Anritsu 682XXB, 683XXB manual Calibration DAC to provide the correct amount

	AM
CALIBRATION	CALIBRATION

NOTE

For 682X5B/683X5B models, the procedure for Linear AM and Log AM calibration must also be per- formed twice—once for frequencies of ￿2.2 GHz and once for frequencies of >2.2 GHz.

4. Using the K (male) to 2.4 mm (female) adapter,

	connect the Power Sensor to the RF OUTPUT of
	the 682XXB/683XXB.
	NOTE
	Before beginning this calibration proce-
	dure, always let the 682XXB/683XXB
	warm up for a minimum of one hour.
AM	The following procedure let you (1) adjust the AM
Calibration	Calibration DAC to provide the correct amount of
Procedure	AM in both linear (100%/V sensitivity) and log
	(25 dB/V sensitivity) modes of operation for frequen-
	cies of ￿2 GHz and >2 GHz, (2) calibrate the AM Me-
	ter circuit, (3) calibrate the AM Function Generator,
	and (4) store the results in non-volatile memory
	(EEPROM) on the A17 CPU PCB.
	NOTE
	For those instruments that contain a Down
	Converter, the procedure for Linear AM
	and Log AM calibration must be performed
	twice—once for frequencies ￿2 GHz and
	once for frequencies >2 GHz. Upon initial
	completion of each procedure, the program
	will automatically return you to the start to
	repeat the procedure.
	1. Set up the Function Generator as follows:
	a. Mode: EXT
	b. Signal: Square Wave
	2. Perform Linear AM calibration as follows:
	a. At the $ prompt on the PC screen, type:
	calterm 112 and press <ENTER>.
	b. Set the function generator output to 0.00 volts.
	When done, press any key on the keyboard to
	continue calibration.
	c. Now, set the function generator to output
	￿0.50 volts. Use the COMPL button on the
	function generator to toggle the output be-
	tween +0.50 volts and –0.50 volts.
	d. On the computer keyboard, use 1, 2 or 3 to in-
	crement and 8, 9 and 0 to decrement the value
	of the DAC’s setting to obtain a 9.54 dB differ-
	ence in the power meter’s reading when the
	function generator’s output is toggled.

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