Simulate Changing the Channel on an Old-School Television with This Modified Set

The cathode ray tube television set

Invented in the early 20th century, cathode ray tube display technology was everywhere and used for activities such as watching TV, browsing the internet, and gaming. However, their large size and inefficiency led to their eventual demise, with the successor being LCDs. But before this, early versions of the CRT television included TV tuners that required a knob to be spun in order to pick up the current broadcast, where each station would be briefly interrupted by a blank static screen before becoming clear with the next image.

Changing the channel

Because TV broadcasts and television sets themselves are nearly 100% digital now, some people miss the nostalgia of changing the channel with a rotary dial and watching the static-filled transition. It was for this reason that television technology aficionado and YouTuber Rodrigo Feliciano decided to recreate the old-school style of display by constructing a Raspberry Pi TV simulator. His idea was to take an existing five-inch television set from from mid-twentieth century and replace its internals with a Raspberry Pi 3B and Arduino Pro Mini, which would feed in new video and show the classic black-and-white transitional static.

A few modifications

Luckily for Feliciano, the TV set he selected already had support for either 12V, AC, and even battery power, which made converting the 12V DC input into 5v that the Raspberry Pi 3B and Arduino Pro Mini could use easy via a regulator module. At the back of the unit are a pair of analog input plugs for composite video and audio, while the current input is selected with a switch. Because the static needed to be authentic and not just some video, Feliciano made some minor adjustments to the TV's main board that included routing the analog video/audio inputs through a relay board and isolating the tuning potentiometer so that the Arduino Mini Pro could read its value.

Showing video

The code for this project running on the Arduino board simply reads the tuning potentiometer via an analog input pin and selects the correct channel according to the value. If the dial is in the process of being turned, then it switches the relay to show the random static of the video input jack rather than the video that the Raspberry Pi is outputting.

All of the electronic components were also able to conveniently fit inside the TV's battery compartment for improved cleanliness/portability.

Future improvements

Currently, the simulator works quite well in its intended role, although Feliciano does note some possible improvements that could be made in the near-future. Because of the way the Pi plays videos, the terminal or even the mouse cursor can be accidentally seen, which can be detrimental to the viewing experience. He also hopes to track where each movie was left off so it can be resumed rather than starting from the beginning.