Maintaining Video Signal Quality in a Distribution System
When video distribution was over coax you had two choices: (1) use a tap-and-trunk system, calculate the correct tap value for the first drop, then the second drop, and so on. (2) use a home-run system that required you to either have outputs from the home-run matrix of splitters that were set up for long runs, medium runs and short runs, or the easy way out, was to use an attenuator at the drop to get the level you wanted. These types of distribution systems were cost-effective regarding the hardware, but took time to design and even more to implement and maintain.
Problems related to the coax systems have been around since cable TV distribution came into existence. Many times a bad TV signal could be identified by:
How long the distribution system had been in place?
Whether or not there had been adds, moves and changes made to the system since installation?
Was the system installed by professional RF installers or in-house personnel?
Were the amplifiers and taps suited for the frequency spectrum being distributed?
Were the coax “F” connector fittings tight at all terminations?
Was the slope and level of the incoming signal into the system measured and adjusted?
Was there any documentation as to the cabling infrastructure?
Then along come video distribution over Unshielded Twisted Pair/Category Cable (CAT 5 or CAT 6). There were a couple of passive component systems that worked well in moderately small environments with limited drops. Once these systems went beyond 50 or more TV drops on multiple floors, design and installation became more complicated. Here again the cost were relatively low for the equipment and components, but the time spent installing and balancing was labor intensive.
The next evolution was to have an active UTP distribution system that was plug-and-play. This is where Z-Band, Inc. set the standard. The only adjustment required for the entire Z-Band system was to ensure that the level and flatness of the signal coming into the master distribution hub meet the system’s specs. Once the correct broadband signal was fed into the Z-Band master hub (“GigaBUD”), the functionality of the system was self-adjusting. It becomes plug-and-play from the horizontal UTP cable output of the video hubs to the TV display devices. A remotely powered/intelligent balun (“GigaBOB”) is placed at the display device to ensure that the correct signal was constantly being fed into the TV.
Bottom line, a well designed system will function for years, but as technology changes so do the ways of getting a consistent, high quality video signal to every TV.