Chapter 2 157
Performance Verification Tests
21. Resolution Bandwidth Accuracy
21. Resolution Bandwidth Accuracy
The output of a synthesized signal generator is connected to the Input
of the analyzer, characterized through a 1 dB step attenuator set to
3 dB. The amplitude of the synthesized signal generator is set to a
reference amplitude 5 dB below the top of the screen. A marker
reference is set and the attenuator is set to 0 dB.
The markers of the analyzer are then used to measure the 3 dB
bandwidth. The first marker is set on the left filter skirt so that the
marker delta amplitude is 1 dB plus the attenuator error for the 3 dB
setting. The second marker is similarly set on the right filter skirt. The
frequency difference between the two markers is the 3 dB bandwidth.
Resolution bandwidth settings £300 Hz (Option 1DR) are not
measured. These bandwidths are digitally derived; therefore, their
accuracy is verified by design.
The related adjustment for this performance test is “IF Amplitude.”
Equipment Required
Synthesized signal generator
Cable, BNC, 122-cm (48-in)
Cable, Type-N, 152-cm (60-in) (2 required)
1 dB step attenuator
Attenuator/switch driver (if programmable step attenuators are
used)
Additional Equipment for 75 Ω Input
Pad, minimum loss
Adapter, Type-N (f), to BNC (m), 75 Ω
Additional Equipment for Option BAB
Adapter, Type-N (f), to APC 3.5 (f)