Anritsu BERTWave MP2100B, Operation Manual, Page: 143 / 382

5.4 Setting Reference Clock
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5
Generating Pulse Signal
5.4 Setting Reference Clock
The PPG uses the reference clock to generate the data.
The reference clock can be selected from the following supply sources:
 Internal clock generated inside the BERTWave
 External clock input from the Ext Clk In connector
 External clock input from the External 10 MHz Input connector
The internal clock accuracy is ±10 ppm after power is applied for 1 hour.
The external clock is used under the following conditions:
 When synchronizing other equipment with clock
 When using clock with higher accuracy than internal clock
The Ext Clk In connector is an AC coupling.
1/16 clock frequency range displayed in the bit rate specifications
[Variable] is input to Ext Clk In connector.
The bit rate of the signal output from the BERTWave is calculated by the
following formula.
R f Br
EXT
  
16
Br: Bit rate (kbit/s)
f
EXT
: Clock frequency (kHz) input to the Ext Clk In connector
R: Divide Ratio (1/1, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64)
Example: When setting the bit rate to 9953280 kbit/s, input the clock
frequency (622080 kHz) and set the divide ratio to 1/1.
The External 10 MHz Input connector is a DC coupling.
The 10 MHz clock of the sine wave or short waveform is input to the
External 10MHz Input connector.
With the Options 012 and 014, the reference clock can be set separately
for channels 1 and 2.
Table 5.4-1 Reference CLK Settings
Reference CLK Description
Internal 10MHz Use the internal clock based on the internal 10 MHz
transmitter
Ext 10MHz In Use the external clock input from the External 10 MHz Input
connector
Ext 1/16 In Use the external clock input from the Ext Clk In connector
Ch1 (Only available for Ch2) Use the clock synchronized with the
Ch1 clock
Note:
Always touch [Apply] if using the external clock.