KRAMER ELECTRONICS LTD
2
1 INTRODUCTION
Congratulations on your purchase of this Kramer Electronics fiber optic interface. Since 1981 Kramer has been
dedicated to the development and manufacture of high quality video/audio equipment. The Kramer line has
become an integral part of many of the best production and presentation facilities around the world. In recent
years, Kramer has redesigned and upgraded most of the line, making the best even better. Kramer’s line of
professional video/audio electronics is one of the most versatile and complete available, and is a true leader in
terms of quality, workmanship, price/performance ratio and innovation. In addition to the Kramer line of high
quality switchers, such as the one you have just purchased, Kramer also offers a full line of high quality
distribution amplifiers, processors, interfaces, controllers and computer-related products. This manual includes
configuration, operation and option information for the following products from the Kramer line of fiber optic
interfaces. The machines described in this manual are listed below:
611T
– Fiber optic video transmitter
611R
– Fiber optic video receiver
1.1 A Word on Fiber Optics
In many studio applications, signals are transmitted from one location to another. The standard way to transmit
signals, whether video or audio is by using coaxial cables. This is an appropriate way when the distance
between the transmitter and receiver does not exceed several tens of meters, depending on signal bandwidth and
cable quality. Quality deterioration is inevitable, but in most studio applications, where standard, short-distance
cabling is used, it is acceptable.
In order to overcome signal losses in long distance applications, several solutions are available - namely, line
amplifiers which allow at least doubling of the operation distance, or a twisted pair system.
A twisted pair system uses different types of cables and special interface units, extending the effective range up
to 1km or so. With a good quality system, broadcast level signals can be handled over hundreds of meters.
The problem of quality signal transmission and reception becomes serious when signals have to travel distances
of several kilometers. In this case, neither the line amplifier solution nor the twisted-pair solution is appropriate.
A good option for high quality signal transmission over several kilometers distance is the fiber optic solution.
This system uses a ray of light travelling in a tiny optic fiber carrying the signals. The transmitting device
converts the electric signal (video or audio) into the form of a modulated light signal. The modulated light
signal (usually red or infrared) is forwarded to a special connector that couples the modulated light signal to the
optic fiber.
The receiver is connected to the other side of the fiber, which is equipped with appropriate connectors (there are
several different types of connectors used for fiber optic signal transmission systems). The receiver reconverts
the ray of modulated light back to an electric signal, which is a copy of the original signal introduced to the
transmitter.
The
611T/611R
uses the fiber optic Multi-Mode system, which has a range of up to 5 km. Thick optic fibers are
used, which are easy to manufacture and to install.