: http://bit.ly/2Mfq2iT
Buzzers with Built-in Battery
If you crash and the battery gets unplugged, normally your buzzer will stop working as it's no longer powered by the flight controller! To avoid this you might want to get a buzzer with built-in battery, these are designed to continue to beep when the quad's battery is disconnected.
I did a shoot out in this post comparing the different options.
Matek PWM Buzzer
Matek makes some really cool buzzers. For example this "Loud buzzer" works as a normal buzzer, and it can also be controlled via a AUX channel (PWM signal) at the same time without the need of an FC.
And this "LED tail light buzzer" has the same feature, but it has integrated RGB LED's. It can be mounted on the back of the frame.
LiPo Voltage Checker
LiPo voltage alarm/checker also has built-in buzzers, but they are only meant to give you warning on low battery voltage and nothing else. They are connected to the balance lead of your LiPo battery. Here are other ways of monitoring battery voltage.
This is a voltage alarm, not a buzzer
How To Install Buzzer In a Drone?
An active buzzer has two pins, one positive pin and one negative pin.
The positive pin is normally longer, and if there is already a wire soldered to it, it's red.
Most flight controllers have dedicated solder pads for connecting the buzzer, normally labelled as B+ / Buzzer+ and B- / Buzzer-.
Simply solder the red wire or longer pin to the Buzzer+ pad on the FC, and solder the black wire or shorter pin to the Buzzer- pad on the FC.
For example:
Active buzzer and flight controller Connection example
Configuring Buzzer in Betaflight
In Betaflight's Modes page, scroll down until you see "Beeper", and assign a switch to activate it. In this example, my switch is AUX 2, which is channel 6. To learn about how to setup switches in OpenTX see this tutorial.
You can also turn beeper off for certain conditions if you find it too annoying. Beeper Configuration is located under the Configuration page. For example you might want to disable beeper for USB, so it doesn't beep when you are working on the quad on the bench.
How to make buzzer louder?
- Connect multiple buzzers in parallel, for example.
- Use higher voltage rated buzzer, and provide higher voltage to it, such as using 12V in this example.#
How to make buzzer quieter?
If you don't like how loud these buzzer is, you can simply put a resistor in series to the positive or negative pin. This will reduce the current flowing through it and lower the volume. The larger resistor the more effective it will be.
Buzzer Alternative?
As a lost model alarm, you could setup your ESC beeping as an alternative to buzzer: Using ESC Beacon as a lost model alarm
Edit History
- Jul 2017 – Article created
- Aug 2018 – Added Mini Buzzer
How to Activate 5v Active Alarm Buzzer From Transmitter
Source: https://oscarliang.com/buzzer-quadcopters/