HP 8340B Manual page 31

4-5. MAXIMUM LEVELED OUTPUT POWER AND POWER ACCURACY
TEST (Cont'd)
The maximum leveled power indication may differ with sweep mode and
sweep time. To find the worst case, the maximum leveled power is
checked in continuous sweep with auto sweep time (step 3), single
sweep with auto sweep time (step 4), and single sweep with a two
second sweep time (step 5).
Press [SINGLESWEEP] repeatedly and
4.
S. Press [SWEEPTIME] and enter [2] [sec]. Repeat step 3.
6. Select the mode that gave the worst case maximum leveled power indication (lowest ENTRY
DISPLAY indication). Press [M2] and use the rotary knob to position the marker to the minimum
power level point on the oscilloscope trace (for a negative polarity crystal detector, this is the
highest point on the display, for a positive polarity detector, this is the lowest point on the display).
Using the oscilloscope vertical position control, position the marker on a horizontal graticule line.
Note the marker frequency. Press [MANUAL] a nd enter the frequency noted for M2. Due to SYTM
tracking, the RF output level at a single frequency may be greater than in a swept mode. therefore,
if the oscilloscope now indicates a higher power level than the swept response (for a positive
polarity detector, the trace moves down), press [POWERLEVEL] and (using the rotary knob)
adjust the power level to return the dot on the oscilloscope to the horizontal reference line for the
minimum swept power point.
7. Disconnect the 10 dB pad and crystal detector and connect the Power Sensor to the DUT RF
output. Set the Power Meter's calibration factor switch to include the frequency noted for M2.
To obtain the most accurate Power Meter reading, zero the Power Meter on the range being used.
To zero the Power Meter, press the Power Meter RANGE HOLD, press DUT [RF] off, zero the
Power Meter, and press [RF] on.
The Power Meter indication should be equal to or greater than the maximum leveled power
specification. If the DUT does not meet its maximum leveled power specification, refer to SRD
Bias and SYTM Tracking adjustments in Section V.
8. Press the[START FREQ] key and enter the start frequency for the next band. Press the [STOP
FREQUENCY] key and enter the stop frequency for the next band. Repeat steps 3 through 7 until
all frequency bands have been checked.
FLATN ESS
9. Flatness is measured with the RF output level at 0 dBm. Flatness is primarily a function of the RF
path; therefore, the response will be essentially the same at all ALC levels. Although the ALC
accuracy is not specified separately, the ALC accuracy is typically <0.15 dB for RF output levels
from +10 dBm to —9.9S dBm.
To test ALC accuracy, step the DUTs RF power in 1 dB steps from +10 to —9.95 dBm (note, for
instruments with front panel RF output, that as the power steps from —9.9S to —10 dBm, the RF
attenuator is set to 10 dB and the ALC is set to 0 dBm). If the power meter indication is >0.1S dB
from the ENTRY DISPLAY indication, refer to the ALC adjustments in Section V (in the Service
Manual).
HP 8340B/41B
NOTE
repeat step 3.
Performance Tests 4-29