![Ronde & Schwarz 1304.0004K03 User Manual Download Page 110](http://html1.mh-extra.com/html/ronde-and-schwarz/1304-0004k03/1304-0004k03_user-manual_1484987110.webp)
The Spectrum Application (RF Measurements)
R&S
®
FPL1000
110
User Manual 1178.3370.02 ─ 11
Figure 6-10: Measurement of the AM modulation depth
The modulation depth is displayed as "MDepth". The frequency of the AF signal can be
obtained from the frequency display of the delta marker.
Measuring AM-Modulated Signals
The R&S
FPL1000 rectifies the RF input signal (that is, removes the negative parts)
and displays it as a magnitude spectrum. The rectification also demodulates AM-modu-
lated signals. The AF voltage can be displayed in zero span if the modulation side-
bands fall within the resolution bandwidth.
Displaying the AF of an AM-modulated signal (Zero Span)
Figure 6-11: Test setup
Table 6-5: Signal generator settings (e.g. R&S SMW)
Frequency
128 MHz
Level
-30 dBm
Modulation
50 % AM, 1 kHz AF
1. Select [PRESET] to reset the instrument.
Measurements and Results