Promax US TV EXPLORER II, User Manual

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USER’S MANUAL. US TV EXPLORER II
Page 52 01/2008
On the screen appears the deviation peaks in order to observe if they are within a
suitable range limit valid for both, the receiver and the transmitter in the transmitting
system.
5.14.4 Analogue FM: Measuring the Level and demodulating signal
Press the Measurement Configuration [17] key to accede to the
CONFIGURATION menu and turn the rotary selector [1] in order to select the analogue
FM signal. In the analogue FM measurement mode, the US TV EXPLORER II display
works like an analogue level indicator showing the signal level present in the input.
FREQ:
CH: » LEVEL:
FM DEV: 56.6
53
dBµV
kHz MHz 103.80
10 30 50 70 90 110 130
Figure 27.- FM analogue signal measurement
The instrument also demodule the FM carrier (radio) and allows to listen sound
through the loudspeaker [33].
5.14.5 Analogue/Digital TV: Measuring the Carrier / Noise ratio (C/N)
The US TV EXPLORER II carries out C/N ratio measurement in four different
ways, according to the carrier type and the used band:
A) Terrestrial band, analogue carrier
Carrier level is measured using a quasi-peak detector (230 kHz BW). Noise level
is measured with an average detector and corrected to refer it to channel
equivalent noise bandwidth (according to the definition of the selected standard).
B) Terrestrial band, digital carrier
Both measurements are done with an average detector (230 kHz) and the same
corrections are introduced on them (bandwidth corrections).