Motorola CDM1250, Basic Service Manual

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4-6 Radio Programming and Tuning Procedures
Table 4-4: Reference Oscillator Warp Specifications*
*These values are up-to-date as of the print date. For the latest values and procedures, refer to the
Tuner online help.
4.4.3 DAC Tuning (LowBand radios only)
Perform the DAC tuning procedure as follows:
1. Under the Tx Align menu, select Transmit Power, then select DAC .
2. Press the PTT Toggle button to key up the radio.
3. Select DAC1 by clicking on it's slider bar.
4. Measure the transmit power and compare it with the specification limits for DAC1 Power as
defined in Table 4-5.
5. If the measured transmit power is outside the specification limits, adjust the slider, spin, or edit
control until the transmit power is within the specification limits.
6. Repeat Steps 3 - 5 for DAC2 .
7. Press PTT Toggle again to dekey the radio.
8. Exit the DAC tuning function.
Table 4-5: DAC1 & DAC2 Power Specifications*
*These values are up-to-date as of the print date. For the latest values and procedures, refer to the
Tuner online help.
RF Band Target
UHF (450-527 MHz) ±30 Hz
UHF (450-512 MHz) ±30 Hz
UHF (403-470 MHz) ±30 Hz
VHF (136-174 MHz) ±30 Hz
LowBand (29.7-36 MHz) ±30 Hz
LowBand (36-42 MHz) ±30 Hz
LowBand (42-50 MHz) ±30 Hz
Note: 1. Tuning of the PA BIAS must be performed first.
2. This procedure must be performed before tuning the transmitter power.
3. If any of the DAC values exceeds the range 20-200 or the value of DAC1 is greater
than the value of DAC2, a warning message will be displayed.
4. The DAC values will only be updated when the radio is keyed up. If the radio is
not keyed up, any DAC value change will be ignored.
DAC1 DAC2
30-40W 70-80W