Voltlog #275 – CO2 Concentration Measurement System With MH-Z19B & CCS811

Welcome to a new Voltlog, you might remember these two sensors from a previous mailbag, this is the MH-Z19B and this is the CCS811 both of these report CO2 levels but they measure this differently and I’ll explain this in a moment. I got these two sensors in order to monitor CO2 levels in my home, to determine if the levels rise too much at night, especially during the winter time when we tend to keep the windows closed most of the time. I live in an old apartment building where there isn’t much provision for ventilation and so I suspect the air I breath during sleep is high in CO2 levels as it builds up over night.

In this video I’m gonna show you how I built the monitoring system using an ESP32 board that reads the sensor data and then sends it over the network to an MQTT server running on my raspberry pi. I then use node-red to insert the data into InfluxDB and then finally Grafana to monitor all of this data in a nice graphical user interface. The beauty of this setup is that all of this software is free to use and open-source.

Voltlog #274 – Installing Traccar GPS Tracking Server On A Raspberry Pi

Welcome to a new Voltlog, today I’m gonna show you how to setup your own GPS tracking server on a raspberry pi. It doesn’t have to be a Raspberry pi, because the software that we’re going to be using for the tracking server is available for Windows and Linux as well, so you could host this on your windows machine or in a virtual machine on a cloud service, it’s up to you, but in this video I’m going to do it on a Raspberry pi 4.

The idea started a couple of videos back, in Voltlog #272 when I got this GPS tracker disguised into a general purpose automotive relay. In theory this should come with free online tracking service on some Chinese hosted server but I wasn’t able to connect to that server and so I thought why not setup my own server and try to pair it with this tracker. So if you want to learn more about this tracker, checkout Voltlog #272 linked on screen right now and then come back to watch this video.

First step is to setup a fresh install of Raspbian, latest version from the source. Next step is to setup the tracking server, the name of the software is Traccar and here is their website. We’re going to be using the Linux arm release, because the raspberry pi runs on an arm processor. Next, your raspberry pi is likely sitting behind a router or firewall so you will need to forward a port so an external device like a GPS tracker can connect to our newly created server.

Next we can add our GPS tracker in the web interface of Traccar, on the left side I click add, choose a name for your device and fill in the 10 digit identifier which is this label on the side of your trackers case.The newly created device will be shown as offline until the server starts receiving data.

The final step is to configure the GPS tracker and these particular commands apply to the tracker that I am using, you might have to use different commands for a different tracker but the idea is to reset the tracker, set your admin number, configure the APN settings for your network operator, set the external ip address we saved earlier, the port is 5013. Set the upload frequency in seconds and enable the GPRS connection. Going back to the Traccar web interface, status should switch to online and we should start seeing data about our device.

Voltlog #273 – InTheMail

Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. Before I get started I’m gonna take a second to reminding you to subscribe to the channel and hit the bell notification icon because that’s the only way you will know for sure when I upload new videos. Now let’s start with this small esp32 based development board, it has a built-in 1.14 inch color tft lcd and I think that’s a nice feature of this dev board because if you want to connect some sensors and see the readings in real time, you don’t need to wire a display externally it’s built-in.

Another cool feature is that we have built-in battery charging at 500mA and you can power this board through the provided two pin jst connector with a one cell lipo battery which will then charge when connected to power via the USB Type-C port. There is also a CP2104 for the usb to serial conversion and that makes it a pretty well balanced development board for the ESP32.

The board comes loaded with a test program from TTGO, it shows this image then cycles through red, green, blue on the LCD which is a good idea because you can verify the board is functioning ok after the long journey it takes from the market in shenzhen to your door and we all know how well these packages are protected during shipping.