5-4

Radio Alignment Procedures: Transmitter Alignments

 

 

NOTE: Reference oscillator alignment is required after replacing (or servicing) the transceiver board.

To align the reference oscillator:

1. Select the Reference Oscillator alignment screen. See Figure 5-5.

Figure 5-5. Reference Oscillator Alignment Screen

2.Left-click the PTT Toggle button on the screen to make the radio transmit. The screen indicates whether the radio is transmitting.

3.Measure the transmit RF frequency with your communications system analyzer.

4.Adjust the reference oscillator’s softpot value until the measured value is as close as possible to the frequency shown on the screen. See Table 5-1.

Table 5-1. Reference Oscillator Alignment

Band

Target

 

 

UHF R2 (450–488 MHz)

±100 Hz

 

 

5.Left-click the Program All button on the screen to dekey the radio and save the tuned values.

6.Left-click the Close button on the screen to return to the Transmitter Alignments menu.

5.5.3Transmit Power Alignment

This alignment procedure adjusts the transmit power of the radio and must be performed for two different power levels (Low and High), at multiple frequencies for each power level, to allow for proper alignment across the entire RF band. (The mid-power level is available to be tuned, but it cannot be used.) The RF band is divided into frequency zones with a calibration point (value) in each zone.

NOTES:

The same softpot attenuation value will result in different radio output power levels at different frequencies.

All power measurements are to be made at the antenna port.

Transmit Power alignment is required after replacing (or servicing) the transceiver board.

November 11, 2004

6881094C12-A

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Motorola SSETM 5000 service manual Transmit Power Alignment, Band Target