Agilent Technologies 35670-90066 manual Set the oscilloscope to 700 mV/div

Agilent 35670A	Troubleshooting the Analyzer
	To troubleshoot input and ADC failures

Step 2. Check the dc offset DAC.

• Using the BNC-to-SMB cable, connect the oscilloscope to A1 P200 to check channel 1 or to A1 P700 to check channel 2.

G	If you changed the input signal or range, set the input signal to 2 Vp-p and the
	range to 1 Vpk.
	• Set the oscilloscope to 700 mV/div.
	• Press the following keys:
	[ System Utility ]
	[ MORE ]
	[ SERVICE TESTS ]
	[ SPCL TEST MODES ]
	[ MORE SPCL MODES ]
	[ CHANNEL 1 SPCL MODE ] or [ CHANNEL 2 SPCL MODE ]
	[ OFFSET DAC ]
	0
	[ ENTER ]

•Note the dc offset voltage of the sine wave displayed on the oscilloscope.

•Enter numbers between 127 and +128.

The sine wave dc offset voltage should change about 780 mV for a −127 entry and −780 mV for a +127 entry.

•If the dc offset function is incorrect, the A1 Input assembly is probably faulty.

•If the dc offset function is correct, the A5 Analog assembly is probably faulty.

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