Scale Fidelity - Keysight N8973B Service Manual

Functional Tests

Scale Fidelity

Scale Fidelity
Test Limits
The scale fidelity error will be ≤ ±1.0 dB with ≤ -10 dBm at the mixer.
This test checks the scale fidelity of the instrument by maintaining a constant
reference level and measuring signals of different amplitudes over most of the
display range. This test sets the input attenuator to 10 dB and the Reference
Level to 0 dBm. The external attenuator is set to 0 dB, and the amplitude of the
source is adjusted to set the displayed signal at the reference level.
The instrument's internal marker is used to measure the reference amplitude.
The Marker Delta function is activated and the RF input is reduced using the
external precision step attenuator. Signal input levels from 0 dBm to -50 dBm
are measured.
Item
Adapter,
a
Type-N (m), to 3.5 mm (f)
Adapter,
a
3.5 mm (f) to 3.5 mm (f)
Adapter,
2.4 mm (f) to 3.5 mm (f)
b
(2 required)
Attenuator, 10 dB Step
Attenuator, 10 dB fixed (2 required)
Cable, 3.5 mm, 1 meter (2 required)
Cable, BNC 120 cm
Synthesized Sweeper
a. For N8973B, 74B, 75B
b. For N8976B
514
Critical Specifications
(for this test)
Frequency: 50 MHz
VSWR: < 1.1:1
Frequency: 50 MHz
VSWR: < 1.1:1
Frequency: 50 MHz
VSWR: < 1.1:1
Range: 0-50 dB
Frequency: 50 MHz
Accuracy: ±0.25 dB
Frequency: 50 MHz
VSWR: < 1.2:1
Frequency: 50 MHz
VSWR: < 1.4:1
Frequency: 10 MHz
Output Level Accuracy: 0 to –15 dBm: ±1.0 dB at 50 MHz
Keysight NFA Series Noise Figure Analyzers Service Guide
Recommended
Keysight Model
1250-1745
83059B
11901B
8495A
8493C, Option 010
11500E
10503A
PSG