Matrix switches, sometimes called crosspoint switches or crossbar switches, are a special category of switches that allow many different inputs to be routed independently to any of a number of outputs. Each input can go to one output or be split to multiple outputs simultaneously.

Video matrix switches, as the name implies, switch video signals between several sources (such as cameras, computers, DVD players, and cable boxes) and displays (monitors, TVs, or projectors). This type of switch is in use almost anywhere multiple video feeds are shown – auditoriums, trade shows, military command centers, airport terminals, sports bars, security surveillance control rooms, etc.

There are many different video signal formats – composite video, S-video, YPbPr component video, VGA, etc. – that are not directly compatible with each other. While there are some very expensive matrix switches on the market today that use proprietary modules to translate between these different formats, most customer applications use only a single format and do not require this added complexity and cost. A well-designed, inexpensive matrix switch that supports multiple video formats, but will not convert them is a cost-effective yet versatile solution for switching inputs and outputs with the same video format.

For more extensive installations requiring a large number of inputs and outputs, keeping all of the sources and displays in close proximity to the switch becomes less practical. The most common and cost-efficient method of long distance video transmission is over twisted pair cable, such as CAT5. In this configuration a specialized video extender is connected to each video source, which transmits the video (and optionally audio and other signals) up to 1000’ away. Likewise, a mating receiver is connected at every display device to reconvert the signal back into a standard format. Using a compatible video matrix switch in between, the components of the system can be spread out and tailored to the installation site.

There are several advantages for using a switch with CAT5 cable over coaxial cable, like RG-6: the cable itself is less expensive; it is thinner and more flexible, which is easier to install; and the jacks for the modular RJ45 connectors can be more tightly spaced, reducing the necessary enclosure height for a given size matrix switch.

Network Technologies Inc’s newest VEEMUX® Audio/Video Matrix Switch, the SM-16Xn-C5AV-1000, is designed to route A/V signals distributed by NTI’s 600’ and 1000’ video extenders. The switch allows connections from any transmitter unit to any receiver unit of compatible type. When used with NTI’s latest EDID-capable extenders, it can also transfer plug-and-play information about the display device to the transmitter unit from a single receiver unit, a composite of multiple receiver units, or a default value table.

This latest addition to the VEEMUX family is available in matrix sizes of 16x16, 16x32, 16x48, and 16x64. Of the 16 inputs, one port (port 16) is also capable of using a direct VGA and stereo audio local connection, selectable via DIP switch. For every bank of 16 outputs, one port (ports 16, 32, 48, and 64) splits its signal to a local VGA and stereo audio output. As a result of an innovative design, each NTI switch uses the least amount of rack space for its matrix size compared to other switches in the industry, saving cost when rack space is at a premium. For example, NTI’s largest switch, the 16x64, is only 3RU, while the other switches on the market with the same number of inputs and outputs are as large as 16RU.

The SM-16Xn-C5AV-1000 matrix switch can be controlled from the front panel keypad, optional infrared remote control, RS232 port, 10/100 Ethernet port, or USB console port. The front panel has a backlit LCD, which allows the user to see switch connections, system settings, and a digital VU-meter for audio level (right and left channels) of the currently selected port. A built-in web server provides a graphical interface for port switching, settings, and DDC information accessible from any connected computer’s browser.

NTI’s VEEMUX SM-16Xn-C5AV-1000 is a cost-effective and space-saving video matrix switch that will prove to be invaluable in most installations requiring a large number of inputs and outputs with long distance video transmission.