Promax US TV EXPLORER II, User Manual

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USER’S MANUAL. US TV EXPLORER II
Page 40 01/2008
Press the [17] key to see on screen the measurement CONFIGURATION .
By means of the Threshold Attenuation option is possible to adjust the maximum
difference between the pilots reference level from -55 to 10 dBmV.
Later, by means of the horizontal cursors [6] key, select the Calibrate
function (see the following figure). Wait for some seconds until the calibration process
for three pilots is completed:
MEASURING REF.
is indicated on screen while this process
is in progress.
EXIT CALIBRATE
10
0
-10
-20
FREC:
REF:
TEST:
ATT: MHz
dBµV
dBµV
dB
2130.99
100.3
99.1
1.2
1403.94
90.2
90.2
0.0
1294.89
84.7
84.5
0.2
Figure 16.- SAT IF Test. Satellite band.
The calibration process must be carried out over the point of the installation which
is taken as reference, i.e. usually the headend. During this process is determined the
number of pilot frequencies to check, from one to three, in addition to the reference level
for pilots. In order to determine the number of pilots, the equipment takes the higher
found level and verifies that the other pilots have a non lower level to the reference one
plus the defined threshold level. If the pilot agrees this condition it will show on screen.
2.- MEASUREMENT OF THREE PILOTS THROUGHOUT THE NETWORK
Once US TV EXPLORER II has been calibrated, start to make level
measurements in the different distribution outlets using the
EXPLORER
. On the
screen will appear the attenuation values for the three pilot frequencies measured in the
outlet plate (see the following figure).