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From the mail bag…


From the mail bag…

I’d like to say that I’ve had a very positive experience with the RGB backlit LCD.

I have incorporated it into an Arduino-based dual-stage temperature controller that keeps a refrigerator at whatever temperature I set it with a front-panel switch (used for brewing beer).  When the temperature is within 1 degree of the setpoint, the display is green.  When it turns on the 110VAC to the cooling outlet (fridge power), it turns the display blue, and when it turns on the heating outlet (40W light bulb), it turns the display red.

It’s a great application for that display and has impressed a few people. I’d be willing to share some pictures if you’re interested. It uses three of your TMP36 sensors and an Uno.

p.s. It also incorporates an XBee so I can control the temperatures remotely (it’s in another building), but I can receive ambient air, ambient fridge air, and carboy temperatures for logging.  Remote control is handy because of the temperature fluctuations required for lagering that take place over the course of days.  Might as well automate that instead of walking out and manually changing the setpoints, right?  🙂


You can get the RGB LCD(s) here, here and here.

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  1. Mike,
    That’s a really great idea. Nice looking project. Thanks for the inspiration.
    (update with beer pictures when available?)

  2. Great project and I would love to build one also. I’m also a brewer. Will you share your design?

    pgrunwald AT

  3. Great job, my friend! Can’t wait to taste the beer 🙂

  4. Ditto- nice project! By the way, would you mind sharing your source for the nice bezel you used for the LCD display?
    (Gee, I sure wish Adafruit Industries had those! hint..hint)

  5. Very nice – I have been looking for just this type project for a growth chamber I am building. As above will you share the design?

  6. I saw this and was highly impressed. Nice work.
    I am also a Homebrewer and was wondering if you would be willing to share the planes to it.

  7. very cool . . . could this also work for a humidor ? It would need 70f degrees and 70% relative humidity

  8. I just ordered a display and sensors from here. I already have a Duemilanove 328. I ordered this relay board

    I don’t plan on doing wireless but I did get the high density display so I can graph.

    I will post more when I’m a little further along.


  9. p.s. Junction Box can be found at Lowes:

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