______________________________________________
HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
210
8.5.2.5 VSWR Protection Check
•
Precise Method:
STEP 1:
Connect a 50 ohm termination to the module RF input. Connect a signal
generator, test amplifier, and power meter to the module output per
Figure A-7.
Figure 8-9 VSWR Protection Test Setup
STEP 2:
Apply 50 V DC and enable the module.
STEP 3:
Set the signal generator to the Aural carrier frequency and apply 94.5
Watts CW into the PA module RF output.
STEP 4:
Slowly adjust R8 CCW until the module disables and gives a blink code
of one on the red LED.
STEP 5:
Reduce the signal generator level and enable the module. Slowly raise
the signal generator level while monitoring the power applied to the
module. The module should disable between 90 and 100 Watts. If not,
readjust R8 as required.
STEP 6:
Turn off the 50 V DC.
•
Field Calibration
If the control card has functioning power supplies, measure the voltage at U6 pin 4 and
adjust R8 for the same voltage on the new board.
OR
Measure the resistance from wiper of R8 to ground and adjust R8 for the same resistance
value.