EDM 01-11v8 DAG 6.1S Card User Guide
©2005
8
Version 8: May 2006
3.1 DAG 6.1S Card Optical Power Input
, continued
Input power
The DAG 6.1S card is set up to measure the optical power at the receiver,
and to make sure that it is well within the specified power range of -9
dBm.
Input power is adjusted by:
•
Changing splitter ratio if power is too high or too low, or
•
Inserting an optical attenuator if power is too high.
3.2 Splitter Losses
Description
Splitters have the insertion losses marked on packaging or in
accompanying documentation.
•
A 50:50 splitter will have an insertion loss of between 3 dB and 4
dB on each output
•
90:10 splitter will have losses of about 10 dB in the high loss output,
and <2 dB in the low loss output
The GT10-RXU uses 1310nm optics. Splitters used must be designed for
1310nm as the insertion loss will vary for different wavelengths.
Single mode
fibre loss
A single mode fibre connected to a multi-mode input has minimal extra
loss.
Multi-mode
fibre loss
A multi-mode fibre connected to a single mode input creates large and
unpredictable loss.
