Voltlog #294 – 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 remind 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. 

Depending on which part of the world you live in, you might be dealing with the same isolation measures as I am, the government is recommending we stay inside as much as possible here in Romania, to avoid contact with other people. So that gives me more time to work on projects, learn new stuff and of course discover and order stuff from the internet.

I’m gonna start with this notebook which has a retro looking leather cover, I think it’s quite neat looking, I’m not sure if this is real leather or not, description just said leather. I always keep a notebook around the workbench, it can be useful for drafting a quick schematic, some dimensions or just for writing down some measurements. Another cool feature of this notebook is the binder style clips you have inside, which allow you to insert or remove paper and what’s even nicer is that you can find this type of paper with different grid styles and they’re very affordable.

Voltlog #257 – ESP32 PIR Motion Sensor With Deep Sleep & MQTT (revB part2)

In this video I’m gonna show the second revision of my esp32, battery powered PIR motion sensor. This second revision contains some optimizations to improve deep sleep power consumption as well as to fix some of the errors I had the first revision of the pcb.

Voltlog #240 – ESP32 PIR Motion Sensor With Deep Sleep & MQTT

Welcome to a new Voltlog, in this video I’m gonna show you how I designed and built this board which functions as an esp32 based, battery powered PIR motion sensor. So I started by designing the circuit, I used some common building blocks, I added the ESP32 with it’s bypass caps, some test points and the programming circuit with auto-reset, I then added some connection points for the PIR sensor, an RGB LED because why not have a nice way to signal this is one of those very small digital RGB leds, it’s just 20x20mm, it’s connected to 3.3V even though it’s only rated for 5V so I’m hoping this is going to work even on 3.3, it’s also worth having a temperature/humidity sensor to also sense that in whichever room the node will be placed and finally the power supply circuit which is a simple low dropout regulator with an 18650 battery as the input.

I did not include a battery charger circuit on this module, because I wanted to keep things simple, I’ll have a battery socket so I can just remove the 18650 cell and charge it separately plus the whole circuit should run in sleep for extended periods of time giving me a long operating time so i wouldn’t have to charge the battery too often.

Once the schematic was finished I did the board layout in a hurry so it’s not exactly pretty or optimized

but I tried to move the esp32 antenna to the side, to place the PIR sensor in the top side as the module will probably sit vertically, I tried to place the temperature sensor in the bottom side to keep it away from any components that might get hot and also placed some isolation slots for the same reason.

You should check-out revB of this board, I made some improvements present in the video below.

Voltlog #168 – Polycom CX600 IP Phone and Jabra 410 Speaker Teardown

A viewer sent in a Polycom CX600 IP Phone and a Jabra 410 Speaker for a teardown and a teardown I did. The phone has this TI TNET series system on chip, I couldn’t find any info on that but it looks like it may contain an ARM11. The speaker interestingly contained a bluetooth chip even though it doesn’t have a bluetooth feature but an explanation for that is given in the video.