Introduction: Make an Old TV Into an 80s Themed Clock

About: I am a hobbyist with an interest in open-source software, 3D printing, science and electronics. Please visit my store or Patreon page to help support my work!

This Instructable shows how you can turn any TV or monitor into an animated 80s themed clock with "melting" digits!

From the Atari color palette, to the use of an analog composite video signal, everything about this clock screams retro! Even the melting digits have quite a bit of history behind them, being first conceived by Steve Capps, a designer of the original Apple Macintosh, in 1976 (the year I was born!). As a kid, I came across a version of this clock for the Mac Plus and I have loved the visual style ever since!

I made my first version for the Arduino several years ago, but this one is an improvement in many ways!

  • Uses the way more powerful ESP32 microcontroller
  • Fewer components and much easier to put together
  • Improved visual design and details
  • Four different color themes!
  • Web based configuration
  • Network time synchronization

A Warning About CRT Burn-In

It was well known in the 80s and 90s that leaving a unchanging image on a CRT would eventually lead to burn-in, which would cause a permanent mark on the screen. This clock displays a fairly static image which will almost certainly cause some degree of burn-in over time. While you can delay the effect by reducing the image brightness, you should be aware that using this clock 24/7 will eventually cause irreversible marking of the display. So I do not recommend you use this on a CRT you want to keep pristine! To avoid this problem, you can consider using an LCD panel with a composite input instead of a vintage CRT.


Step 1: Download the Source Code

  1. Visit the GitHub page for the esp32-dali-clock source code
  2. Click on the green "Code" button, then "Download ZIP"
  3. Uncompress the zip file to your hard disk someplace

Step 2: Connect the ESP32 to Your TV or Monitor

  1. Use an alligator clip to connect the pin labeled "GND" on the Adafruit HUZZAH32 to the outside barrel of the RCA plug
  2. Use an alligator clip to connect the pin labeled "A1/DAC1" on the Adafruit HUZZAH32 to the central pin of the RCA plug
  3. Connect the other end of the RCA cable to the yellow jack on your TV or monitor

Step 3: Get and Configure the Arduino IDE

  1. Download the Arduino IDE from the Arduino web page.
  2. Select "File -> Preferences" and type "" into the "Additional Boards Manager URLs"
  3. Hit "Okay"
  4. Select "Tools -> Board: (xxxxxxx) -> Boards Manager..."
  5. Type "ESP32" in the search bar
  6. Select the latest version from the dropdown and click "Install"
  7. Once the installation is over, click "Close" to quit the Boards Manager

Step 4: Compile and Upload the Sketch

  1. From the Arduino IDE, select "File -> Open..." and find the "esp32-dali-clock.ino" inside the source code folder you unpacked earlier
  2. Select "Tools -> Board (xxxxx) -> ESP32 Arduino -> Adafruit ESP32 Feather"
  3. Plug in the ESP32 Feather to your computer using a micro USB cable
  4. Select "Tools -> Port" and select the serial port for your board
  5. If your TV only supports the PAL standard, skip ahead to step 7, make the changes, then return here.
  6. Select "Sketch -> Upload"

Step 5: Configure the Dali Clock Via WiFi

At this point, you should see the clock on your display, but the time will be incorrect.

Using your phone or computer, connect to the wireless point called "ESP32 Dali Clock". This will take you to a configuration webpage.

At this point, enter the information for your wireless network in the "Network Name" and "Network Password" fields. Also select your time zone and whether your location is observing Daylight Saving Time. Click "Submit" to complete the configuration and reboot the board.

Watch the screen for status information as the ESP32 connects to the network. If you need to reconfigure the clock, you will need to use the web address that is indicated on the screen.

Step 6: Selecting the Color Scheme

You can use the "Color Theme" drop down menu to select one of the following choices:

  • Time-of-Day Blend: The colors will gradually change throughout the day, giving a visual indication of time of dat.
  • Minute Blend: Cycle through all the color variations in a minute, for demonstration purposes.
  • Night Theme Only: Always use the night color scheme
  • Dawn Theme Only: Always use the dawn color scheme
  • Day Theme Only: Always use the day color scheme
  • Dusk Theme Only: Always use the dusk color scheme

Step 7: Optional: Changing the Color Mode to PAL

If you are using a TV that only supports the PAL standard, such as might be the case if you live in Europe, you will need to change a few lines of code prior to uploading the sketch, as indicated in the picture.

Step 8: Optional: Triggering the Calendar Display

Add two additional wires to the pins labeled A5/4 and A4/36. If you touch the end of the wires with your finger, it will trigger the display of the calendar date momentarily.

Retro Tech Challenge

Second Prize in the
Retro Tech Challenge