Guralp Systems CMG-DM16R8, Operating Manual

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CMG-DM16
duplex link, over which the digitizer can be remotely
configured. To monitor the digitizer’s output locally, connect a
laptop PC to the Monitor connector and run SCREAM. To
configure the digitizer locally, connect the laptop PC to the
front Monitor connector using a specially-wired (pin 4 to pin 1;
see pinouts) 9-way male serial plug. Use of the specially-wired
plug temporarily disables the rear Data connector, and
converts the front Monitor connector to duplex, allowing
digitizer configuration and monitoring.
Analog Inputs : Analog inputs (+/- 10Vdc) can be connected
to the digitizer via the front BNC connectors or via the rear 25-
way connector (see pinouts attached).
Terminate unused input ports on the front panel with a 50 Ω
BNC terminator cap,
unless the 25 way rear connector is used
for signal inputs into the digitizer. If you use the 25-way
connector for an input, then the corresponding BNC input on
the front must not be terminated.
GPS Receiver : Use the cable provided to connect the GPS
receiver (Garmin antenna) to the rear GPS In connector. The
DM16/R8 is designed to allow a single GPS receiver to
synchronize multiple digitizers. The first digitizer in the chain
must have the GPS receiver connected directly to the rear GPS
In connector. Subsequent digitizers can be daisy-chained
together, using the rear GPS Out and GPS In connectors. Note
that each digitizer in the line adds 5.5 microseconds delay to
the actual GPS time stamp.
6 Issue C