Agilent Technologies E4438C - Manual (Page 66)

Performance Tests
Residual FM (Not Used with Option UNJ or Option 506)
3-18
Residual FM
(Not Used with Option UNJ or Option 506)
This automated test verifies the residual frequency modulation (FM) specification. The signal generator’s RF
output signal is mixed with a signal from a low noise external LO. The resultant IF signal is demodulated as
it passes through the measuring receiver, bypassing the measuring receiver’s internal mixer which is
inherently more noisy. Then the audio analyzer measures the demodulated audio signal for an RMS voltage.
The measurement is scaled and displayed as RMS mV, but read as residual FM in Hz.
Recommended Equipment
• Agilent 8902A measuring receiver
• Agilent 8903B audio analyzer with Options 010 and 051, or Options 011 and 050
• Agilent 8662A/8663A high-performance RF signal generator
• MD/MDC-164 mixer (0.5 to 9 GHz)
• MD/MDC-174 mixer (1.0 to 2.8 GHz)
Equipment Setups
Figure 3-16 Residual FM
(Not Used with Option UNJ or Option 506)
≤
2500 MHz Setup