Agilent Technologies 8360 L Series, Service Manual

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Adjustment Help
The follo wing explanations are pro vided for a b etter understanding of the amplier/multiplier
adjustmen ts. Refer to these explanations as often as necessary . They will help make these
adjustmen ts easier. (The adjustmen t pro cedure follo ws.)
Offset and Gain Adjustments.
F or all oset and gain adjustmen ts, adjust thr ough the bandpass. Keep adjusting un til the
p o w er p eaks and then drops o. Then reset the adjustmen t to the p eak ed p oint.
F or all oset and gain adjustmen ts, if p o w er stays p eak ed o v er sev eral calibration constan t
v alues, set the calibration constan t to the middle v alue of the p eak ed range.
Adjusting to the Center of the P assband.
The amplier/multiplier has a tracking lter on its output. Its purp ose is to pass the
selected RF output frequency and reject harmonics. The ob jective of this pro cedure is to
track the bandpass lter with the RF output frequency o v er a v ariety of sw eep conditions
and frequency ranges. Eects of the auxiliary output may mask the true cen ter of the
bandpass. Alwa ys tune to the low er p eak (lo w er calibration constan t v alue).
SRD Bias Adjustment.
Adjust these calibration constan ts into sque gging and then bac k o un til p eak p o w er is
ac hiev ed.
After reac hing p eak p o w er, decrease the calibration constan t v alue b y 15 coun ts when
adjusting the A term and decrease p o w er b y 1/2 dB (approximately 1/3 division) when
adjusting the B term.
Single Band Delay Compensation Adjustments.
If a drop in p o w er greater than 1 division o ccurs when in single sw eep, increase the A
dela y term to put the A term at the high end of the p eak. F or example, for the following
calibration constan t v alues:
Start of the p eak = 1800
Middle of the p eak = 1950
End of the p eak = 2100
Set the A term to 2050
Setting the F astest Sw eep Time.
Setting the sw eep time to 0 milliseconds sets the syn thesizer to the fastest sw eep time for
the frequency range b eing sw ept. Eac h time the frequency range is c hanged, the sw eep time
m ust b e reset to 0 ms in order to maintain the fastest sw eep time.
Sw eep Speed Related Adjustments.
Delay comp ensation adjustmen ts are aected b y sw eep sp eed. The adjustmen ts are
p erformed at fast sw eep sp eeds whic h are the w orst case.
All other adjustmen ts are p erformed at slow sw eep sp eeds; they are not aected b y sw eep
sp eed.
If y ou ha v e a p o w er problem that o ccurs only for fast sw eep rates, it is probably aected b y
dela y comp ensation or risetime adjustmen ts.
Agilent 8360 Adjustments
Amplifier/Multiplier Adjustments
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