The variable attenuator
is ideal for simulating cable loss for lab testing of link power
margin or reducing power in links where receivers are being
overloaded. The variable attenuator is of the gap-loss type.
Pulling the connector end-faces apart induces the loss. Since
the light exists in an expanding cone, the receiving fiber will
capture less light, as the gap gets larger. An air gap
attenuator is ideal for use with any LED systems and many laser
systems. Some laser systems, especially high-speed digital links
(over 1 GB/s) or analog CATV systems may not operate well with
the attenuator due to back reflections; you should use the
ATT120 with a FC/APC connector, if you use an attenuator in
those types of systems. The variable attenuator fits to cables
with the connector type shown in the specification. If you need
to use the attenuator with other connector types, use hybrid
cables. The fiber type used should also match the network fiber
type, with one exception: if in a single mode network receivers
are used with a multimode “bucket” fiber, you can use a matching
multimode fiber on the receiver side of the attenuator. |