Summary of Dead Simple Ultrasonic Data Communication
Eduardo Zola demonstrates a simple one-way ultrasonic data communication system using two Arduinos and HC-SR04 transducers. The transmitter converts ASCII text to binary tones, while the receiver uses an LM386 amplifier and LM393 comparator to decode signals back into text. This basic setup allows serial string transmission between computers with minimal components.
Parts used in the Ultrasonic Data Communication Project:
- Arduino microcontroller (transmitter)
- Arduino microcontroller (receiver)
- Ultrasonic transducer from HC-SR04 module
- LM386 amplifier
- LM393 comparator
Some of the best hacks are the ones which seem perfectly obvious in hindsight; a solution to the problem that’s so elegant, you wonder how it never occurred to you before. Of course we also love the hacks that are so complex your eyes start to water, but it’s nice to have a balance. This one, sent in by [Eduardo Zola] is definitely in the former group.
In the video after the break, [Eduardo] demonstrates his extremely simple setup for using ultrasonic transducers for one-way data communication. Powered by a pair of Arduinos and using transducers salvaged from the extremely popular HC-SR04 module, there’s a good chance a lot of readers can recreate this one on their own bench with what they’ve got lying around. In this example he’s sending strings of text from one computer to another, but with a little imagination this can be used for all sorts of projects.
![This one, sent in by [Eduardo Zola] is definitely in the former group](https://duino4projects.com/wp-content/uploads/2018/07/This-one-sent-in-by-Eduardo-Zola-is-definitely-in-the-former-group.jpg)
For the transmitter, the ultrasonic transducer is simply tied to one of the digital pins on the Arduino. The receiver is a bit more complex, requiring a LM386 amplifier and LM393 comparator to create a clean signal for the second Arduino to read.
But how does it work? Looking through the source code for the transmitter and receiver, we can see it’s about as basic as it gets. The transmitter Arduino breaks down a given string into individual characters, and then further converts the ASCII to eight binary bits. These bits are sent out as tones, and are picked up on the receiving end. Once the receiver has collected a decent chunk of tones, it works through them and turns the binary values back into ASCII characters which get dumped over serial. It’s slow, but it’s simple.
If you’re looking for something a bit more robust, check out this guide on using GNU Radio with ultrasonics.
- How does the transmitter send data?
The Arduino breaks strings into characters, converts ASCII to eight binary bits, and sends them as tones. - What components are needed for the receiver circuit?
The receiver requires an LM386 amplifier and an LM393 comparator to create a clean signal. - Can this project be recreated with common parts?
Yes, readers can likely recreate it using Arduinos and transducers salvaged from HC-SR04 modules. - What is the speed of this communication method?
The article states that the process is slow but simple. - How does the receiver convert the signal back to text?
It collects tones, turns binary values back into ASCII characters, and dumps them over serial. - What is the source of the ultrasonic transducers used?
The transducers are salvaged from the extremely popular HC-SR04 module. - Is there a more robust alternative mentioned?
Yes, the article suggests a guide on using GNU Radio with ultrasonics for a more robust solution. - What type of data is demonstrated in the example?
The example shows sending strings of text from one computer to another.
