Motorola Astro Digital Mobile Radio Xtl5000 Basic 6881096c73 O Manual

							6881096C73-OJune 11, 2003
Radio Alignment Procedures: Radio Information 6-3
6.3 Radio Information
Figure 6-3 shows a typical Radio Information screen. All of the data appearing here is informational 
and cannot be changed.
Figure 6-3.  Radio Information Screen
6.4 Transmitter Alignments
6.4.1 PA Bias 1 Alignment
NOTE:This alignment is required after replacing (or servicing) the transceiver board.
The PA Bias 1 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 6-2. Set power supply current limit to 3 A.
2. Select PA  B i a s  1 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.Table 6-1.  PA Bias 1 Alignment RF Power Amplifier Devices
Band/Power LevelDevice
700–800 MHz 35 W/15 W Motorcycle Final1
Table 6-2.  Power Supply Voltage Settings
Band/Power LevelSupply Voltage (V)Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15 
						

							June 11, 20036881096C73-O
6-4Radio Alignment Procedures: Transmitter Alignments
Figure 6-4.  PA Bias 1 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.
6.4.2 PA Bias 2 Alignment
NOTE:This alignment is required after replacing (or servicing) the transceiver board. 
The PA Bias 2 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 6-5. Set power supply current limit to 3 A. Table 6-3.  PA Bias 1 Alignment Device Bias Current
Band/Power LevelDevice bias current (mA)
700–800 MHz 35 W/15 W Motorcycle 250
Table 6-4.  PA Bias 2 Alignment Amplifier Devices 
Band/Power LevelDevice
700–800 MHz 35 W/15 W Motorcycle Final2
Table 6-5.  Power Supply Voltage Settings
Band/Power LevelSupply Voltage (V)Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15 
						

							6881096C73-OJune 11, 2003
Radio Alignment Procedures: Transmitter Alignments 6-5
2. Select PA  B i a s  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 LevelDevice bias current (mA)
700–800 MHz 35W/15W Motorcycle 250
Table 6-7.  PA Bias 3 Alignment Amplifier Devices
Band/Power LevelDevice
700–800 MHz 35 W/15 W Motorcycle Driver
Table 6-8.  Power Supply Voltage Settings
Band/Power LevelSupply Voltage (V)Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15 
						

							June 11, 20036881096C73-O
6-6Radio Alignment Procedures: Transmitter Alignments
2. Select PA  B i a s  3 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 6-6.  PA Bias 3 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.
6.4.4 Reference Oscillator Alignment
Radios are shipped from the factory with a worst-case frequency error of ±500 Hz for 700–800 MHz. 
These specifications are tighter than the more stringent FCC requirements of ±1.5 ppm for the 700–
800 MHz bands.
For radios that have been in storage for over six months from the factory ship date, the reference 
oscillator should be checked when the radio is initially deployed to the field. It is strongly 
recommended that the reference oscillator be checked every time the radio is serviced or at least 
once a year, whichever comes first.
The crystal contained in the reference oscillator naturally drifts over time due to its aging 
characteristic. Periodic (annual) adjustment of the reference oscillator is important for proper radio 
operation.
Improper adjustment can result in both poor performance and interference with other users operating 
on adjacent channels.Table 6-9.  PA Bias 3 Alignment Device Bias Current
Band/Power LevelDevice bias current (mA)
700–800 MHz 35 W/15 W Motorcycle 100 
						

							6881096C73-OJune 11, 2003
Radio Alignment Procedures: Transmitter Alignments 6-7
This test can be done with either the R-2670 Communication Analyzer or the Agilent 8901 
Modulation Analyzer.
 Initial set up using the R-2670 Communication Analyzer:
- RF Control: MONITOR
- B/W: WB
- Freq: RSS frequency under test
- Attenuation: 20dB
- Mon RF in: RF I/O
- Meter: RF Display
- Mode: STD
- Input Level: uV or W
- Display: Bar Graphs
- Squelch: Mid-range or adjust as necessary
 Initial set up using the Agilent 8901 Modulation Analyzer:
- Press the green Automatic Operation button on the analyzer. 
- Press the FREQ key.
- Type 7.1 followed by the SPCL button to set the 8901 Modulation Analyzer for maximum 
accuracy.
1. Select Reference Oscillator from the Tuner Main Menu (Figure 6-7).
Figure 6-7.  Reference Oscillator Window
2. If you are using the R-2670 analyzer, enter the frequency displayed on the Tuner screen in 
the RF control section of the R-2670. Under the Meter section of the display, choose 
RF DISPLAY.
3. Left-click the PTT Toggle button on the screen to make the radio transmit. The screen 
indicates whether the radio is transmitting.
4. Wait five seconds until the analyzer reading stabilizes, and then record the transmitter 
frequency. 
						

