Below is the circuit diagram and PCB layout of the FM wireless microphone: The FM broadcast band has a frequency range of 90MHz (MHz = megahertz or 90 million cycles per second). Since the FM microphone has a variable tuning circuit, it can be tuned to a quiet location on the local FM broadcast band […]
Category: Video
Stereo audio control circuit based on LM1036
This is an IC based stereo audio control circuit LM1036. This circuit will control the bass/treble level tone, volume and balance between the right and left channels (inputs 1 and 2). You can use this circuit for stereo applications such as car radios, TV and audio systems, mp3 players, dvd players, ipods, etc. Additional control […]
Take a look at the driver framework provided by Linux for the camera
forewordEarlier we learned about the basics of some cameras “Camera Basics”. Let’s take a look at the driver framework provided by Linux for the camera. Introduction to V4L2 V4L2 （Video Linux Two）, is a driver framework driver framework designed to support the Linux kernel. The operation interface layer (ioctl) set for the application is to […]
Camera driver analysis of Linux kernel
Camera driver analysis Linux version：4.19 Sensor: OV13850 (1) Load and unload functions//DTS match tablestatic const struct of_device_id ov13850_of_match[] = {{.compatible = “omnivision,ov13850-v4l2-i2c-subdev”},{},};MODULE_DEVICE_TABLE(i2c, ov13850_id);static struct i2c_driver ov13850_i2c_driver = {.driver = {.name = ov13850_DRIVER_NAME,.owner = THIS_MODULE,.of_match_table = ov13850_of_match},.probe = ov13850_probe,.remove = ov13850_remove,.id_table = ov13850_id,};module_i2c_driver(ov13850_i2c_driver);OV13850 is controlled by I2C interface, so use i2c_driver for registration.(2)probe()static int ov13850_probe(struct i2c_client […]
Compared with mobile phone APP control, what are the advantages of SR101 voice remote control?
The surface has continued to heat up this summer, and 2022 has also managed to rank among the top ten hottest years. Global temperatures have risen, even reaching a rare 32.5 degrees in the Arctic. In this context, air conditioners have become a must-have anti-heat artifact in summer, and sales of electric fans have also […]
PCB-based 64-key prototype keyboard matrix
This is a simple PCB keyboard that you can easily use for your Arduino projects. I’m currently working on a project that will have an integrated keyboard, and I’m running into a problem: how do I include a keyboard in my board prototype? I can’t use a USB keyboard or an existing Arduino based keyboard […]
Audio player built on ESP32
DIY music players are fun, we’ve built some before using an Arduino and a dedicated MP3 module. Now we’re building an interesting audio player using the ESP32 where you can play sound effects by simply connecting an extra speaker to the ESP32. Here we will use LM386 and a speaker with ESP32 to play music […]
Use ESP32-CAM to build a digital door lock system controlled by face ID
Security is the number one concern of everyone today, whether it’s data security or the security of one’s own home. With the advancement of technology and the increasing popularity of the Internet of Things, digital door locks have become very common these days. The digital lock does not require any physical key, but it uses […]
How to Build a Gesture-Controlled Elevator Prototype Using an Arduino Nano
During this time of the coronavirus pandemic, elevators have become high-risk places where everyone touches the same buttons. In many places, people have found tricks to prevent touching the elevator buttons, such as using tissue, toothpicks or toilet paper to press the elevator buttons. So, to continue our previous Corona safety projects like automatic sanitizers, […]
How Designers Can Leverage New Car Audio Technology for Active Noise Cancellation
Drivers in the new vehicle market are actively seeking quieter vehicles that provide a superior communication experience between passengers and the outside world. With increased electrification, cars have become quieter; however, in these quiet cars, especially at high speeds, passengers typically hear more outside noise than in noisy combustion-engine cars. To further reduce cabin noise, […]