Rev F Configuration 4-9
4
3. If the carriers adjacent to the ALC pilot carrier will be used in the active system, ensure that
they are on when balancing the E7 Line Extender. If these carriers cannot be turned on,
perform the following steps to adjust the ALC pilot carrier to compensate for the adjacent
carriers. If the ALC pilot carrier is the Forward High Balancing Carrier, proceed to Step 5 and
do not adjust ALC level.
a. At the headend, verify that the ALC pilot carrier is adjusted properly. Record the initial
level of the ALC pilot carrier.
b. Increase the ALC pilot carrier level as follows:
– 1dB if both adjacent carriers are turned off during balancing
– 0.75dB if only the upper adjacent carrier is turned off during balancing
– 0.25dB if only the lower adjacent carrier is turned off during balancing.
4. Set the E7 Line Extender in factory-aligned condition as follows:
■ If the E7 Line Extender has ALC or TLC, set the ALC/MAN Switch or TLC/MAN Switch
to the MAN position.
■ Remove any SEQ and SPB accessories installed in the FORWARD EQ and FORWARD
PAD plug-in areas and replace them with striplines, SEQ-0, or SPB-0 accessories.
■ If an Interstage SEQ is specified on the System Map, cut out the factory installed
jumper from the INTERSTAGE EQ plug-in area. Install the required SEQ accessory.
■ If the E7 Line Extender has TLC: determine the amount of cable loss preceding the line
extender in dB at the highest system frequency. For 10dB or less preceding cable loss,
set the CABLE SELECT Switch to 6dB; for greater than 10dB, set to 15dB.
Figure 4.2
Simplified Forward
Path Block Diagram
Te mp er a tu r e Need
Compensation?
Procedure
above 90°F (32°C)
or
below 50°F (10°C)
Yes Perform temperature compensation according to page 4-5.
Record the corrected values in the System High and Low Balancing
Carrier Levels calculation boxes as shown in steps 5 and 7.
If the air temperature changes more than 20° F (11° C) while balancing
the line extender, recalculate the temperature compensation.
between
50°F and 90°F
(10°C and 32°C)
No Copy the Forward High/Low Balancing Carrier Levels from the Map
Signal Information table on the FlexNet® 700 Series Line Extender
Data Sheet
to the calculation boxes in steps 5 and 7.
Note: The carriers adjacent to the ALC pilot carrier affect the performance of the ALC
circuit. If these adjacent carriers will be used in the active system, ensure that either the
adjacent carriers are on during ALC circuit adjustment, or the ALC carrier level has been
adjusted to compensate for the absence of these carriers. Otherwise, the ALC circuit or
carrier will need readjustment after these carriers are turned on.
Note: Using an adjusted ALC pilot carrier as the Forward High Balancing Carrier will
result in an improperly balanced line extender. Do not adjust the ALC pilot carrier level
if it is also used as the Forward High Balancing Carrier.
Port 1
Port
FORWARD PAD FORWARD EQ INTERSTAGE EQ
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