GatesAir Inc. CZF Manual De Usuario

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APEX
 Exciter Incorporating FLO
 Technology
Typical Settings for the More Critical Exciter Setups
Maintenance and Troubleshooting
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03/08/07
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Page: 5-11
WARNING: Disconnect primary power prior to servicing.
5.4
Typical Settings for the More Critical Exciter Setups
Some of the critical setups, which can have a large effect on exciter and transmitter opera-
tion, are given in Table 5-2. The remainder of the exciter setups should be fairly obvious
when viewing the various setup screens. For additional information concerning the exciter
setup screens, see Section 3.6, Details of the System Setup Screens, on page 3-32.
Table 5-2  Typical Settings For Some of the More Critical Exciter Setup Functions
Setup Screen and location in 
Technical Manual
Function
Typical Setting
Exciter Setup (screen 1 of 2)
Channel
Set to correct channel
Frequency Offset
Set to 0 or required offset in 
Hz, the limit is +/- 50 kHz.
Waveguide 
Provides group delay precorrection to 
compensate for waveguide group delay.
None, if waveguide group 
delay precorrection is not 
required.
Select waveguide type and 
enter length if waveguide 
group delay precorrection is 
required.
Power Limit
Limits maximum exciter 
power output (or transmitter 
power output, if exciter is used 
to control transmitter output 
power)
RTAC Setup
Filter Type: Use FLO BANDPASS for this exciter. 
Other Apex exciter application may use the following.
Standard
 if the standard D-Mask filter is used. Use Asymm (asymmetrical) if the 
sharp tuned filter (sometimes called “Cool Fuel”) is used or if the group delay for 
the transmitter is not symmetrical, such as when its output is reflected through an 
adjacent channel sharp tuned filter in order to combine the two transmitters. 
Exciter must be restarted to make filter change active.
Max. Peak Stretch (prevents nonlin correction 
peaks form over driving solid state amps).
3db (may be set lower on some 
transmitters.)
Off Air Mode (choices are Hold or Bypass)
Hold
Display
Chart Source (exciter spectrum analyzer display 
input)
Tx Post HPF
External I/O
VSWR Foldback Threshold (low limit)
0.25 Vdc, see Note 1
VSWR Foldback Threshold (high limit)
5.0 Vdc, see Note 1
VSWR Foldback (max RF power reduction)
50% of normal exciter output 
power, see Note 1
RF Cutoff (exciter output power level at which 
control logic switches to backup exciter)
50% of the normal exciter 
output power.
Note 1. Some transmitters use this feature for the transmitter output system VSWR foldback and other transmitters 
use a separate circuit for VSWR foldback. Consult the transmitter technical manual for instructions 
concerning VSWR foldback system and setup.