The signal required the color to be selected at high speeds "on the fly" as the beam was being drawn across the screen.

During the encounter, signals from the spacecraft required 246 minutes to reach the Earth.

All those complex visual signals require a lot of processing power, far more than would be needed if just points were being processed.

A digital signal travelling a significant distance will become weaker and distorted and require periodic help to continue its journey successfully.

The signal requires the driver to stop in front of it.

Another problem with the RCA connectors is that each signal requires its own plug.

High-definition signals require a high-definition television or computer monitor in order to be viewed.

Interlaced signals require a display that is natively capable of showing the individual fields in a sequential order.

As the name implies this signal requires trains to move at Restricted speed, specifically with the ability to stop short of an obstruction.

Instead, the 1-bit signal is recorded directly and in theory only requires a lowpass filter to reconstruct the original analog waveform.