Smoker Fan Controller V2

The first version of the board worked well for what it is. Problem is I didn't have enough Max6675s. And I really wanted WiFi on this project. So here's rev 2, changes include:

- swapped all the power components to SMD and had jlcpcb assemble them.

- changed thermocouple connectors to audio jack connectors

- added debug let's

- added connector for esp01, power controlled by a fet

First pic is the pcb i received from jlcpcb. Second pic is fully assembled. For the most part the pcb worked great, only 2 issues. One was that the led's were placed backwards and need to be fixed by hand. Second is that I chose the wrong fet to power the esp01, luckily I had some other parts in the same footprint that worked.

Now that I had wifi on the board. I was able to update the code to monitor the meat smoking remotely. I used the Blynk app/framework to do this, which is honestly a way better visual than the LCD.

Smoker Fan Controller

Its been a while but multiple projects are in the works. Currently working on a fan controller for my meat smoker. I acquired a free charcoal meat smoker and I need a way to better control the temps. Also using this as an excuse to learn KiCad. I also just switched over to using PlatformIO as my IDE and this is the first project that I'm using an stm32(blue pill board) over an arduino nano. So alot of new factors.

For the design I wanted to use an existing LCD I had from my old 3d printer, aswell as some thermocouples to handle 200-400 degree heat, and a mosfet to control a fan that i bought specifically to fit a smoker. 

So here is my first go with KiCad. Drew everything up, exported the Gerber files, and had these made from jlcpcb.com. They only cost $12 with shipping for 5 boards, great value!

KiCad PCB View

Bare PCB

A pic with parts soldered on the board. Powered and fan connected.

While everything worked on the pcb, I'm already working on a v2. Figured out the max6675's were obsolete and the max31855's are not compatible with the pcb(not 5v tolerant). Also want to add WiFi and MQTT support. 

Smart Bedframe

Recent gap in posts is due to moving. Now going from a 1 br apt to a house, there are plenty of new things to automate. First project is to make a light controller for the bedroom. 

I want this device to control: 

- RGB led strip under the bed

- White led strip under the bed

- 2 dimmable lights connected to the headboard

I had planned to just use a nodemcu but due to the mosfets and 2 AC dimmers all requiring a PWM signal. I had to go with an Arduino nano paired with an ESP01. Sounds easy enough... but I vastly underestimated how much extra code that added to the project. In retrospect I would probably go with a bigger espressif board. Here is a pic of how I layed out all the boards in fritzing and then physically layed out.

And here it is fully wired up. Code is 95% ready. The ESP can connect to the MQTT server and relay commands to the Arduino Nano.

And now it is installed on the bedframe under the mattress. The 3d printed box pictured is a housing the cover up a screw terminal for the AC and 12v lines.

Biggest hiccup in this project is the AC dimmers library uses internal timer 2, which prevents you from using 2 of the 5 PWM signals. I solved this by just using a digital signal for the RGB mosfets, so I just can't dim the RGB colors anymore. Not a big deal.

Adding Wifi to a Dumb RGB Light Bulb

Many years ago I had bought a RGB led bulb off amazon to try out, when there really wasnt a smart bulb market. After collecting dust more many years it has found a use! I moved into a new apartment and the foyer light was burnt out, i tried like 4 different LED and non-LED bulbs, and this cheapo RGB bulb was the only one that worked.

Problem with this bulb is when you turn it on, it comes on red and you have to use the IR remote to change it to white....  I really dont want to use a remote, so time for an upgrade. Luckily I had a ESP micro laying around, specifically a Wemos D1 mini. This is also a great opportunity to add another device to my home automation system. The plan is to have this device communicate using MQTT to a raspberry pi running Openhab.

Steps to put a new brain in the light bulb:

• Pull off plastic cap, pry original PCB from aluminum housing(just glued down with some sort of thermal glue).
• De-solder the original IC, oscillator, and IR receiver led.
• Wire the original DC power wires into the wemos and add new power wires between wemos and led board.
• Add 3 wires between wemos and led board for red, green, and blue control.
• Program custom code(Github link). I used the Arduino IDE and the following libraries:
• ESP Wifi
• MQTT
• OTA downloads

Board stack showing wemos under RGB led board.

Wires soldered onto the pads of the existing IC.

Update: In retrospect I should have just used the really nice tasmota software available for free and created a custom config.

Brewpot water level sensor

Working on a new addition to the homebrewing setup. I want to be able to detect water/beer levels in the pot. This circuit will read multiple probes to detect which ones are in water and report the status back to the raspberry pi over the usb serial connection.

I started with a simple circuit I found online, then added my own twist. Had to relearn eagle cad, then sent the eagle project file to Oshpark to get some PCB's made.

Schematic

Board Layout

Final PCB assembled(mostly)

   

Next step will be to get my 3D printer working so I can print the following enclosure that I drew up in Fusion 360.

Bcd Clock Build

This is my BCD(binary coded decimal) clock. Built with an atmega168 mcu(like the arduino), ds1307 rtc, and 3 74hc595 shift registers. Added a cp2102 chip for the usb interface so the clock can be configured by a computer.