Motorola Cdm Series Basic 6881091c62 D Manual

							Radio Programming and Tuning Procedures4-9
4.4.7 VCO Attenuation
Table 4-6: Deviation Specifications for UHF/VHF/LowBand Radios*
*These values are up-to-date as of the print date. For the latest values and procedures, refer to the 
Tuner online help.
4.4.8 VCO Attenuation (25 kHz)
Perform the 25 kHz VCO attenuation procedure as follows:
1. Under the Tx Align menu, select VCO Attn. 25 kHz.   
2. Begin with the lowest frequency.   Select the thumb of the slider at the lowest frequency point, 
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 the selection. 
3. Inject 1 kHz at 800mVrms to the external microphone audio path.Note:
1.  Tuning of the modulation balance must be accomplished first. The transmit devi-
ation Limit softpot sets the maximum deviation of the carrier. Tuning is performed 
for 12.5 kHz, 20 kHz, and 25 kHz channel spacing. Tuning for 25 kHz channel must 
be done first for all frequency points. Tuning for 12.5 and 20 kHz channel spacing 
determines only the offset to the previously tuned deviation for 25 kHz tuning 
channel spacing. For 12.5, 20 kHz channel spacing, only F7 is used for tuning. 
The 30 kHz channel spacing which uses 5.0 kHz maximum system deviation are 
covered by the 25 kHz tuning.
2.  When using test box RLN4460, set the METER OUT toggle switch to the “MIC 
PORT” position and METER OUT selector switch to “MIC”. Inject 1 kHz tone, and 
800mVrms to AUDIO IN. The 800mVrms should be measured at the AC/DC 
METER.
3.  Depending on the radio model and the customer settings, the signal injected in 
accessory connector Pin 5 or the signal from an option board may be transmitted 
simultaneously with other signals, for example from the microphone or internally 
generated signaling. In this case the peak signal level is the sum of the individual 
signals peak levels and can exceed the maximum allowed transmit deviation 
level. To prevent over deviation, the maximum deviation must be measured with 
both signals present and if the deviation still exceeds the range defined in Table 
4-6, the VCO Attenuation must be re-tuned, so that the deviation stays in the tun-
ing range with both signals present.
4.  Tuning of the modulation balance attenuation must be performed first.
Band Channel SpacingRated System 
DeviationDeviation (kHz)
UHF/VHF/LowBand25 kHz5 kHz4.4 – 4.6
LowBand (20 kHz sys-
tems in North America)20 kHz 5 kHz 4.4 – 4.6
UHF/VHF20 kHz4 kHz3.4 – 3.6
UHF/VHF/LowBand 12.5 kHz 2.5 kHz 2.2 – 2.3 
						

							4-10Radio Programming and Tuning Procedures
4. Note the deviation obtained.
5. Adjust the slider, adjust the spin control or key in softpot values for the frequency point until the 
deviation is within the range as defined in the Table 4-6 on page 4-9. Press ENTER to confirm the 
selection.
6. Press the PTT Toggle button to dekey radio. Choose the next frequency, key up, then repeat 
Steps 3-5 until all seven tuning points are completed.
7. Program the softpot value by pressing the Program button.
8. Exit the VCO attenuation 25 kHz function.
4.4.9 VCO Attenuation (20 kHz)
Perform the 20 kHz VCO attenuation procedure as follows:
1. Under the Tx Align menu, select VCO Attn. 20 kHz.
2. Press PTT Toggle to key up the radio at F7.
3. Inject 1 kHz at 800mVrms to the external microphone audio path.
4. Note the deviation obtained.
5. Adjust the slider, adjust the spin control or key in softpot values for the frequency point until the 
deviation is within the range as defined in Table 4-6 on page 4-9. Press ENTER to confirm the 
selection.
6. Press PTT Toggle to dekey the radio.
7. Program the softpot value by pressing the Program button.
8. Exit the VCO attenuation 20 kHz function.
4.4.10 VCO Attenuation (12.5 kHz)
Perform the 12.5 kHz VCO attenuation procedure as follows:
1. Under the Tx Align menu, select VCO Attn. 12.5 kHz.
2. Press PTT Toggle to key up the radio at F7.
3. Inject 1 kHz at 800mVrms to the external microphone audio path.
4. Note the deviation obtained.
5. Adjust the slider, adjust the spin control or key in softpot values for the frequency point until the 
deviation is within the range as defined in the Table 4-6. Press ENTER to confirm the selection.
6. Press PTT Toggle to dekey the radio.
7. Enter the softpot value into the radio by pressing the Program button.
8. Exit the VCO attenuation 12.5 kHz function.Note:
Tuning of modulation balance attenuation and VCO attenuation for 25kHz channel 
spacing must be accomplished first.
Note:
Tuning of modulation balance attenuation and VCO attenuation for 25kHz channel 
spacing must be accomplished first. 
						

