GENERAL INFORMATION
The Pure Digital Fiberlink
®
7220 Series is a transmitter/receiver pair
that transmits a single channel of RGBHV video and two audio chan-
nels over one single mode or multimode fiber. It is available as a free-
standing box unit or as a card version for use in the rackmountable
6000A card cage.
The system’s all digital encoding delivers noise-free transmissions
that retain all of their initial parameters, regardless of fiber optic cable
attenuation. System operation may be easily monitored using integral
indicator LEDs on each unit that continuously signify the presence of
baseband video and audio signals.
Introduction
Technical Specifications
Model Part Number Configurations:
Unit Type
Part Number
Transmitter Box
7220-B7S
Transmitter Rack Card
7220-C7S
Receiver Box
7221-B7S
Receiver Rack Card
7221-C7S
All units transmit at
1310 nm wavelength
over single mode or
multimode fiber. ST
connectors are
provided.
Video:
Input Impedance ....................... RGB: 75 Ohms; H&V: Hi-Z
Input Level ............................... RGB: 714 mV p-p; H&V: 3 to 5 V p-p
H Sync Frequency Range ......... 31.5 to 60 kHz
V Sync Frequency Range ......... 30 to 85 Hz
Number of Video Channels ...... 1 RGBHV
RGB Format Supported ............ RGB with separate H and V
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MAINTENANCE AND REPAIRS
The Pure Digital Fiberlink
®
7220 Series transmission units have been
manufactured using the latest semiconductor devices and techniques
that electronic technology has to offer. They have been designed for
long, reliable and trouble-free service and are not normally field repair-
able. Should difficulty be encountered, Communications Specialties
maintains a complete service facility to render accurate, timely and re-
liable service of all products.
The only maintenance that can be provided by the user is to ascertain
that the optical connectors are free of dust or dirt that could interfere
with light transmission and that electrical connections are secure and
accurate. DANGER!
Always disconnect the transmitter power before
removing the optical fiber from the unit!
All other questions or comments should be directed to our Customer
Service Department. It should be noted that many “problems” can eas-
ily be solved by a simple phone call.
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The status of the VIDEO and AUDIO indicator LEDs should provide
the first clue as to the origin of an operational failure. If these are off, it
usually means that the fiber is broken or has too much attenuation. Next,
be certain that the input and output signal connections are correct.
Finally, although multimode and single mode devices may look the
same, they will not operate properly together. Using the wrong device
or fiber can easily add more attenuation than specified, resulting in poor
overall performance.
If, after reviewing the above possibilities, the system is still not oper-
ating, please contact the Customer Service Department for further as-
sistance.
