Tag Archives: TrH meter


Support us by preordering TrH Meter kit on Tindie

Assembled TrH Meter

We are now accepting pre-orders for the TrH Meter kit through Tindie’s fundraising program, a new feature that they announced a couple days ago. Our target is to receive 20 orders by Dec 31st. So if you pre-order it now, you will get a complete TrH Meter kit for a discounted price of $25 and a thank you note from us for your support in making this funding campaign successful. You will receive a preprogrammed PIC16F688 microcontroller with the kit, which means the kit is ready to go right out of the box.

Assembled TrH Meter

“TrH Meter is a DIY microcontroller-based indoor thermometer plus hygrometer that displays temperature (F/C) and relative humidity on 4 seven segment LED displays which adjust their brightness level according to the surrounding illumination. The displays are 1 inch big, emits bright yellow color, and are readable from more than 50 ft away. It consists of a closed loop system that continuously assesses ambient light condition using an inexpensive light-dependent resistor (LDR) and uses that information to adjust the brightness of the display. The DHT11 sensor is used to measure temperature and relative humidity. The microcontroller used in this project is PIC16F688, and it runs at 4 MHz internal clock. A separate display driver chip (MAX7219) is used to control and refresh the display data on the seven segment LEDs. A 3-position slide switch controls power ON/OFF and Fahrenheit (F) or Celsius (C) scale select for temperature display.”

TrH Meter kit for only $25

Board dimensions are approximately 3.9" X 3.1" (10cm x 8cm)

Support us by pre-ordering a TrH Meter kit here: TrH Meter kit Preorder Link

TrH Meter: A DIY indoor thermometer plus hygrometer with adaptive brightness control implemented to 7-segment LED displays

TrH Meter

This project is about building a microcontroller-based digital room thermometer plus hygrometer that displays temperature and relative humidity on 4 large (1 inch) seven segment LED displays which adjust their brightness level according to the surrounding illumination. It consists of a closed loop system that continuously assesses ambient light condition using an inexpensive light-dependent resistor (LDR) and uses that information to adjust the brightness of the display. An inexpensive DHT11 sensor is used to measure temperature and relative humidity. The microcontroller used in this project is PIC16F688, and it runs at 4 MHz clock generated from its internal source. A separate display driver chip (MAX7219) is used to control and refresh the display data on the seven segment LEDs.

TrH Meter: A DIY indoor thermometer plus hygrometer

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