Keysight NFA Series Noise Figure Analyzers Service Guide 409
Assembly Replacement Procedures
RF Area (N8976B)
RF Area (N8976B)
Refer to Figure 15-15. The RF area consists of RF attenuator A (1), RF 
attenuator B (2), low band switch assembly (3), and YTF Preselector (4). 
Figure 15-15  RF Area Components and Cables - N8976B