On the 12 Days of Christmas, an EE Gave to Me…

December 25, 2020 by Hannah DeTavis

In this electrical engineering edition of the 12 days of Christmas, we take a look at a few familiar highlights of the season and zoom in on the technologies electrical engineers have contributed to make them possible.

2020 took its toll on the electrical engineering community just as it did on many other disciplines across the globe.

Beyond the incredible feats of EEs this year—banding together to meet the global ventilator shortage, devising rapid COVID-19 testing devices, and increasing safety in public spaces—engineers have contributed in creative ways to keeping our lives afloat amidst worldwide shutdowns. 


Emergency MIT ventilator

MIT's emergency ventilator project. Image used courtesy of MIT

During this Christmas season, the editorial staff wants to thank the All About Circuits community for the many projects you’ve worked on over the years to help us all feel a little closer in an age of social distancing. 

In this electrical engineering edition of the 12 days of Christmas, we take a look at a few familiar highlights of the season and zoom in on the technologies EEs have contributed to make them possible.

Without further ado… 

On the 12 days of Christmas, an EE gave to me:


12 Feet of LEDs

Gone are the days of checking bulbs one by one to find the culprit in a string of lights gone dark. LED Christmas lights are less susceptible to catastrophic decoration failure than old-fashioned incandescent versions. 


LED lights

Image used courtesy of Michael Hession and The New York Times

11 Laser Lights

Laser-projected Christmas lights are an easy way to cheer up your home during the holiday. Unlike traditional Christmas lights that require a bulb, laser projectors can create sharp patterns of red and green light. 


10 Hallmark Movies

Love them or hate them, Hallmark movies are best viewed on an LCD flat screen. This technology switches pixels on or off electronically using liquid crystals to rotate the polarization of light, presenting a vibrant picture of however many formulaic rom-coms you can stomach. 


9 Ham Radios

Amateur radio is a great way to get involved in community events (managing comms for a Christmas 5K anyone?), prepare for natural disasters, or chat with other hams. Yes, the functionality of antennas extends much further than ham radios nowadays, as we discuss in the fundamentals of Wi-Fi antennas, but there's something about a ham radio that touches the tinkerer in all of us.


Ham transceiver

A look inside the Baofeng amateur radio transceiver. 

(See AAC's contributor Mark Hughes tear down a Baofeng amateur radio transceiver to see what we mean!) 


8 Smartphone Gadgets

The holidays are a great time to gift a loved one with a new smartphone or its many accompanying gadgets. EEs have made several notable innovations in these accessories, from noise-canceling headphones to wireless chargers


7 Music Speakers

As romantic as it sounds to blare Bing Crosby over an old-fashioned phonograph, most of us enjoy holiday music with the help of modern mixed-signal audio systems


Diagram of a standard three-way speaker system

Diagram of a standard three-way speaker system, including a tweeter, a midrange speaker, and a woofer. Image (adapted) used courtesy of Georgia State University

Sound quality wouldn’t be so “merry and bright,” though, without attention to detail at the circuit level as we’ve discussed in many technical articles on digital signal processing, Class-D amplifiers, and operational amplifiers, among others.

6 Webcam Calls

With a global pandemic waging on, many people have found themselves relying on video calls not only for work communication but also to keep in touch with loved ones from afar. Thanks to EEs’ prowess with CMOS image sensors and audio devices such as MEMS microphones, we can still see the faces of friends and family via webcam. 


5 PS5s

While many electronic designs have sentimental value, others are just plain fun. The PS5 is one of the most hyped Christmas gifts of the year, and from what we know about it, some savvy engineering went into all the bells and whistles. 

Just last month, Sony released a teardown video describing the hardware ins and outs of “the most transformative console yet.” 


Sony's Yasuhiro Ootori disassembles a PS5 as he chats through the hardware of the new console

Sony's Yasuhiro Ootori disassembles a PS5 as he chats through the hardware of the new console. Screenshot used courtesy of Sony

4 Space Heaters

If you’ve been dreaming of a white Christmas, it might be time to break out a good old space heater. If yours has been gathering dust, you might check out one of our past teardowns on space heaters to help you get it started again. 


3 E-Secure Credit Cards

Those holiday purchases with your credit card are etched with silicon security, leveraging the capabilities of universal integrated circuit cards (UICCs) and near-field communication (NFC)


General structure of NFC data transmission

General structure of NFC data transmission. Image used courtesy of Rohde & Schwarz

On the flip side, credit card readers might not be as simplistic as they seem at face value. We also have a teardown that picks apart the inner circuitry of these devices.


2 Christmas Train Sets

Maybe it’s one of the first gadgets you took apart as a kid or maybe you’d like to tinker with a broken electronic train set before it begins its journey around the Christmas tree. This hobbyist shows how he disassembled a Christmas train set from the thrift store to repair the light, sound, and smoke effects.


1 Amazing AAC Community

From robust forum discussions to insightful comments on educational content, the editorial team thanks you for your ongoing participation on All About Circuits. Your voice helps us better serve novice and practicing electrical engineers alike. 

Wishing you and yours a very happy holiday season! 

1 Comment
  • H
    hafcanadian January 01, 2021

    I’m not so sure about the LED Xmas light revolution.  My 20 twelve-lamp C9 “In Motion” control-moduled outdoor sets drive me nuts.  With 4 wires emanating from each lamp it can be a nightmare of confusion trying to sort out what’s wrong.  The lamps don’t go out, but rather go to white in groups of 3 or 4, or all 12.  Then the next time they are powered up they can be okay… or go all white mid-evening.  It’s easy to suspect the control module on each set, but usually if I juggle lamps I can get it working again.  Too often it’s been a bad 4-wire RGB lamp, but finding that one is a bugger;  it’s not like the simpler 2-wire lamps at all.

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