5-15.
ALC ADJUSTMENTS (Cont’d)
ADJUST AM OFFSET
27. Connect the Power Sensor to the OUT’s
RF
OUTPUT. Press [INSTRPRESET]. Press [CW] and
enter [1]
[GHz].
The power level should be 0 dBm. Disconnect any AM inputs. Access Calibration
Constant Number 43 by
entering the following: [SHIFT][GHz][4] [3] [Hz] [SHIFT][MHz] [1] [2]
[Hz] [SHIFT][kHz] [2] [2]
[Hz].
Adjust Calibration Constant Number 43 for no more than 0.05 dB
change in power meter indication when turning AM on then off.
AM GAIN ADJUSTMENT
28. Set up the following equipment as shown in Figure 5-50 with the power supply set to 0 Vdc. Allow
the equipment to warm up for at least 30 minutes.
DUT
POWER METER
ADAPTER
APC—3.5(f)
to N(m)
Figure 5-50.
AM GAINAdjustment Test Setup
29. Calibrate the power meter and then set the calibration factor switch for a 1.5 GHz measurement.
Connect the power sensor to the
OUT’s RF output.
30. Press the following key sequence on the OUT:
[INSTRPRESET]
[CW] [1]
[.]
[5] [GHz]
[POWERLEVEL] [—] [5] [dBm]
[AM].
31. Adjust the power supply for 0 Vdc. Press dB [REF]on the power meter (the power meter will now
indicate the power level changes from this reference).
BNC
TEE
5-98
Adjustments
HP 8340B/41B