							June 11, 20036881096C73-O
6-8Radio Alignment Procedures: Transmitter Alignments
5. Adjust the reference oscillator’s softpot value until the measured value is as close as possible 
to the frequency shown on the screen. Allow approximately five seconds for the analyzer 
frequency reading to stabilize after each change. See Table 6-10. 
6. Left-click the Program All button on the screen to dekey the radio and save the tuned values.
7. Left-click the Close button on the screen to return to the Tuner Main Menu.
6.4.5 Power Detector Calibration
NOTE:This alignment is required after replacing (or servicing) the transceiver board.
The power detector calibration alignment procedure adjusts the buffer gain for the forward power 
detector to minimize radio power variation from radio to radio.
NOTE:Antenna port should be terminated with calibrated power meter through a 30 db RF pad.
1. Set the power supply voltage and current limit as indicated in Table 6-11.
2. Select Power Detection Calibration from the Tuner Main Menu.
Figure 6-8.  Power Detection Calibration Alignment Screen
3. Left-click the PTT Toggle button to transmit at indicated frequency.
4. Adjust softpot value until target power is achieved.
5. Left-click the PTT Toggle button to disable transmit mode. Table 6-10.  Reference Oscillator Alignment
BandTa r g e t
800 MHz ±100 Hz
Table 6-11.  Power Supply Voltage Settings
Band/Power LevelSupply Voltage (V)Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15 
						

							6881096C73-OJune 11, 2003
Radio Alignment Procedures: Transmitter Alignments 6-9
6. Left-click the Program All button to save tuned value.
7. Left-click Close button to close screen and return to the Tuner Main Menu.
6.4.6 Tx Power Characterization
NOTE:This alignment is required after replacing (or servicing) the transceiver board.
The Tx Power Characterization alignment procedure characterizes power tuning so that Tx power 
can be adjusted with CPS software. You will transmit at two power levels for each test frequency and 
record the measured power level with 0.1 W resolution.
NOTE:The antenna port should be terminated with a calibrated power meter through a 30 db RF 
pad.
1. Set the power supply voltage and current limit as indicated in Table 6-12.
2. Select Tx Power Characterization from the Tuner Main Menu.
Figure 6-9.  Tx Power Characterization Alignment Screen
3. Left-click in the first box of the Measured Power 1 column. A green circle will appear to the 
left of box indicating active characterization point.Table 6-12.  Power Supply Voltage Settings
Band/Power LevelSupply Voltage (V)Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15 
						

							June 11, 20036881096C73-O
6-10Radio Alignment Procedures: Transmitter Alignments
4. Left-click the PTT Toggle button to transmit at indicated frequency and record power 
measurement with 0.1 W resolution. The green circle will turn red indicating that the radio is 
transmitting.
5. Left-click the PTT Toggle button to disable transmit mode.
6. Enter the power measurement with 0.1 W resolution overwriting any value that may reside in 
the box from previous tuning.
7. Left-click in the first box of the Measured Power 2 column. The green circle will move to the 
left of this box indicating it has become active characterization point.
8. Repeat steps 4-6.
9. Repeat steps 3-8 for the remaining frequencies.
10. Left-click the Program All button to save tuned value.
11. Left-click Close button to close screen and return to the Tuner Main Menu.
6.4.7 Tx Current Limit
NOTE:This alignment is required after replacing (or servicing) the transceiver board or after there 
has been a change in the CPS-adjustable power level.
The Tx Current Limit alignment procedure tunes the Tx current-limiting protection. If you increase the 
CPS-adjustable power level, then the current limit must be retuned so the radio can achieve the 
desired power level. If you decrease the CPS-adjustable power level, the current limit can be retuned 
to increase protection. You must first determine the test frequency at which maximum transmit 
current occurs and then tune on that test frequency.
NOTE:The antenna port should be terminated with a calibrated power meter through a 30 dB RF 
pad.
1. Set the power supply voltage and current limit as per Table 6-13.
Table 6-13.  Power Supply Voltage Settings
Band/Power LevelSupply Voltage (V)Supply Current Limit (A)
700–800 MHz 35 W/15 W Motorcycle 13.6 15 
						

