Nautel VS300, Руководство по предварительной установке, Страница: 46 / 62

VS300 Pre-installation Manual Planning for control and monitoring
Page 8-8 Issue 2.0 2010-12-01
RF monitor sample
A true RF sample of the RF output voltage waveform is available for external monitoring on the
RF
MONITOR
BNC connector (J2) on the rear panel of the transmitter. Figure 8.3 shows the frequency
response of the RF monitor sample’s coupler. The coupler yields approximately -39dB (± 1.5 dB),
relative to the carrier level, at the FM broadcast carrier frequency (88 - 108 MHz). Note that there is a
“boost” in the coupler response at higher order (harmonic) frequencies. This boost can be up to +15
to +20 dB relative to the carrier frequency. Subtract the boost value - determined from
Figure 8.3 -
from any harmonic measurements made from this sample port. NOTE: there is a 1 to 2 dB tolerance
on the boost values.
Figure 8.3: RF Monitor Sample Frequency Response
150 300 450
600
750
900
1050
1200
1350
1500
Freq (MHz)