User's Manual

Table Of Contents
APEX Exciter Incorporating FLO Technology
Details of the Exciter Status Screens Navigating the LCD Display Screens
2604s300.fm
03/08/07 888-2604-001 Page: 3-29
WARNING: Disconnect primary power prior to servicing.
For both of these entries the selectable range, entered on the touch screen number pad,
is 0 to 4095. The number selection represents a dc voltage in millivolts. For example,
a setting of 3000 represents 3000 mVdc or 3 Vdc.
These analog channels have a total of four inputs and two outputs for the UHF Exter-
nal I/O board and two inputs and two outputs for the VHF External I/O board.
When performing the loopback test, the results appear on the External I/O board status
screen, Figure 3-25. The analog output A and B voltages appears on the appropriate analog
1 through 4 inputs. Analog 1 input also appears by the foldback entry as a percentage.
For example, if analog loopback is enabled and analog output A is set for 2000 and B is set
for 3000, analog inputs 1 and 3 will measure within a few tenths of a volt of 2 Vdc, analog
inputs 2 and 4 will measure within a few tenths of a volt of 3 Vdc. The VSWR foldback
percentage will be based on the relative value of the loopback voltage (V
LB
) compared to
the External I/O setup screen low voltage (V
LT
) and high voltage (V
HT
) VSWR foldback
thresholds.
The analog loopback function produces outputs at various pins of J1, the pinout is as
follows:
When analog output A is set to a value, such as 2500, 2.5 Vdc will appear at the ana-
log 1 output, which is J1 pin 4 for UHF and J1 pin 7 for VHF. This output is present if
loopback is enabled or disabled and the connection to J1 has a high impedance.
When analog output B is set to a value, such as 3000, 3.0 Vdc will appear at the ana-
log 2 output, which is J1 pin 17 for UHF and J1 pin 8 for VHF. This output is present
if loopback is enabled or disabled and the connection to J1 has a high impedance.
When loopback is enabled, the voltage set by analog output A or B is present at the
appropriate analog input J1 connectors.
The pinouts for UHF analog inputs 1 through 4 are J1-12, J1-13, J1-3, and J1-16 re-
spectively.
The pinouts for VHF analog inputs 1 and 2 are J1-15 and J1-16 respectively.
Foldback Percentage
V
LB
V
LT
V
HT
V
LT
----------------------------
100×=