How can you provide TV service to hundreds of TVs in a building that only has Cat 5 cable installed? One solution is to use RF baluns to convert the coax signals to balanced signals that travel on twisted pair cable.

IPTV is also an option, but the equipment can be expensive and bandwidth requirements are substantial - about 4 Mbps for digital channels and 15 Mbps for HD channels. In commercial applications where lots of TVs are watching lots of different channels, the aggregate bandwidth can exceed the capabilities of the data network.

An RF balun system makes it possible to deliver hundreds of digital channels on twisted pair cable, without using any bandwidth on the network. For example, the Lynx Television Network manufactured by Lynx Broadband delivers 288 channels of digital television over distances up to 295 feet (90 meters) or 78 analog channels over the same distance. For applications using the full 860 MHz CATV spectrum,

the performance capabilities are 528 digital channels or 134 analog channels over 220 feet.
Lynx networks are installed in more than 50 U.S. hospitals and hotels, including the Sheraton Hotel at the Baltimore Washington Airport. The hotel did not install coax because it planned to use a streaming video delivery system. But shortly before opening they encountered technical and availability issues. Installing the Lynx product let them open on time, with full television service available in all the guest rooms.

According to Dale Sennie, the network engineer for the hotel management company, the total cost of the satellite TV headend and all the Lynx equipment was only $40,000 (approximately $200 per room for the 203 room installation).

The diagram below shows how the television signals are transported through the hotel. A cabling closet is strategically located in the

Figure 2. Dale Sennie with Lynx Video Hubs in a Wiring Closet

Source Lynx Broadband

Figure 4 Wallplate Connector Source Lynx Broadand

middle of each of the hotel's three floors and is easily within cabling transmission distances to guest rooms on each floor.

Hubs and Converters

A sixteen port hub in the wiring closet converts two coax input signals into sixteen Cat 5 output signals. More specifically, sixteen RF baluns inside the hubs convert the unbalanced 75 ohm coaxial signals into 100 ohm balanced signals that travel on pair four of the Cat 5 cable.

At the point of use, a Decora style wallplate connector (shown below) converts the balanced Cat 5 signal back to an unbalanced coaxial signal that is delivered to the TV. A wallplate cover then goes over the connector.

Benefits of RF balun technology

Because RF baluns do not use any bandwidth on the network itself, they eliminate quality of service problems that could develop when of IPTV and data delivery compete for limited bandwidth on the datacom network. They are also less expensive than most IPTV delivery systems.

The technology also has several advantages relative to coax. It is much more flexible for handling moves, adds, and changes, and it is usually less expensive in retrofit applications.

Equally important, it is more reliable than coax because it's tap and drop design eliminates the taps and splitters located behind walls and above ceilings in traditional "tap and drop" coax systems. Fewer taps and splitters means fewer connectors and thus fewer problems.

Finally, using RF baluns creates a "technology bridge" to IPTV. It is inevitable that IPTV will become less expensive and less bandwidth intensive over time. So it is only prudent to "future proof" the building by having twisted pair cable connected to all the TVs.

GREGG KELLEY is National Sales & Marketing Manager for Lynx Broadband in Burnsville, MN. He can be reached at www.lynxbroadband.com.

Lynx Broadband is a division of BH Electronics, which manufactures high frequency electro-magnetic components for the electronics and telecommunications industries. BH Electronics was founded in 1967 and has manufacturing capabilities in Minnesota, Mexico, and China. See www.lynxbroadband.com for more information.

Figure 3 16 Port Hub. Source Lynx Broadband