							6881096C73-OJune 11, 2003
Radio Alignment Procedures: Transmitter Alignments 6-11
2. Select Tx Current Limit from the Tuner Main Menu.
Figure 6-10.  Tx Current Limit Alignment Screen
3. Use a slider or the spin buttons to change any one softpot value to 255.
4. Left-click the Program All button to save the tuned value. All softpots will change to 255, and 
transmit-current limiting will be disabled.
5. Left-click in upper softpot box.
6. Left-click the PTT Toggle button to transmit and record radio the transmit current drain. The 
tuner software uses a high CPS-adjustable power-level setting when transmitting.
7. Left-click the PTT Toggle button to disable transmit mode.
8. Repeat steps 6-8 for each test frequency to determine the frequency at which maximum 
transmit current drain occurs.
9. Once the proper test frequency is determined, left-click the PTT Toggle button to transmit 
and record transmit power on that test frequency.
10. Decrease the softpot value until transmit power degrades by 5%, and then left-click the PTT 
Toggle button to disable transmit.
11. Increase the softpot value to set the proper operating head room.
Table 6-14.  Transmit Current Limit Offset
Band/Power LevelCurrent Limit Offset
700–800 MHz 35 W/15 W Motorcycle 8 
						

							June 11, 20036881096C73-O
6-12Radio Alignment Procedures: Transmitter Alignments
12. Left-click the Program All button to save tuned value.
13. Left-click the Close button to close screen and return to the Tuner Main Menu.
6.4.8 Tx Deviation Balance (Compensation)
NOTE:This alignment is required after replacing (or servicing) components on the transceiver board.
The Tx Deviation Balance (Compensation) alignment procedure balances the modulation 
contributions of the low- and high-frequency portions of a baseband signal. Proper alignment is 
critical to the operation of signaling schemes that have very low frequency components (for example, 
DPL) and could result in distorted waveforms if improperly adjusted. This procedure needs to be 
performed at multiple frequencies to allow for proper alignment across the entire RF band. The RF 
band is divided into frequency zones with a calibration point (value) in each zone. When performing 
this tuning procedure the PTT Tone Low generates an 80 Hz modulation frequency. The deviation 
level of this 80 Hz tone is used as the reference level for adjusting the deviation level of the PTT 
Tone High, which is a 3 kHz modulation frequency.
This test can be done with either the R-2670 Communication Analyzer or the Agilent 8901 
Modulation Analyzer. The method of choice is the R-2670 Analyzer.
 Initial set up using the R-2670 Communication Analyzer:
- Connect a BNC cable between the DEMOD OUT port and the VERT/SINAD DIST/DMM 
COUNTER IN port on the R-2670.
- Press the SPF key on the R-2670 to display the SPECIAL FUNCTIONS MENU. Move the 
cursor to High Pass, and select 5 Hz on the soft key menu. Select 20 kHz for the Low 
Pass setting.
- In the RF Control section of the R-2670, enter the frequency displayed on the Tuner 
screen. Move the cursor to the B/W setting and select WIDE 
±100 kHz on the soft key 
menu.
- Place the R-2670 cursor in the Display zone. Select AC VOLTS on the soft key menu. 
Move the cursor to the Range setting and select AUTO.
 Initial set up using the 8901 Modulation Analyzer:
- Press the FM MEASUREMENT button. (The Error 03-input level too low indication is 
normal until an input signal is applied.)
- Simultaneously press the Peak - and Peak + buttons. Both LEDs on the buttons should 
light.
- Press the 15 kHz LP filter key.Table 6-15.  Transmit Current Limit Devices 
Band/Power LevelDevices
700–800 MHz 35 W/15 W Motorcycle Final1 Final2 Driver