Yay, mine works. Thank you Chris. This is so cool! I just need a Fahrenheit code update for my Yank brain!
I ran into a few issues so let me list them here for others. This was my 1st arduino build so these are probably all noobie mistakes!
1) I used a 4.7KW 1/4W resistor (no issue but was unsure if I should use a 1/8w or 1/4w)
2) I could not get the sketches to compile until I added the Adafruit unified sensor library.
3) I could not get the DHT22 to read any temperatures. Maybe this is due to how I wired the mono jack. I ordered mono but it appears I got stereo. Originally I had digital 10 signal going to one end of the resistor and digital 10 VCC going to the jack along with the other end of the resistor. I switched signal and VCC on the extension board and then I could read temps.
4) I could not get the display to work by following the diagram (crossing SDA to SCL). When I hooked up SDA from the display to SDA extension board (and SCL to SCL) the display worked.
5) The MOSFET was coming on when it should but I had a constantly warm heater strap. Originally, I had the heater connected to Vin and GND and the 12v supply to V+ and V-. As soon as I switched those the heater only came on when the controller told it to.
By the way, I am using 12v power source with power pole connector. It has 7x USB2.0 ports and is made by Modern Robotics in the US. IT's about $90. I plan to have an ulta light, low power imaging solution using an Intel compute stick as the PC. The stick, powered USB / 12v hub, dew controller will all mount on my scope with only 1 wire coming up to the scope. I put an inline meter off the battery output. At idle this dew controller pulls 0.5W, with 1x 3" heater strap at 100%, I am pulling 5.8W.
Happy Holidays!
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