Promax PRODIG-5 Manual Del Usuario página 142

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The horizontal lines define the signal level, the broken lines being separated a
distance equals to 10 dB. The level of the top line (70 dBμV in previous figure), named
Reference Level, can be altered using the vertical cursors
range of 60 dBμV to 130 dBμV by steps of 10 dB (from 70 dBμV to 130 dBμV in satellite
band).
The signal level for each frequency is displayed vertically, the lower frequencies
appear at the left of the screen and the higher ones at the right. The amplitude of the
lobes is calibrated. In the example in previous figure the noise level is at around 25
dBμV and the lobe with the highest signal level (third from the right) is at 70 dBμV.
The frequency range displayed (called span from hereon) can also be altered
using the horizontal cursors
screen frequency range in Spectrum Analyser mode between Full (the entire band),
500 MHz, 200 MHz, 100 MHz, 50 MHz, 32 MHz, 16 MH and 8 MHz (the latter one only
in terrestrial bands).
A vertical broken line, called marker, appears on the spectrum display to identify
the tuned frequency.
One of the applications of the PRODIG-5 operating as Spectrum Analyser is in
the search for the best orientation and position of the receiving antenna. This is
particularly important in UHF. Because such frequencies are involved, with wavelengths
ranging from 35 cm to 65 cm, if the antenna is shifted only a few centimetres, the
relationship between the picture, chrominance and sound carrier frequencies change,
affecting the quality of the picture in the receiver.
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Figure 35.- Spectrum analyser mode.
[6] keys. Therefore enables selecting the displayed
USER'S MANUAL. PRODIG-5
FREQ: 650.00 MHz
POWER: 65.6 dBµV
SPAN : 32 MHz
[6] keys between a
11/2013