4-6 FlexNet
®
700 Series Line Extender Rev F
4
If the temperature is below 50°F (10°C) or above 90°F (32°C), perform temperature compensation as
follows:
➤ To compens at e fo r te mp e r a t u re
1. Record the System Forward High and Low Balancing Carrier levels from the E7 Line Extender
data sheet below. Perform the calculation to get the adjusted output levels.
2. For both forward balancing carriers, note the loss (in dB at the carrier frequency) due to the
cable preceding the unit under test. Also note the air temperature. Use these values and the
TCV (temperature compensation value) chart on page 4-7 to obtain a temperature
compensation value for this section of cable for each balancing carrier. Record both TCVs in
the calculation box in Step 1 and on the FlexNet® 700 Series Line Extender Data Sheet.
3. Use the temperature compensated forward balancing carrier levels for Forward Balancing or
Forward Field Testing.
4. Optional: Repeat Steps 2 and 3 for the return balancing carriers. Use these temperature
compensated levels for Return Balancing or Return Field Testing.
+ =
System Forward High
Balancing Carrier Level
TCV For High Carrier Adjusted Forward High
Balancing Carrier Level
+ =
System Forward Low
Balancing Carrier Level
TCV For Low Carrier Adjusted Forward Low
Balancing Carrier Level
Note: To obtain the temperature compensation value on the TCV Chart (page 4-7): Find
the point on the chart corresponding to your cable loss and temperature values. Then
find the TCV line nearest this point. The dB value label on that line is your TCV.
Note: Example: Your cable loss is 25dB. The air temperature is 25°F (-5°C). The point on
the graph corresponding to these two values is between the 0.5 and 1.0dB lines, but
closer to the 1.0dB line. (The dotted lines mark the halfway-between-lines points on the
graph.) The TCV is then 1.0dB.
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