Johansson 9744MC, Руководство пользователя

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Digital SCR Multiswitch (Ref: 9744MC, 9746MC, 9748MC)
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3. C
ONFIGURATION OF THE MODULE
STB Power to Trunk Switch
 OFF

This is the default state, as trunks will feed all cascaded units and the LNB. Power
comes from DC inserted at the “DC Input” of 1 or more cascaded units.
 ON

The STB will feed the unit and the LNB. This is only allowed when 1 unit is used in
the system. From the moment 2 are cascaded, the position “OFF” should be selected.
Otherwise, 1 STB will need to feed all units.
There is always DC pass-through on the trunks (Sat only).
Terrestrial amplifier
The Terrestrial trunk has an integrated amplifier that can be turned into bypass- or amplified-
mode. Only in bypass mode, DOCSIS signals can pass through.
The Terrestrial trunk should always be terminated with a 75-Ohm terminator.
Diagnostic LED’s:
Special high power startup mode: status LED’s blink alternating GREEN and RED .
This is a special mode active when starting up the device (when the trunks are powered, not
when STBs power the unit). In this mode, the unit will consume the maximum power. This
allows the installer to check that there will be adequate power for the system under full (SCR)
load. This “High power startup” mode gives the installer a 15-second window to check the
performance of the power supplies. After 15 seconds, the unit will go into 1 of the 2
operational modes (SCR or Legacy).
During the 15 seconds, the power-up diagnostic LED of all 974xMC units should be checked.
 If the voltage level on the trunks is too low for the unit to operate, then the Power up
Diagnostic LED will be orange,

connect an extra DC supply to the DC input.
 If the voltage level on the trunks is OK, then the LED will be green.