AP301-FULL-HD_rev.09_UK
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4.6.4.
SYNCH PULSE
On the left side of the screen, on measurement mode the horizontal synch pulse appears,
as in an oscilloscope. Very important information may be obtained by watching this
indication, especially in terrestrial band. For instance, a pulse reduction indicates a start of
compression of the switchboard’s final amplifier, whereas a reduction or increase of burst
indicates a wrong calibration of the amplifier of the considered channel.
4.6.5.
DCP DIGITAL CHANNEL POWER
Also power measurement can be carried out, by integrating the power of the whole digital
channel. To start measuring, keep the
MEA
key pressed and select DCP INTEGRAL function
from the menu. The instrument makes measurement inside the channel with central
frequency corresponding to tuning frequency and channel bandwidth previously set. The
outcome is displayed on the menu line.
4.6.6.
CARRIER/NOISE RATIO MEASUREMENT
The instrument carries out the Carrier/Noise (C/N) ratio measurement in several ways,
depending on terrestrial or satellite band and analogue or digital signal. In order to measure
noise, the carrier should be off; since this is not possible, a close frequency without other
signals is selected.
Measurement can be started from MEASURE mode as follows: press the
MENU
key, select
C/N
turning the shaft encoder and press
ENTER
to confirm.
Measurement is carried out automatically or manually according to the selection in MEA
menu, C/N PRMT submenu. In case of previous manual setting, it is necessary to select the
NOISE frequency after recalling the measure. The instrument makes the best-point search
easier through panoramic mode. After setting the NOISE frequency, press
ENTER
to
complete measurement.
4.6.7.
SATELLITE VIDEO POLARITY
The polarity of a video signal of analogue satellite transmissions can be positive or negative.
This generally depends on the reception band, Ku or C. Polarity is selected in the
TV
engaged menu, as described hereinafter.
4.6.8.
FULL-SCREEN TV PICTURE
To watch a tuned TV channel on full screen press the
TV
key. The signal is often better on
this mode than on measurement mode, because the instrument optimizes the input
attenuation and uses the tuner’s AGC. The instrument operates like a typical TV, allowing an
actual estimation of the response of installation.
4.6.9.
TV ENGAGED MENU
This menu is activated keeping the
TV
key pressed. Select the desired item turning the
shaft encoder and activate it pressing
ENTER
. Press
TV
to exit. The menu items are the
following:
