User's Manual

MODEL 2130 MARKER BEACON
Rev. A April, 2005 5-5
This document contains proprietary information and such information may not be disclosed to others for any
purposes without written permission from SELEX Sistemi Integrati Inc.
Vm = Minimum voltage
h. Read current modulation percentage on Monitors>> Data>>Integral screen. Compare to the calculated reading. If
they do not agree adjust Monitors>> Configuration >> Offsets and Scale factors to correct.
i. Shut down the Marker Beacon, disconnect all external test equipment, and reconnect all cables.
j. Return Marker Beacon to normal operation.
5.3.4 Forward Power, Reflected Power and VSWR BITE Check
5.3.4.1 Test equipment required
a. Facility built in wattmeter
b. Bird Wattmeter Thuline body with 5 Watt, 50-125 MHz, 1 Watt or less, 50-125 MHz or alternately an HP 437B power
meter or equivalent.
c. PMDT
5.3.4.2 Procedure
a. Remove system power and insert wattmeter with 5W, 50-125 MHz element into RF output transmission line.
b. Place a Tee and two 50 ohm loads on the output cable to the antenna.
c. Turn on Marker Beacon. After Marker Beacon initializes to the normal state, type in the system password.
d. Place equipment in bypass mode.
e. Adjust wattmeter element to read forward power. Note wattmeter indication. Compare with indication of internal test
equipment in Transmitters>>Data>>Power Sensor Data. Compute the error in the Forward Power Bite reading
using:
IndicationPowerentTestEquipm
IndicationPowerBITEIndicationPowerTestEq
Error
__
___._
−
=
f. Verify that the error is not within the tolerance of Table 3-1 perform 5.3.5.
g. Insert wattmeter with 1W or less, 50-125 MHz element into RF output transmission line.
h. Set wattmeter element to read reflected power. Note wattmeter indication. Compare with indication of internal test
equipment in Transmitters>>Data>>Power Sensor Data Reflected Power.
IndicationPowerentTestEquipm
IndicationPowerBITEIndicationPowerTestEq
Error
__
___._
−
=
i. If the difference is not within the tolerance for Table 3-1 perform 5.3.5
j. Calculate the VSWR using the following formula:
VSWR
FWD REV
FWD REV
=
+
−
Where FWD = Forward Power and REV = Reverse Power.
k. Compare with internal test equipment indication. Calculated VSWR and screen indication must agree within the
tolerance of Table 3-1 if not, perform 5.3.5.
l. Shut down the Marker Beacon, disconnect all external test equipment, and reconnect all cables.
m. Return system to normal operation.