HP (Hewlett-Packard) HP MPEGscope Startup Guide Printer User Manual


 
2-11
Getting Started
Connecting an External Clock Source
Connecting an External Clock Source
You can use an external clock to synchronize the MPEGscope transmitter to the
network. You can also use a 27 MHz external clock as an analysis reference for the
Realtime Analyzer.
The EXT CLK IN SMB connector accepts a 1 V pp unbalanced signal input,
terminating with 50 ohms. The 27 MHZ REF CLK SMB connector accepts a TTL
input. It has low impedance to ground when the unit is turned off.
Note For optimum performance, the total length of the external clock cable should not
exceed three meters in length (approximately 10 feet).
Connect an external transmit clock
source to the SMB connector on the
SPI interface.
Note: MPEGscope is able to use
this external clock source
when transmitting from any
interface, not just the SPI
interface.
DVBSPI Tx DVBSPI Rx
Connect an external 27 MHz TTL
clock source to the SMB
connector on the Realtime
Analyzer.
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Sarnoff