Tektronix 071-0590-00 Data signal not detected. Selected, Threshold is below the minimum level

Tutorial

Set DATA	Verify these results on the Analyzer	Comments
THRESHOLD
to this value

	Press the ERROR DETECTION and ERROR	Data signal not detected. Selected
-0.50 volts	HISTORY “CLEAR KEYS”, then confirm:	threshold is below the minimum level of
	SYNC LOSS and BIT LED’s are ON	your data signal.
	SYNC LOCK LED is OFF
	ERROR RATE display shows “NO
	DATA” or a 50% Error Rate.
	Press the ERROR DETECTION and ERROR	You are starting to detect the data signal.
Approximately	HISTORY “CLEAR KEYS”, then confirm:	Selected threshold is near the minimum
		level of your data signal. Data threshold
-0.30 volts	SYNC LOSS should turn OFF
		is NOT CORRECT and you should expect
to	BIT and PHASE LED’s should turn ON	BER errors.
-0.25 volts
	SYNC LOCK LED should turn ON
	Press the ERROR DETECTION and ERROR	Data signal fully detected. Selected
+0.00 volts	HISTORY “CLEAR KEYS”, then confirm:	threshold is at an optimum value for the
	SYNC LOSS should turn OFF	input data signal. This is typically =
		1/2*[max level - min level].
	BIT and PHASE LED’s should turn OFF	Signal levels detected above this
	SYNC LOCK LED should turn ON	threshold are considered a logical “1”
		and signal levels below this threshold are
	ERROR RATE display shows NO BER	considered a logical “0”.
	ERRORS equivalent to a rate of
	0.0E-9 or better.
	Press the ERROR DETECTION and ERROR	Data signal not detected. Selected
+1.00 volts	HISTORY “CLEAR KEYS”, then confirm:	threshold is above the maximum level of
	SYNC LOSS and BIT LED’s are ON	your data signal.
	SYNC LOCK LED is OFF
	ERROR RATE display shows “NO
	DATA” or a 50% Error Rate

2-36 GB1400 User Manual