Cisco Cisco 1 GHz GainMaker Amplifier 安装指南
Chapter 3 Balancing and Setup
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Switch S1 Position Information for AGC Stations
Position 1
Thermal Setup Mode
Thermal Setup Mode
Position 2
Manual Setup Mode
Manual Setup Mode
Position 3
AGC Operational Mode
AGC Operational Mode
A thermistor (thermal) driven
circuit on the line extender sets
the DC control voltage that
drives the Bode.
This circuit detects the line
extender’s internal temperature
and generates the proper level
of DC control voltage, setting
the proper loss characteristics of
the Bode with respect to the
current outdoor temperature.
Note: This is the same as the
“Thermal” toggle switch setting
on most prior AGCs.
circuit on the line extender sets
the DC control voltage that
drives the Bode.
This circuit detects the line
extender’s internal temperature
and generates the proper level
of DC control voltage, setting
the proper loss characteristics of
the Bode with respect to the
current outdoor temperature.
Note: This is the same as the
“Thermal” toggle switch setting
on most prior AGCs.
The Manual Backoff
potentiometer sets the DC control
voltage that drives the Bode.
Manually adjusting the Manual
Backoff potentiometer sets the
proper loss characteristics of the
Bode with respect to the current
outdoor temperature.
Manual adjustment is done by
monitoring the line extender RF
output level and adjusting the
potentiometer to reduce the gain
“x” dB from the full gain
(minimum loss) of the
potentiometer setting.
The value of “x” (gain reduction)
is dependent upon outside
temperature and is determined by
consulting the Manual Backoff
Chart.
Note: This is the same as the
“Manual” toggle switch setting on
some prior AGCs.
potentiometer sets the DC control
voltage that drives the Bode.
Manually adjusting the Manual
Backoff potentiometer sets the
proper loss characteristics of the
Bode with respect to the current
outdoor temperature.
Manual adjustment is done by
monitoring the line extender RF
output level and adjusting the
potentiometer to reduce the gain
“x” dB from the full gain
(minimum loss) of the
potentiometer setting.
The value of “x” (gain reduction)
is dependent upon outside
temperature and is determined by
consulting the Manual Backoff
Chart.
Note: This is the same as the
“Manual” toggle switch setting on
some prior AGCs.
The AGC detector circuit monitors
the AGC pilot carrier level at the
input to the AGC module. The
detected AGC pilot carrier level
variations cause a proportional
variation of the DC control
voltage that drives the Bode.
Important: The switch must be
left in this position after initial
balancing in order for the AGC to
function with the Bode properly.
The AGC and Bode combination
thus cause offsetting gain and
slope variations to occur as
needed, holding the actual line
extender output stable.
Note: This is the same as the
“Auto” toggle switch setting on
all prior AGCs.
the AGC pilot carrier level at the
input to the AGC module. The
detected AGC pilot carrier level
variations cause a proportional
variation of the DC control
voltage that drives the Bode.
Important: The switch must be
left in this position after initial
balancing in order for the AGC to
function with the Bode properly.
The AGC and Bode combination
thus cause offsetting gain and
slope variations to occur as
needed, holding the actual line
extender output stable.
Note: This is the same as the
“Auto” toggle switch setting on
all prior AGCs.
Note: AGC operational mode is used only after the station has been initially balanced in
either thermal or manual setup mode.
either thermal or manual setup mode.
Switch S1 Positions for Manual Stations
The manual version of the 1.2 GHz GainMaker Line Extender does not have a Bode
network installed. Therefore, switch S1 has no function in the manual version of the
product.
network installed. Therefore, switch S1 has no function in the manual version of the
product.
Switch S1 Positions for Thermal Stations
The mode of thermal compensation you select for a thermal station determines the
position in which you place switch S1.
position in which you place switch S1.
Position 1 - Selects line extender only compensation mode
Position 2 - Not used
Position 3 - Selects line extender and coax compensation mode
Bode Network
The Bode Network, or Bode, is an interstage variable attenuation and slope network