Me in my TV head costume. I'm wearing an old computer monitor on my head, with a cute bow on the front.

In Fall 2020, I got an old broken CRT monitor from my college's recycling cage and turned it into a helmet with a working RGB LED display. Here's some information about how I made it and how it works. If you want to make a TV head without the electronics, this method should still work if you ignore all the electronic parts. If you just want to see the finished costume, skip to the gallery.

Non-electronics

I disassembled the CRT monitor, being careful to discharge the cathode to avoid a painful electric shock. (I think my monitor was self-discharging anyway, but it's a good idea to be sure.) I put the big glass cathode ray tube away in a cardboard box so I wouldn't accidentally trip over it and make it implode, which would be unpleasant for multiple reasons. I cleaned out the inside of the monitor and shook out the dead ladybugs that had collected inside over the years. I eventually used a dremel to cut a hole in the bottom of the monitor just big enough to fit my head through.

My first prototype used plexiglass for the screen, but I found that a thinner sheet of polycarbonate was much lighter on my neck and flexible enough to bend into a convex shape, which makes the helmet look more realistic. I tinted the polycarbonate using some privacy window film.

The most difficult and frustrating part of this project was getting the helmet to fit comfortably using upholstery foam. Other guides on the internet show that they just use three blocks of foam cut into rectangles that you cram your head between, but that was unacceptable for me. I eventually figured out a good foam setup that leaves my ears uncovered, which is nice because it lets me hear and wear my glasses.

I hot glued everything together. I eventually added posable telescopic antennae extracted from an old TV antenna from a thrift store.

Electronics

The screen is made of 300 individually-addressable RGB LEDs, specifically WS2812Bs. I made the LED matrix from a single 5-meter, 60 LEDs/meter strip by cutting it into 15 strips of 20 pixels each and soldering them together. People often ask me how I can see through the helmet; the answer is that I designed the matrix to have empty space between the strips:

The opened helmet, showing the foam and matrix.

It's like wearing sunglasses and slotted shades at the same time, so visibility is pretty good in a well-lit area, but bad enough in the dark that I need someone to hold my hand when I walk down unlit streets on Halloween night.

A Circuit Playground Express microcontroller (similar to an Arduino) controls the lights using a program I wrote. A mini PS/2 keyboard connects to the microcontroller through an adapter for an input method. This lets me control the lights. Just a few buttons would suffice for playing animations, but I opted for a full keyboard so I can type words to appear on the screen. The microcontroller has a built-in accelerometer which I use for a few gravity-sensitive animations.

Here's a circuit diagram of the whole thing.

A circuit diagram. It depicts a Circuit Playground Express microcontroller powered by a USB power bank, receiving data from a PS/2 keyboard through a PS/2 to UART converter, and sending data through a level shifter into the LED matrix.

TV Head Mk. 2

In 2021, I collaborated with my friend Ellie to make them a TV head like mine, but better! The improvements were largely motivated by an added goal: Ellie wanted to display Chinese text on the screen. Chinese glyphs are more complicated than ASCII so we needed a resolution at least as big as mine despite the screen being smaller than mine.

The issue was that you can only make LED strips so dense before you need to make them wider, too. 60 LEDs/meter seems to be the densest you can go without sacrificing strip narrowness. We cleverly worked around this by laying the strips diagonally across the screen rather than laterally! This resulted in a tighter grid of 24x18 resolution. We also used extra-narrow LED strips, which gives Ellie more room to see between them, at the cost of more light reflecting back into their face instead of getting blocked by the margins of the strips.

This video shows the front panel detached, so you can see how the strips are arranged. Here's a photo of the back of the panel if you want to see the wiring.

The requirement of Chinese text also motivated a better input method. You can type Chinese on an English keyboard if you have a GUI, but it's hard without one. So, we used a Circuit Playground Bluefruit to control the helmet wirelessly from a phone, which is way easier than using a keyboard.

For some reason, the Circuit Playground Bluefruit cannot control more than about 200 LEDs. I don't know if it's a hardware limitation or a fault with the FastLED library. We were running out of time to finish the helmet, so we fixed this by using two Circuit Playgrounds: a Circuit Playground Bluefruit to communicate with the phone, and a Circuit Playground Express to control the LEDs. It's a goofy bodge but it works; a better solution would be to use something like a Bluefruit LE UART Friend in place of the Circuit Playground Bluefruit. It basically takes the place of the PS/2 to UART converter in the circuit diagram.

Advice

Here are some lessons I learned and tips to anyone who might want to try making one of these.

Make sure you get LED strips with black PCB, so they aren't visible through the tint.
You can buy clips to attach ws2812 strips to each other without soldering, but beware! They might give an unreliable data pin connection, which can cause the matrix to glitch out and strobe.
Of course, don't make your animations strobe on purpose either, or you might give someone a seizure.
To conserve battery life and lower current requirements, try minimizing the amount of light your animations use. Program brightness adjustment too.
Don't get hot glue in your hair.
The level shifter apparently wasn't necessary. The whole thing worked perfectly even when I accidentally used 3.3V everywhere instead of 5V, even the USB keyboard!
Try to keep the helmet light so you don't strain your neck. Put the battery in the back to counterweight the screen.
Cover logos on the monitor with something that gives it personality. In my case, the cute bow works well.
I recommend using Bluetooth connected to your phone rather than a hardware keyboard, like I did for the Mk. 2! Replace the PS/2 to UART converter with something like a Bluefruit LE UART Friend.
Don't buy the LED strips from Adafruit, you can get them way cheaper elsewhere. Aliexpress is probably the cheapest if you're willing to wait for long shipping times.
I had never soldered before making this project, but I learned how, and you probably can too!

If you're trying to make your own TV head, feel free to ask me for advice! Send me a message on Discord (vivian#9409) or Mastodon or Twitter, or email me at [my first name]@[this domain]. If you don't need my advice, contact me anyway when you finish your TV head so you can show it to me!

Acknowledgements

Thanks to Franci Bolden for helping me with the dremel and bandsaw, and for insightful advice that I wouldn't have thought of! Also thanks to fuchsia and Izzy Swart for early hardware advice!

Gallery

Blurry photo of Ellie in their helmet in the dark with hands raised, looking like a cryptid.

Here's a video demonstrating the animations. The lights look small in this video because I had the brightness turned down.

Here's a promotional video of us made by Marietta College video producer Mary Roberts.

Also check out this gallery of TV heads others have made using this writeup!