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eMariete
  • Home
  • Radioactivity Madrid
    • Ionising radiation in Madrid
    • Weather station
  • CO2 sensors
    • The CO2 sensor bible MH-Z19B
    • Sensirion SCD30 dual-channel NDIR CO2 Sensor
    • Winsen Low Power NDIR CO2 Sensor MH-Z1311A
    • Comparison CO2 sensors MH-Z19B vs Senseair S8
    • Sensirion SCD41 and SCD40 CO2 Sensors
    • CO2 Sensors MH-Z19B FALSE
  • CO2 Easy
    • Build the home CO2 monitor with Wifi
    • Uses the Senseair S8 sensor in the CO2 Meter
    • Gallery: Users' CO2 Easy meters
    • 3D printed enclosures for CO2 meter
    • Add an OLED display to the meter
    • Adds temperature, humidity and atmospheric pressure
    • Are home CO₂ meters as reliable, accurate and precise as commercial ones?
    • Full colour touch screen for CO₂ meter Wow!
    • Adds buzzer alarms to the CO2 meter
    • The CO2 meter on a large display
    • CO2 on a giant screen for bars, restaurants, classrooms and the like.
  • CO2 Gadget
    • CO2 Gadget: Advanced CO2 Monitor
    • CO2 Meter TFT Colour Display with TTGO T-Display Sensirion SCD30 - The CO2 Gadget
    • CO2 Gadget Low Power CO2 monitor with Lilygo TTGO T5 ePaper and Sensirion SCD41 Sensor
    • CO2 Gadget Boxes, 3D Printed and without 3D printer
  • en_GBEnglish (UK)
  • es_ESEspañol

PWM

Generating variable voltage with Arduino, ESP8266 and ESP32

5 January, 202413 December, 2023 by Mariete

Let's see how we can generate a variable voltage with Arduino, ESP8266 and ESP32 using different techniques.

Categories Electronics, Projects with Arduino Tags Arduino, ESP32, ESP8266, Experiments, NodeMCU and Wemos D1 Mini, PWM Leave a comment

eMariete PWM Mini Hat for Raspberry Pi

26 December, 20232 December, 2023 by Mariete

Build a small Hat for Raspberry Pi to easily connect a fan, LEDs, a motor or whatever you want!

Categories Raspberry Pi Tags PWM, Raspberry Pi Leave a comment

Tutorial: Temperature-controlled variable speed fan for Raspberry Pi

3 December, 202327 November, 2023 by Mariete

Do you, like me, want to reduce (or even eliminate) the annoying noise of the Raspberry Pi 4 fan? If so, here is the ultimate solution. Easy and cheap.

Categories Electronics, Raspberry Pi Tags PWM, Raspberry Pi 4 Comments

PWM driver with MOSFET transistor

3 December, 202323 November, 2023 by Mariete

Learn how to build, and how it works, a PWM driver with a MOSFET transistor!

Categories Electronics Tags Experiments, PWM 1 Comment

How to use a MOSFET as a switch?

10 December, 202323 November, 2023 by Mariete

Learn how to use a MOSFET as a switch and go to the next level!

Categories Electronics Tags Experiments, PWM Leave a comment

PWM driver with BJT transistor

24 November, 202317 November, 2023 by Mariete

I will explain how to build, and how it works, a PWM controller or driver with a "normal" bipolar transistor.

Categories Electronics Tags Experiments, PWM Leave a comment

How to repair your switching power supply

20 November, 202313 November, 2023 by Mariete

Do you need to repair your switching power supply? Here's how you can repair a malfunctioning power supply yourself.

Categories Electronics, Repair Tags Power supplies, PWM, Repairs 5 Comments

Controlling the speed of a fan with PWM

20 November, 20231 November, 2023 by Mariete

We are going to see how to control the speed of a fan with PWM. What it consists of and why to do it this way.

Categories Electronics Tags PWM, Raspberry Pi, Theory Leave a comment

What is a PWM (Pulse Width Modulation) signal?

13 December, 20231 November, 2023 by Mariete

PWM signals are increasingly used in computers and microcontrollers (Arduino or ESP8266). Let's see what they are in an understandable way!

Categories Electronics Tags PWM, Theory Leave a comment
DO YOU HAVE DOUBTS? QUESTIONS? PROBLEMS?

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