5-15.
ALC ADJUSTMENTS (Cont’d)
15. Connect the equipment as shown in Figure 5-47. Calibrate and zero the power meter. Allow one
hour warmup time. Connect the power sensor to the OUT’s RF output. Press [INSTRPRESET]
on
the OUT. Press [CW] and enter [4]
[.]
[5] [GHz].Press the [RF] key to turn the RF OFF and zero
the power meter. To ensure that the power meter is properly zeroed, select “WATT” mode, and
press ZERO until the power meter indicates =0.02on the most sensitive range. Press [RF] to turn
the RF ON. Press [PEAK]to turn peaking on. Press [SHIFT] [PWRSWP] to decouple the RF
attenuator and ALC. Enter [0] [dBm].If the display does not indicate ATTEN=0 dB, press STEP
keys as necessary to select 0 dB attenuation.
POWER METER
DUT
ADAPTER
APC—3.5(
il
to APC—3.5(f)
(83408 ONLY)
Figure 5-47.
ALC Adjustment Test Setup
NOTE
When the power level is changed significantly, it may take as long as one
minute for the power meter indication to be accurate. After making a
power level change, wait until the power meter indication stabilizes
before making any adjustments.
16. Refer to Table 5-8 below, enter the appropriate OUT power level (ALC level) and check the power
meter indication. Check the indication at each power level and note the amount of error before
making any adjustments. If necessary, adjust the appropriate controls shown in the table to adjust
the power level to be within the test limit shown.
Adjustments are
iterative. Adjust in the following order:
0 dBm, —10 dBin, —20 dBm,
—10
dBm, 0 dBm, +10 dBm, +18 dBin, and +10 dBin.
When selecting a new power level, press [SHIFT][PWRSWP] [desiredpower level] [dBm].
See Figure 5-48 for more information that may help to reduce the number of iterations required.
For example, if the +18 dBm indication is 0.1 dB low (+17.9 dBm), adjust for 0.05 dB high
(+18.05 dBm). Then when the +10 is adjusted to +10 dBin, the +18 will move close to the correct
level.
ADAPTER
APC—3.5(f)
to NIm)
(83418 ONLY)
HP 8340B/41B
Adjustments
5-93
