Cisco Cisco 1 GHz GainMaker Amplifier インストールガイド
Balancing the Forward Path
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with the design tilt (on the design print).
2 Is the output tilt within ±0.5 dB of the design tilt?
If the output tilt is within ±0.5 dB of the design tilt, proceed to the next
section, To Set the Output Level.
section, To Set the Output Level.
If the output tilt is more than design tilt, replace the forward input EQ with a
lower value.
lower value.
If the output tilt is less than design tilt, replace the forward input EQ with a
higher value.
higher value.
3 Measure the output tilt again, and then return to step 1.
To Set the Output Level
After setting the tilt, complete the following steps to select the proper pad values for
the line extender. The output level of the line extender is set by selecting the proper
pad value.
1 Connect the test probe to the forward main output test point.
2 Measure the output level at the highest design frequency, and compare this level
the line extender. The output level of the line extender is set by selecting the proper
pad value.
1 Connect the test probe to the forward main output test point.
2 Measure the output level at the highest design frequency, and compare this level
with the design level (on the design print).
3 Is the measured output level within ±0.5 dB of the design level?
If the output level is within ±0.5 dB of the design output level, proceed to
step 5.
step 5.
If the output level is more than the design output level, replace the forward
input pad with a higher value pad.
input pad with a higher value pad.
If the output level is less than the design level, replace the forward input pad
with a lower value pad.
with a lower value pad.
4 Repeat steps 2 and 3 until the output level is correct.
5 Proceed to the next section, To Set Up Automatic Gain Control.
5 Proceed to the next section, To Set Up Automatic Gain Control.
To Set Up Automatic Gain Control
This section provides procedures and tables for configuring and aligning the AGC in
the 1.2 GHz GainMaker Line Extender. AGC attenuator values are required to select
the proper AGC attenuator value based upon actual AGC pilot carrier output level.
See To Select the AGC Pad Value.
the 1.2 GHz GainMaker Line Extender. AGC attenuator values are required to select
the proper AGC attenuator value based upon actual AGC pilot carrier output level.
See To Select the AGC Pad Value.
Note:
Output levels are measured at the pilot frequency.
The standard single-pilot AGC makes line extender output adjustments based on
the level of the pilot frequency carrier. Activate the pilot carrier with its final
unscrambled video source before beginning balance and alignment.
the level of the pilot frequency carrier. Activate the pilot carrier with its final
unscrambled video source before beginning balance and alignment.