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ADVANCED OPERATION - Splicing program structure: Splicing process
Attenuator making
Pre-defined program: 08
A typical splicing sequence for the attenuator making process
Attenuator making is the
process you use when you
want to reduce the strength
of a signal – because of a
short distance between a
transmitter and receiver, for
example. This signal
strength reduction is, for
most cases, achieved by
using RTC to measure and
set a cladding offset (see
diagram) to the desired
attenuation value. When the
targeted attenuation value is
reached, the fibers are
spliced.
FXUUHQW
ILEHUGLVWDQFH
gap
PDNHDJDSWR
UHPRYHK\VWHUHVLV
SUHKHDWEHIRUH
ILEHUWRXFK
WDNHZDUPLPDJH
WLPH
overlap
current 1
current 3
current 2
WDNHDZDUPLPDJHDQG
FRPSXWHWKHFODGGLQJRIIVHW
UHSHDWLIFODGGLQJRIIVHWLV
ELJJHUWKHQWDUJHW
RIIVHW
WXUQRIIDUFLIFODGGLQJ
RIIVHWRU WDUJHWRIIVHW
RUWKHF\FOHQXPEHU
UHDFKHVWKHF\FOHOLPLW
Attenuator making control parameters
ECF FACTOR
when set at a value between
1 and 10, compensates for
the surface tension men-
tioned in relation to hot core
alignment that bends the
cores out of alignment. If, on
the other hand, it is set to 0,
RTC is disabled, and if set
above 10 it determines the
limit to the number of RTC
cycles the splicer will carry
out before ending the splic-
ing sequence automatically
(see above diagram).
OFFSET ADJUSTMENT
is the means by which you
can adjust the target offset
(the intended offset after the
splicing sequence). The
value you enter here will be
added to the target offset
calculated by the splicer. To
make the value negative, you
should use the button.
DESIRED ATTENUAT.
is measured in dB, and
quantifies the desired attenu-
ation--the degree to which
you want to reduce signal
strength. If you select a
value greater than 0 dB, as
well as, give the mode field
diameters for each of the
fibers in the parameters LEFT
MFD and RIGHT MFD, the
splicer will automatically set
a target offset for the desired
attenuation.
-
take a cold image and
compute the cladding offset:
repeat if cladding offset is
bigger than target offset
Note:
For fibers with highly eccentric cores it is essential that the fibers are spliced with respect
to the position of the cores to get a good result. To achieve this, you need to increase the
parameter FUSION CURRENT 3 to 12 mA from its initial setting of 9mA. This will trigger
the attentator making process to take hot instead of cold images during the RTC proce-
dure, thereby making it possible to locate the cores.