BIRD 428B-83H-01-C-110, Инструкция по установке и эксплуатации

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TX RX Systems Inc. Manual 7-9487-3 05/05/11 Page 23
GTR8000 ATTENUATOR ADJUSTMENT
There are two configurations of the GTR8000,
those with a site RMC (systems expandable past 6
stations) and those without the site RMC (systems
limited to a maximum of 6 stations). The attenua-
tion adjustments within the GTR8000 are different
for both configurations as follows;
For systems with the site RMC
set the site RMC attenuation to 8 dB
set the cabinet RMC attenuation to 13 dB
For systems without the site RMC
set the cabinet RMC attenuation to 7 db
The attenuation value of either the site or cabinet
RMC is determined by the position of the attenua-
tor switches located on the RMC assembly, refer to
Figure 24 . Each of the first 5 attenuation switches
provides 1, 2, 4, 8, or 16 dB of attenuation when
the associated switch is in the ON position. The
sixth switch is unused. The attenuation is additive
so a maximum of 31 dB of attenuation would be
realized if all of the switches were in the ON posi-
tion at the same time.
When the MCU style is connected to
the GTR8000 Six-Pack you will need
to add 3 dB pads inline with the out-
puts from the base control unit to the
receivers.
Reserve Gain Adjustment Procedure
The factory default programmable attenuation set-
ting for reserve gain is 3.0 dB. This is the initial set-
ting that is programmed into your system when you
first turn it on. You will need to adjust this value to
optimize your system. This is done through soft-
ware interface via the menu select keys. Your set-
ting will be stored in system memory until you
change it again even if the equipment is powered
down. The programmable attenuation for optimiz-
ing your reserve gain is adjustable from 0 to 15.5
dB in 0.5 dB increments. To adjust the value per-
form the following steps.
NOTE
Figure 24: Adjusting the Site or Cabinet RMC attenuation.
In the example above the SITE RMC attenuation is set to 8 dB
and the CABINET RMC attenuation is set to 13 dB.