How to convert coaxial cable to HDMI

Updated February 21, 2017

Coaxial cable carries audio and video signals from a television programming source to a TV. Modern television sets, especially high definition TVs, are equipped with different jacks for connecting to a source. The most common digital connection is a High Definition Media Interface (HDMI) cable that uses a six-sided plug. Converting coaxial cable to HDMI requires a powered adaptor similar to an old RF modulator for converting coaxial signals. Available at electronics stores, the adaptor attaches to both cables in minutes.

Connect the coaxial cable to the signal adaptor box by attaching the cable coupler to the threaded jack on the box and turning clockwise by hand.

Connect the other end of the coaxial cable to a compatible signal source, such as the receiver box for cable or satellite TV.

Plug an HDMI cable into the adaptor box with the wider end of the cable turned upward. An HDMI plug inserts in one direction only.

Connect the other end of the HDMI cable to a port on the back of a TV, monitor or other video device, again with the wider end of the plug turned upward. If the TV or monitor has more than one HDMI Input, make a note of which one is used with the coaxial cable connection.

Plug the adaptor and the TV into a surge protector power strip, which can then be connected to a wall outlet.


Press the "Input" button on the TV remote repeatedly until the signal from the coaxial cable appears on screen.


Do not connect the adaptor or the TV to the electricity until the cable connections are complete.

Things You'll Need

  • Coaxial cable
  • Coax to HDMI adaptor
  • HDMI cable
Cite this Article A tool to create a citation to reference this article Cite this Article

About the Author

James Clark began his career in 1985. He has written about electronics, appliance repair and outdoor topics for a variety of publications and websites. He has more than four years of experience in appliance and electrical repairs. Clark holds a bachelor's degree in political science.