Motorola PR400 - Manual (Page 43)

6881096C24-A August, 2004
Radio Alignment Procedures: Transmitter Alignment Options 5-9
5.4.4.1 VCO Attenuation 25 kHz
1. Under the Tx Align menu, select VCO Attenuation 25 kHz ( Figure 5-6 ).
2. Begin with the lowest frequency. Select the thumb of the slider at the lowest frequency point and
then press the PTT Toggle button to key up the radio at the corresponding frequency point. The
spin control can also be toggled via its up/down arrow buttons. The softpot value can also be
typed into the edit control (press ENTER to confirm your selection/send a softpot value).
3. Inject 1 kHz at an appropriate level until 2.3 V rms is measured at the AC/DC METER (radio
input) if using test box RLN4460.
4. Record the deviation obtained.
5. Adjust the slider; adjust the spin control or key in softpot values (press ENTER to confirm) for the
frequency point until the deviation is within the range specified in
Table 5-4 .
6. Dekey the radio (Press the PTT Toggle button). Choose the next frequency, key up and repeat
steps 3 to 6 until all seven tuning points are done.
7. Program the softpot value by pressing the Program button.
8. Exit the VCO Attn. 25 kHz function.
5.4.4.2 VCO Attenuation 12.5 kHz
1. Under the Tx Align menu, select VCO Attenuation 12.5 kHz.
2. Press PTT Toggle to key up the radio at the last non-0 transmit frequency point (normally F7).
3. Inject 1 kHz at an appropriate level until 2.3 V rms is measured at the AC/DC METER (radio
input) if using test box RLN4460.
4. Record the deviation obtained.
5. Adjust the slider, adjust the spin control or key in softpot values (press ENTER to confirm) for the
frequency point until the deviation is within the range specified in
Table 5-4 .
6. Press PTT Toggle to dekey the radio.
7. Program the softpot value by pressing the Program button.
8. Exit the VCO Attenuation 12.5 kHz function.
5.4.4.3 VCO Attenuation 20 kHz
1. Under the Tx Align menu, select VCO Attenuation 20 kHz.
2. Press PTT Toggle to key up the radio at the last non-0 transmit frequency point (normally F7).
3. Inject 1 kHz: at an appropriate level until 2.3 V rms is measured at the AC/DC METER (radio
input) if using test box RLN4460.
4. Record the deviation obtained.
5. Adjust the slider; adjust the spin control or key in softpot values (press ENTER to confirm) for the
frequency point until the deviation is within the range specified in
Table 5-4 .
6. Press PTT Toggle to dekey the radio.
7. Program the softpot value by pressing the Program button.
8. Exit the VCO Attn. 20 kHz function.
Note: Tuning of Modulation Balance Attenutation and VCO Attenuation for 25 kHz channel
bandwidth must be done first.
Note: Tuning of Modulation Balance Attn. and VCO Attn. for 25 kHz channel bandwidth
must be done first.