Kingfisher KI 025 Series, Operating & Maintenance Manual

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KI 025 UM-5
5
Introduction
The KI 025 Series Optical Talk Set is designed to provide convenient
full duplex voice communication on one optical fibre.
The superb optical performance of the 1550 nm Laser version covers
all normal applications on singlemode or multimode fibre, enabling
long and short haul applications to be solved with a single model.
Other units are available, covering all possible wavelengths and
applications up to 200 kms.
Reliable field operation is guaranteed by a unique combination of
features such as very simple to operate controls, rugged drop proof
construction and reliable analogue transmission.
Conferencing of 3 or 4 units may be achieved by using the dual
output ports.
The dual optical port is fully drop protected, and can be cleaned
easily in the field.
High quality duplex voice transmission is maintained over the full
optical range, with no operator intervention. An optical reserve of
typical 5 dB allows intelligible operation over very poor joints for
emergency use.
The hands-free 'speakerphone' is convenient for most users, and this
automatically changes to headset operation when the headset is
plugged in. For noisy situations, or intermittent use, a manual
transmit mode is available.
In any mode, a buzzer can be used to call the remote unit. The
same buzzer can be used as a 2 KHz source for fibre identifiers.
Limits of Operation
This optical talk-set uses a sophisticated receiver arrangement to
provide operation over a very broad range of optical power, thus
giving the user great flexibility without the need to make adjustments.
If you have an optical attenuator available, try testing the audio
performance over a wide range of optical attenuation settings, eg. up
to 50 dB or more.
As the limits of performance are reached, the background noise will
become louder, and eventually the sound will fade altogether.
Note also that at very high loss levels, the set tends towards
half-duplex operation, and you will find that you will have to use the
headset, as the speakerphone will not operate properly.
Most users will find that the set operates well on both singlemode
and multimode fibres; however the greatest optical loss range will
apply to the correct fibre type.
Typical losses of a multimode-singlemode mismatch are around
10~13 dB, depending of fibre types and the mode field.
Other Kingfisher products include optical attenuators, return loss test
sets, light sources and power meter instruments.