Keysight N8976B

Keysight NFA Series Noise Figure Analyzers Service Guide 231
Front End Control Troubleshooting
A15 Front End Control Description
Standard RF Assemblies Controlled by the A15:
— A9 Input Attenuator A (4 dB total for the N8973B, 74B, and 75B, 10 dB total
for the N8976B)
— A10 Input Attenuator B (66 dB total for the N8973B, 74B, and 75B, 60 dB
total for the N8976B)
— A11 Low Band Switch
— A12 YIG Tuned Filter
— A13 RF Front End Assembly
A15 On Board Circuits:
— RF Burst Trigger (When set to Relative Trigger or when center frequency is
< 300 MHz.)
— YTF Tune Ramp
— Preselector Tune Out (Provides output voltage, not specified, reserved for
future use)
—Mixer Bias
—Amplifier Bias
—Switch Control
— Sweep Ramp (reserved for future use)