Elektor Lab Notes 10: ESP32 Projects, RPi5 Insights, and Engineering in Aachen

Welcome back to Elektor Lab Notes! Every few weeks, our creative engineers and busy editors post a few lab notes and updates about new DIY electronics projects, industry news, and helpful engineering insights. Feel free to share your thoughts in the Discussion section at the bottom of this page. Share your own lab notes and let us know what you are working on in your lab!
 

C. J. Abate (Director, Content and Lab, Elektor)

• Lab Work in Aachen: Our team spent some quality time at the Lab in Aachen, Germany, in early October. Over the past few months, the engineering/content team has grown to comprise new engineers, including Saad Imtaiz, Jean-Francois Simon, and Roberto Armani. All of them participated in 10 days of engineering and team building. During our time in Aachen, we worked on the following and more: Raspberry Pi 5 analysis and projects, a live Elektor Lab Talk, product reviews and testing, and content planning for upcoming editions, as well as for 2024. 

 

• Espressif Guest-Edited Edition of Elektor: As you know, we will publish an Espressif guest-edited edition of Elektor Mag this December. (Previously, we published Sparkfun and Arduino guest-edited editions.) We are currently hard at work finalizing everything. You're sure to find it insightful and inspiring. The extra-thick edition will be packed with projects, tutorials, interviews, and more. In fact, we have so much great content, that we're preparing a thick bonus edition as well! Stay tuned!

   

---

Saad Imtiaz (Senior Engineer, Elektor)

• ESP32-Powered ChatGPT Interaction: I’ve started on a captivating project that merges AI and IoT. Using ESP32, users can prompt ChatGPT to generate Micropython code, which is then wirelessly deployed to another ESP32 device. This fusion of chatbots and embedded systems showcases the potential of modern technology.

 

• Article: Low-Volume PCB Design Tips and Tricks: I've shared some expertise in PCB design when manufacturing in low volume through an insightful article. Titled “Low-Volume PCB Design Tips and Tricks,” it offers essential guidance for designing printed circuit boards in cost-effective and precise ways, also showcases some interesting ways to make your SMD Based PCBs. The article is scheduled to appear in the November/December edition of Elektor mag.

 

• Industry Insights Through Interviews: I had the privilege of interviewing two industry luminaries: Alessandro Ranellucci (Arduino) and Paulus Schoutsen (CEO of Home Assistant). Their perspectives shed light on open-source hardware and smart home automation trends, providing valuable insights to our readers. The interviews are slated to appear in the upcoming Espressif guest-edited issue of Elektor Mag.

 

• Energy Monitoring System with ESP32: Currently, I'm working on an Energy Monitoring System utilizing the ESP32 and a microchip-based energy metering IC. This project has the capability of energy consumption monitoring in a cost-effective and precise way, with applications spanning homes and small businesses. 

---

Jean-François Simon (Engineer, Elektor)

• Trip to Elektor Lab in Aachen, Germany: In early October, I got the chance to work alongside the rest of the team in the lab. We had a blast — it was fantastic getting to know everyone. I’ve been diving into a variety of topics, doing some research on a particular project based on ESP32 that we’re going to publish soon, and also reviewing the Fnirsi FNB58 USB meter. We’ve been throwing around ideas and brainstorming on project concepts related to the upcoming Raspberry Pi 5 with the team as well. It’s just too bad I couldn’t stay for more than a few minutes during the Lab Talk we recorded on my last day there!

 

• Clever Zero-Crossing Detection Circuit: I was brainstorming ideas to make my own controller for a DIY transformer-based spot welder. Of course, this is a very popular topic, and it has been done many times, but as is often the case, the fun is also in the journey, not only in the destination! So I was looking for ideas to sync a microcontroller to the mains in order to count mains cycles accurately. The idea being to switch on and off the primary of a transformer on a cycle-by-cycle basis. I came across this neat circuit: Zero Crossing Detector (Dextrel) Maybe you’ll find it useful too!

 

• Readily Available RS-485 Wireless Links from China: During my research for various RF transceiver modules that could potentially become part of another project, I accidentally came across some ready-made RS-485 wireless modules from China. Of course, there are many modules available that are breakout boards, with the RF chip, an antenna connector and a 0.1” header to connect the module to your PCB. But I wasn’t aware that you could also buy this kind of complete products:

I won’t provide direct links as these are too volatile, and I don’t endorse any vendor or product in particular, but you can find these by searching for “RS485 wireless DIN” on Aliexpress for example. Have you used this kind of modules in the past? Let me know in the comments below!
 

• Chip of the Month: LM74610: I stumbled upon this intriguing chip. It’s a MOSFET driver that can be used in conjunction with an N-channel FET to emulate an ideal diode, i.e. with nearly zero voltage drop in the forward direction. Well, ideal diodes are not so uncommon; at the time of writing, Digikey has more than 300 ICs in stock for this very purpose. What intrigued me is that this particular model doesn't need to be connected to circuit ground! Thus, one could build (or buy) an ideal diode module, based on a LM74610 and an N-channel MOSFET, that has only two terminals, like a real diode. That could come in handy for some projects to reduce wiring clutter…

I’ll let you dig into the LM74610 datasheet to find out the cleverness that can make this work!
 

• Interesting Personal Website: Scott at https://swharden.com truly has a talent to document and share his electronic works. I found its content fascinating, and the layout and pictures are very professional. Recently, I really enjoyed reading about his experiences with microcontrollers and building frequency counters.

---

---

Roberto Armani (Senior Editor, Elektor)

• Espressif Special Guest Edition: This challenging task, that goes along with the preparation of the regular November-December edition of Elektor, required quite a bit of work and concentration, but with the excellent cooperation of the Espressif's engineers, specialists and managers, it went well. There is still much to be done, but I am confident that our readers will have a thoroughly captivating issue to read!

 

• Analysis of the energy meter project with my colleague Saad: One of the main projects in the special will be...(um... I don't want to anticipate too much and spoil...) something energy-related, and we have considered the aspects of galvanic separation of power supplies, protection from extra-voltages and safety of use; stay tuned to read more!

 

• 3–10 October, Week in Aachen! Finally, after a fair amount of smart-working time, we had a chance to all get together in Aachen, to work together and do team-building, as well as planning content for future editions of the magazine. I didn't miss the opportunity to get my hands on the Elektor Lab tools!

---

Jens Nickel (Editor-in-Chief, Elektor Magazine)

• Elektor LabTalk: The last installment of the Elektor LabTalk was extra fun, as my colleagues and talk partners Brian and Saad were sitting right next to me in our studio in Aachen. We talked about the Wireless edition (September/October) of Elektor, the Energy meter Saad is currently working on, and — of course — also the new Raspberry Pi 5 and its advantages. Saad was able to make first measurements. If you missed the LabTalk live, you can watch it here on our Elektor YouTube channel. 

 

• Remote Controlled Amplifiers: One of my private projects is independent mobile music speaker "stations", integrating each a good-sounding passive speaker, a very compact but powerful ready-made amplifier, a Li-Ion-based 36-Volts battery and 433-MHz-transceiver for the audio signal. If you have four speakers in the field (2 satellites and 2 subwoofers) it is not very handy to manually set the volume for all the stations. So I had the idea to replace the potentiometers of the amplifier modules by digital ones, controlled by ESP32 boards. Fortunate coincidence: One of the DJs I know is an electronics engineer with a very nice home lab. We will keep you posted.