Tektronix 071-0590-00 user manual Change the Prbs pattern type

Tutorial

5.Change the PRBS pattern type

These steps demonstrate one of the many benefits of our Full-Featured Auto- Search algorithm - automatic synchronization to the incoming signal by selecting the correct PRBS test pattern.

A.Locate the controls in the PATTERN box of the Generator. Make sure the

PRBS button is enabled (the LED inside this switch should be ON). Set the Generator pattern to a 27 PRBS as follows:

Set this parameter	…to this value	…using this procedure.
PRBS type	PN 7	Press pattern up/down arrow keys until
		PATTERN is set to PN 7

As the PRBS pattern type is changed, the Analyzer will start searching for a match. You should see the BIT, PHASE, and SYNC LOSS LED’s turn ON in the Error History section of the Analyzer. While the Analyzer is searching for the correct PRBS type, the LOCK LED in the Error Detection Section should turn OFF. When synchronization is achieved, the LOCK LED should turn ON.

B.Locate the controls in the ERROR DETECTION box of the Analyzer. Zero all Analyzer error counts by pressing the CLEAR key.

C.Locate the controls in the ERROR HISTORY box of the Analyzer. Reset all Analyzer history LEDs by pressing this CLEAR key. Confirm that all ERROR HISTORY LED’s are turned OFF.

D.Locate the controls in the ERROR INJECT box of the Generator. Press the ERROR INJECT SINGLE key several times. Verify that the error count displayed by the Analyzer increments each time the Generator SINGLE key is pressed. Verify the BIT LED light located in the Error History Section of the Analyzer turns on.

6.Turn off AUTO - SEARCH and change Generator Outputs

These steps demonstrate one of the many benefits of our Full-Featured Auto- Search algorithm - setting the input data decision voltage to its optimum value. While the Auto-Search feature is disabled, the Generator output voltage will be adjusted to cause loss of sync. Auto-Search will then be enabled to correct this synchronization problem.

A.Locate the controls in the SYNC box of the Analyzer. Disable the AUTO SEARCH function by pressing the AUTO SEARCH key. The amber LED within this switch will be OFF when the Analyzer AUTO SEARCH function is DISABLED. If the LED is ON, press the AUTO SEARCH function one time to turn the LED OFF.

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