User Manual

SECTION 2: FACTORY TEST PROCEDURE
IP4HPVGPS-MRFCCRpt.doc Page 13
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Transmit Data
Perform the following steps to adjust transmit data:
Step 1 Use IPMessage to set the transmit power to 0.
Step 2 Using the x=2000,n command of IPMessage to generate transmit data messages while
observing the transmitted signal on the HP RF communications test set, adjust pot R33 for
minimum frequency error while transmitting data messages.
Step 3 Turn potentiometer RV1 fully counterclockwise.
Step 4 Adjust RV2 for deviation of 4.9 kHz.
Step 5 Using calibrated base station, and monitoring the uplink received data quality on the base
station's Hyperterminal screen, slowly turn RV1 clockwise until consistent data quality
readings of 240 - 248 are achieved using 2000 character test messages. Data quality
reading should not be less than 240 for 2000 character messages.
If unable to reach the data quality readings then ask for Technical Support. Poor data
quality readings are indicative of poor group delay performance, or other defect.
Step 6 Verify transmit deviation, frequency error, and transmitting data messages quality and record
this data on the Test Data Sheet.
Power Setting
Perform the following steps to adjust the transmit power control:
Step 1 Attach a power attenuator to the transmit port of the radio.
Step 2 Using the x=2000,n command of IPMessage, and while monitoring the transmit power level
on the HP communications test set, check the level of the transmit power. Using IPMessage
set the power setting to txpower=0. The radio should have an output power level of
approximately 1 mW. Record this value on the Test Data Sheet.
Step 3 Using IPMessage send the txpower= command to increase the power level settings until 40
Watts of output power is obtained. Record this value on the Test Data Sheet. Note that
values on the table are to plot the codes vs. power output. The 40-Watt setting can be a
code not on the table. Adjust txpower until the code is found that does not exceed 40.0
Watts. Record this value on the Test Data Sheet.
Do not to exceed 40 Watts of output power, as this may reduce the life of the amplifier.