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521 East 3rd Street
Mount Vernon, NY 10553
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The Many Reasons to Upgrade your A/V Installation with CAT5
Posted on Monday, June 1, 2009


Masha Lakhter                     
Phone: 914-667-9700 ext. 211
Cell: 917-701-3238
Fax: 914-668-8666        
The Many Reasons to Upgrade your
A/V Installation with CAT5.
Mount Vernon, NY– Key Digital, Inc., the leader in video technology and solutions is de-mystifying the video distribution hurdle.
Category 5 cable, better know as CAT5, is a very popular and simple connection that can be used for every possible signal distribution throughout your installation. CAT5 cable and its variations, CAT5e, CAT6, and CAT7, are an inexpensive and functional solution that, with proper installation and the right technology, can make vast improvements in your A/V installation. Recent technological advancements, along with the many options available in the market, can make CAT5 usage tricky and mysterious for some, but for those in the know, it can take your installation to the next level.
Twisted pair is relatively simple to manufacture and since it’s widely used for all kinds of connectivity it is probably one of the least expensive cabling available today. Twisted pair was invented before the coaxial cable in the 1920’s, and was established as a default connectivity media for low bandwidth applications such as telephony and telegraph. However, with the invention of television and its increase in bandwidth consumption, coaxial cable quickly took over for TV applications because twisted pair has lower noise immunity and lower available bandwidth. The steady increase in twisted pair usage today for TV, HDTV and PC video connectivity is basically due to the availability in contemporary silicon processing capability at a reasonable price. These powerful silicon chips compensate for the deficiencies of the twisted pair very successfully, making CAT5 cable an option for home and business A/V installations.
Here are some of the key fundamentals that are involved in CAT cabling.
1. Video
The distribution of traditional RGBHV or Component Video, Audio, RS-232 and IR information has become easier and more accessible thanks to the this wonderful “twisted” media. In order to understand the benefits of CAT5, I will first address the technical aspects of how it works.
How does twisted pair work?
Diagram 1
This simple block diagram (Diagram 1) describes how the Balun (twisted pair) can deliver signal without noise. The needed signal is sent “differentially” (one of the wires in the twisted pair carries positive signal while the other is a negative, or inverted, signal). Mathematically, in the receiver end, these signals are subtracted from each other, and since they are inverted to each other in the first place, the subtraction process results in the output signal with double the amplitude:
S - (- S) = 2S
The noise added from the surrounding environment isn’t “differential”. The same subtraction on the receiving end thereby canceling any non-differential signaling such as noise that can be added to the cables:
N - N = 0
Fundamentally, due to the nature of twisted wires, CAT5 wire is an equivalent of many coils and capacitors that produces a Low Pass Filter, Diagram 2:
Diagram 2
The longer the CAT5 cable is, the more virtual coils and capacitors there are and the more severe the effects of the Low Pass Filtering. Thus, the longer the cabling, the lower the bandwidth will be, and since bandwidth is directly responsible for distance vs. resolution, the capability is greatly lowered, shown by red line (CAT5 Performance) in Diagram 3.

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