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By pranaman

I have an idea for something that will beep when boiled water cools to a certain temperature. Thinking it will have circuitry and a simple interface to allow me to set a desired temperature, like 50 deg F, and beep when desired temperature is reached

I see, which seems it could be a big part of this, and where I see it connected to a circuit and has a readout.

Does anyone know how I can:
get the circuitry part?
set a desired "after boiling" temperature - maybe start at 50°, and have up and down arrows, allows it to be changed by 1° F at a time?
have it beep when it reaches the desired temperature?
By jremington
For "circuitry" you will need a microprocessor, with a display, pushbuttons and a buzzer.
Pololu makes just such items in a single, small package.

Plenty of Arduino code is available on the web to read the temperature sensor, display values, read pushbuttons, etc.
By pranaman
Thank you for suggesting that. I found another way, with an arduino uno and a DS18B20, a waterproof digital temperature sensor, and followed ... ino-9cc806.

I am able to read water and air temperature. I also have:
> a 0.5L Mini Kettle
> an LCD 1602 Blue screen 5v module
> a dial resister that someone gave me
> a buzzer

Found my ideal temperature to be ~ 40C or 100F.

Next, trying to put it all together.

First idea, Part A:
Turn on kettle, let it boil water. Have sensor end in the kettle.
Seems it auto shuts off, so let it do that.
Once it drops and reaches 40C/100F, which I can have in code, beep

then, get fancy, Part B
Connect the sensor with the circuitry in the kettle.
Allow for customizable temperatures with a dial or up/down buttons
Keep the temp within +/- 2 degrees, if it gets too low, so it's always in the desired range, by turning the heating element on and off

Firstly, getting to Part A. I've got the concept any idea how to modify the code and how to add the buzzer and LCD to get Part A?
By jremington
Plenty of tutorials for all of those things on the web.
Get each part of the project (LCD, buzzer, etc.) working separately, and understand each example completely, before you merge them all together.