Keysight NFA Series Noise Figure Analyzers Service Guide 275
L.O. Synthesizer/Reference Troubleshooting
A14 L.O. Synthesizer Troubleshooting
— Verify the 4800 MHz input signal from the A16 Reference Assembly is stable 
by pressing FREQ, Span, 50 kHz, BW, 1 kHz. The signal on the functioning 
spectrum analyzer should be very stable both in frequency and power as 
shown in Figure 8-4.
— Reconnect the W6 cable to A14J200.
Figure 8-4  4800 MHz Narrow Span
If the 4800 MHz signal is not measuring the correct power level, see the 
“A16 Reference Assembly Troubleshooting” section later in this chapter.