6881096C73-O June 11, 2003
Radio Alignment Procedures: Transmitter Alignments 6-5
2. Select PA Bias 2 from the Tuner Main Menu. When the screen is opened, the radio enters a
special bias tune mode and radio current increases by approximately 100 mA.
Figure 6-5. PA Bias 2 Alignment Screen
3. Read baseline current from current meter on power supply.
4. Add baseline current to device bias current to calculate target current.
5. Left-click the Bias Toggle button to apply bias to gate of device.
6. Adjust softpot value until target current is achieved within
±10%
7. Left-click the Bias Toggle button to remove bias from gate of device.
8. Left-click the Program All button to save tuned value.
9. Left-click Close button to close the screen and return to the Tuner Main Menu.
6.4.3 PA Bias 3 Alignment
NOTE: This alignment is required after replacing (or servicing) the transceiver board.
The PA Bias 3 alignment procedure adjusts the drain bias current in one of the RF power amplifier
devices:
NOTE: The antenna port should be terminated with a 50-ohm load while tuning.
1. Set the power supply voltage as indicated in Table 6-8. Set power supply current limit to 3 A.
Table 6-6. PA Bias 2 Alignment Device Bias Current
Band/Power Level Device bias current (mA)
700–800 MHz 35W/15W Motorcycle 250
Table 6-7. PA Bias 3 Alignment Amplifier Devices
Band/Power Level Device
700–800 MHz 35 W/15 W Motorcycle Driver
Table 6-8. Power Supply Voltage Settings
Band/Power Level Supply Voltage (V) Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15
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