Category: Uncategorized

Recently my garage beverage refrigerator decided to break. The condenser would either never run, or never turn off. So either everything was room temperature (yuck), or frozen no matter how we set the internal thermostat.

After a few weeks of room temp beverages I decided it was time to fix this.

I dug in my miscellaneous parts drawer and pulled out an Arduino and also found a DHT11 temperature sensor.

The Arduino I found was an UNO R4, it is more recent and has a small built in LED array and built in WiFi. Arduino’s can now be programmed from a cloud site so no need to download much more than a simple USB driver.

In a few minutes I had a simple Sketch that would read the temp from the sensor and output to the LED.

It was pretty straight forward to add a temp that we would need to turn off the refrigerator and a couple degree dead band before it turns it back on. I found that the sensor was a few degrees high in the measurements and also only accurate to 1°C at a time. I altered my set points, so the LED display is 3-4°F high.

I also had a spare Kasa Smart plug to plug into the fridge to help control it. However the Kasa has no public APIs to directly control it from the Arduino.

A few Google searches lead me to this post for a way to mimic what the Kasa phone application does to control the switches.

The Ardunio has WiFi capabilities built in so simple enough to code a PHP page to toggle the switch on and off. Using the example code I had the UUID of my device and the PHP page built to toggle it on/off added to the sketch.

Since I had to code the ability to call a website I might as well create a page to log the temperature readings every 15 minutes. And using that data show a nice graph on a webpage as well.

So now the sketch will check the sensor about every 30 seconds, it will update the LED when the temp changes and every 15 minutes log the current temp to the server. If the temp goes above the set point dead band temp it will turn on the fridge via the Kasa Smartplug and turn it off when the temp goes below the set point.

Every 15 minutes it also retriggers the Kasa smartplug just to make sure it is in the state that the Arduino expects it to be in.

The sketch can be downloaded from here if interested. And the temp logger and graph PHP is here. Note: the URLs have been changed, so no need to try to spam my logger. 🙂

Next up is a 3D printed case to properly mount it on top of the fridge. All in all a fun project and best of all a working beverage fridge again.

Time Ships by Stephen Baxter
This is a “sequel” to HG Wells classic, Time Machine. It picks up immediately after the main character returns to his original time. In this version he makes several trips into the future and sees how his interactions in the future and past impact his reality. A notable book and a fun read but not a lot of “meat” for character development.

Later by Stephen King
A decent read about a boy/man with an unusual “6th sense” talent. He is recruited by a detective to help solve a crime and in doing so he learns a few things about his life.

Solis by A.A. Attanasio
An interesting sci/fi that deals with the ability to upload a brain into a computer. In this version these frozen brains become property and essentially slaves stuck in a computer. In this tale one of these “slaves”, with the help of a few unlikely characters, runs away to build his own life.

Pathfinder (Pathfinder #1) by Orson Scott Card
Rigg has a strange talent for seeing the paths of people’s pasts. A tragedy in his life forces him onto a journey to learn more about himself, find some family and learn about the world he is part of. This series does a good job of world building. Intriguing enough to real the whole 3 book series.

Ruins (Pathfinder #2) by Orson Scott Card
Building upon book one now Rigg ventures into another previously closed off part of his world and learns more about the fate he needs to help prevent.

Visitors (Pathfinder #3) by Orson Scott Card
Rigg’s journey comes to an epic and explosive conclusion as everything that has been building up finally comes to pass.. If you have read any previous work by Card I would recommend giving this 3 book series a try.

Billy Summers by Stephen King
This was an excellent book and unlike most King books there little to no paranormal aspects to the book. The MC is a killer for hire doing a final job that goes sideways. How does he finish the job, get paid so he can retire? I enjoyed this book and recommend giving it a try.

Jack of Shadows by Roger Zelazny
Crazy book about a far future where the earth no longer spins and has a light and dark side. However magic rules these regions. Jack, is Shadowjack the Thief, who broke the Compact and duped the Lord of High Dudgeon wants to rise up to seek vengeance upon his enemies. Weird but short, fun read.

Witch’s Reign, Dragon’s Ground, Jinn’s Dominion, Oracle’s Haunt, Wyvern’s Lair, Emperor’s Throne (Desert Cursed series) by Shannon Mayer
A young adult series about a girl shape shifter who was part of a lion’s pride, a groups of shifters that turn into lions. However she can only change into a house cat. In the series of course she has to try to save the world, but along the journey finds her past, her family history and why she is just a housecat. Can she find out about herself, find her remaining family and save the world? Quick reads since they are targeted for the YA crowd, but a tired hero story line.

Duplex (Micropowers #2) by Orson Scott Card
The micropower series is excellent and a new take on super powers. These books focus on useless powers like the ability to find something that is lost (see book one), or someone who can sense if someone has an innie or outie belly button. Yet these micro power folks need to get together to battle a bad group of people.