Tektronix WVR5250, Installation And Safety Instructions

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Basic installation procedure
Line termination Your instrument uses a passive loop-through reference input, so the loop-through
input must be terminated externally. It is important that this external termination
meets accuracy and return loss requirements.
If the instrument is installed to monitor an operating link, the destination receiver
and the connecting cable serve as the termination. This monitoring connection
checks the performance of the entire path. The return loss of the instrument is
suf
fi ciently high that, in most cases, the destination receiver sets the system return
loss.
In cases where the instrument is placed at the end of a link, a BNC termination
must be installed on one side of the loop-through reference connector. The
termination must be 75
Ω and DC coupled (good return loss extends to DC). An
appropriate termination for the EXT REF connector is Tektronix part number
011-0163-00; this is a 75
Ω , End-of-Line termination.
Compatibility of BNC
center pins
Most BNC connectors for video equipment, whether 50 Ω or 75 Ω , use a 50 Ω
standard center pin. Some laboratory 75 Ω BNC connectors use a smaller
diameter center pin. The BNC connectors on the instrument are designed to work
with the 50
Ω standard (large diameter) center pins.
Do not use connectors or terminators with the smaller center pins. They could
cause intermittent connections.
18 WVR5250 Installation and Safety Instructions