396 Chapter 2
Performance Verification Tests
54. Comms Frequency Response (Option BAC or BAH)
is being measured.
6. Set the source frequency to 50 MHz and amplitude to 0 dBm.
7. Adjust the source amplitude to obtain a Channel A power meter
reading of –10 dBm ±0.1 dB (if the preamp is not being tested), or a
power meter reading of –20 dBm ±0.1 dB (if the preamp is being
tested).
8. Record the source amplitude setting, and both the Channel A and
Channel B power meter readings in Table 2-108.
9. Tune the source to the next frequency in Table 2-108.
10.On the power meter, set the Channel A calibration factor to the
calibration factor of the reference sensor for the current source
frequency.
11.Adjust the source amplitude to obtain a Channel A power meter
reading of –10 dBm ±0.1 dB (if the preamp is not being tested), or a
power meter reading of –20 dBm ±0.1 dB (if the preamp is being
tested).
12.Record the source amplitude setting, and both the Channel A and
Channel B power meter readings in Table 2-108. If the preamp is
being measured, enter these values in the “Preamp On” columns.
Otherwise, enter these values in the “Preamp Off” columns.
13.Repeat step 9 through step 12 for frequencies up to 2000 MHz in
Table 2-108.
14.For each entry in Table 2-108, calculate the splitter tracking error as
follows:
For example, if Channel A Power is –10.05 dBm and Channel B
Power is –10.23 dBm, the Splitter Tracking Error is 0.18 dB.
NOTE When calculating the splitter tracking error with the 20 dB fixed
attenuator in place, the splitter tracking errors will be nominally 20 dB.
Splitter Tracking Error Channel A Power Channel B Power–=
Table 2-108 Source/Splitter Characterization
Frequency
Power Meter Reading Splitter Tracking
Error Source Power
Setting
Channel A Channel B
Preamp
Off
Preamp
On
Preamp
Off
Preamp
On
Preamp
Off
Preamp
On
Preamp
Off
Preamp
On
50 MHz
800 MHz