how do cat6 patch panel Piggyback works ?

One commonly used solution to cable-length limitations is something called HDMI over Cat 6. ­Steven D’Addone, co-owner of Intra Home Systems in New Jersey, an installer of high-end audiovisual systems, swears by the technology. “We only run cat6 patch panel,” he says.
Here’s how it works: A video source, such as an HD cable box, is connected to a small device­­—a “balun,” in the parlance of the trade—with a short HDMI cable. The balun usually takes the form of a small, router-like box or a wall plate. Its job is to pass the HDMI signal along to one or more cat5e cable or Cat 6 cables. (These are the same cables used to wire Ethernet networks—Cat 5e is a more common cable, but the ­newer Cat 6 standard is preferred by AV installers for its higher bandwidth.) At the receiving end, a similar box passes the signal back onto an hdmi wall plate, which then connects to your display.
Now, all HDMI over cat6 patch panel baluns are not created equal. Some crudely bridge the HDMI and cat6 patch cables by relying on the signal power of the original video source—this limits the range considerably. Others compress and then decompress the HDMI signal, but this can cause hardware compatibility problems. D’Addone recommends a third type of system. “What seems to be the most reliable are products that are high-­bandwidth and powered on both sides,” he says. These boxes, which can be found for about $100 each, create a direct bridge between HDMI and a pair of Cat 6 cables, but provide extra power to ensure the signal can travel distances up to 150 feet.
Best of all, powered HDMI over Cat 6 preserves the quality of video and audio ­signals. And given the low cable price—about a dollar per 10 feet online—HDMI over Cat 6 makes the most economic sense for longer throws.