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Keysight N774-C & 8162-C Series User’s Guide
2
Getting Started
For the complete list of adapters, refer to the chapter
Analog Output
The analog output is the BNC connector on the back of the optical head. It
outputs a voltage directly proportional to the strength of the optical signal
at the optical input in the current range. The analog signal is always in the
range between 0 and 2 V, 2 V corresponding to a full power input signal in
the current range, 0 V corresponding to no input signal.
During autoranging, the level to which 2 V corresponds changes. You
should disable autoranging when using the analog output.
Applications
Possible applications for the analog output are:
• to close the feedback loop controlling the current supplied to a laser
• to aid positioning the system for fiber alignment tasks
• to monitor optical power on an oscilloscope
The analog signal reacts instantaneously to the input signal.
Optical Input
The optical input to the optical head requires a connector adapter to
match the connector type (or bare fiber) to the optical head interface.
The optical head interface can be either threaded or a D-type magnetic
interface depending on the model of optical head (81628C is only available
with a threaded interface). For the complete list of adapters, refer to the
chapter
When a connector adapter is fitted it should be locked in place by
tightening the locking screws located either side of the main optical head
housing.
NOTE
All optical Heads (except the 81628C) are shipped including a mounted
81624DD adapter ring. To use D-type magnetic connector adapters, this
ring should be removed by loosening the locking screws shown in
with a 1.5 mm hex key.