Teleste CXE180, Руководство пользователя

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User Manual CXE180
59300401 Rev.001
26.5.2010 10(12)
Adjustments
Downstream signal path
The output stage uses a GaAs hybrid to improve RF performance over the
entire 47 to 1006 MHz passband. The distribution path, through the use of plug-
in output modules (Figure 4 pos.11), can be set up for a variety of output
configurations. Refer to the ‘ Table 1. Output modules with corresponding
nominal attenuation values ’ . During amplifier adjustment the plug-in unit position
for output module must be equipped at least with the 0 dB module.
Set the mid stage slope of the amplifier according to the network plan
calculation by means of the mid stage slope selection jumper (Figure 4 pos. 8).
The available options are “flat” (0 dB) or “sloped” (8 dB).
Set the output slope of the amplifier according to the network plan calculation by
means of cable simulator (Figure 4 pos. 6). The output level of the amplifier is
adjusted with the variable input attenuator (Figure 4 pos. 4). Measurements on
the output are made at the -20 dB output test point (Figure 4 pos. 10). Make
final adjustment of the output slope with the variable input equaliser (Figure 4
pos. 5).
If you are having trouble obtaining the expected output level then check the
input test point (Figure 4 pos. 2) to verify that the level is as expected at the
input of the amplifier. The mid stage gain selection jumper (Figure 4 pos. 7) can
be used to reduce gain with 8 dB if input levels are enough to cause a high
distortion level in the input amplifier.
The output stage uses a GaAs hybrid to improve RF performance over the
entire 47 to 1006 MHz passband. The output ports, through the use of passive
plug-in output modules (Fig. 4 pos. 11); can be set up for a variety of output
configurations. Refer to ‘Table 1. Output modules with corresponding nominal
attenuation values’.
Module Functionality Output 1 Output 2
AC6120 0 dB output module, 1 output in use
0 dB not used
AC6112 1/12 dB tap, 2 outputs in use
-1 dB -12 dB
AC6116 1/16 dB tap, 2 outputs in use
-1 dB -16 dB
AC6119 1/20 dB tap, 2 outputs in use
-1 dB -20 dB
AC6124 Two-way splitter, 2 outputs in use
-4 dB -4 dB
AC6128 2/9 dB tap, 2 outputs in use
-2 dB -9 dB
Table 1. Output modules with corresponding nominal attenuation values