							Radio Programming and Tuning Procedures4-11
4.4.11 DTMF Deviation Tuning
This tuning option controls the dual-tone, multi-frequency (DTMF) deviation. 
Perform the DTMF deviation tuning procedure as follows:
1. Under the Tx Align menu, select DTMF Deviation.
2. Press PTT Toggle to key the radio up. Monitor the deviation obtained.
3. Adjust the slider, spin, or edit control until a deviation of 3.1-3.4 kHz is obtained. Press ENTER to 
confirm the selection.
4. Press PTT Toggle again to dekey the radio.
5. Program the softpot value into the radio by pressing the Program button.
6. Exit the DTMF deviation function.
4.4.12 MDC1200 Deviation Tuning (MDC radios only)
This tuning option controls the MDC1200 Signaling deviation. 
Perform the MDC1200 deviation tuning procedure as follows:
1. Under the Tx Align menu, select MDC1200 Signaling.
2. Press PTT Toggle to key the radio up. Monitor the deviation obtained.
3. Adjust the slider, spin or edit control until a deviation of about 3.3 – 3.7kHz is obtained. Press 
ENTER to confirm the selection.
4. Press PTT Toggle again to dekey the radio.
5. Program the softpot value into the radio by pressing the Program button. 
6. Exit the MDC1200 deviation function.
4.5 Receiver Tuning
The following sub-sections contain the procedures to tune the radio receiver. These procedures 
include: 
lFront End Filter Tuning
lRated Volume
lSquelch Tuning Front End Filter Tuning Note:
Modulation balancing and VCO attenuation must be performed prior to this tuning 
operation. Not doing so will result in the wrong deviation value being obtained while 
tuning the DTMF.
Note:
Modulation balancing and VCO attenuation tuning must be performed prior to this 
tuning operation. Not doing so will result in the wrong deviation value being obtained 
while tuning this feature. 
						

							4-12Radio Programming and Tuning Procedures
4.5.1 Front End Filter Tuning
The following values in Table 4-7 through Table 4-12 are up-to-date as of the print date. For the latest 
values and procedures, refer to the Tuner online help.Note:
1.  Tuning is normally not required. It should only be performed if a radio has poor 
sensitivity or pre-selector parts have been replaced. Radios are only tuned at one 
softpot frequency (See Table 4-7 through Table 4-12). The values for the untuned 
frequencies are determined by adding the offset, calculated by subtracting the 
default softpot value for tuned frequency from the tuned softpot value for the 
tuned frequency. 
2.  When using the test box RLN4460, measure the RSSI voltage with a DC voltmeter 
connected to the METER OUT terminals of the test box. Select “DISC” on the 
METER OUT rotary switch.
3.  Tuning is only performed for 25kHz channel spacing. 
4.  Warping of the reference oscillator must be accomplished first.
5.  LowBand radios do not require tuning of the front end filter.
Table 4-7: Default Softpot Values for VHF (136-174 MHz)
Frequency Point Softpot Value (Decimal)
F145
F2 56
F366
F4 76
F585
F6 95
F7102
Table 4-8: Default Softpot Values for UHF (403-470 MHz/ 25W)
Frequency Point Softpot Value (Decimal)
F143
F2 49
F357
F4 63
F567
F6 77
F789 
						

							Radio Programming and Tuning Procedures4-13
Table 4-9: Default Softpot Values for UHF (403-470 MHz/ 40W)
Table 4-10: Default Softpot Values for UHF (450-512 MHz/ 40W)
Table 4-11: Default Softpot Values for UHF (450-512 MHz/ 25W - VMOS)
Frequency Point Softpot Value (Decimal)
F163
F2 67
F375
F4 77
F581
F6 91
F7101
Frequency Point Softpot Value (Decimal)
F161
F2 65
F371
F4 85
F595
F6 101
F7109
Frequency Point Softpot Value (Decimal)
F161
F2 65
F371
F4 83
F595
F6 101
F7107 
						

							4-14Radio Programming and Tuning Procedures
Table 4-12: Default Softpot for UHF (450-512 MHz/ 25W - LDMOS)
Perform the front end filter tuning procedure as follows:
1. Under the Rx Align menu, select the Front End Filter option.
2. Select the thumb of the slider of the frequency point given under “Frequency Point” for the radio’s 
frequency band from one of the Table 4-7 through Table 4-12. 
3. Inject a -87dBm RF signal with the frequency selected in Step 2, modulated with 1kHz tone at 
60% rated deviation of values listed in Table 4-13. A 1kHz tone must be audible to make sure that 
the radio is receiving. Switch off the modulation.
4. Set the softpot to the start value given specified in one of the Table 4-7 through Table 4-12 by 
adjusting the slider, keying in the softpot values in the edit box (press ENTER to confirm the 
selection) or using the spin control.
5. Measure the RSSI voltage with a DC voltmeter capable of 1mV resolution. It is recommended that 
an RCA filter (1.5K-47uF) be added at the input of the voltmeter to reduce RSSI noise. Call this 
V1.
6. Change the softpot value by the “Step Value” specified in one of the Table 4-7 through Table 4-12. 
A positive step value must be added, while a negative value must be subtracted from the current 
softpot value. Call this SP.
7. Re-measure the RSSI voltage. Call this V2.
8. Calculate the RSSI voltage change in percent using the formula 100* (V2/V1-1). If the calculated 
value is negative or lower than the target value given from one of the Table 4-7 through Table 4-
12, continue with Step 9. Otherwise repeat Steps 6 through 8.
9. Calculate the softpot offset using formula SP – Default SP. For Default SP, use the default 
softpot value specified in Table 4-7 through Table 4-12 for the tuning frequency given in Table 4-
14. Add the calculated offset to all default values given in the table for the radio’s frequency range 
and enter the results in the edit boxes for the appropriate softpot frequencies.
10. Program the softpot values into the radio by pressing the Program button.
11. Exit the front end filter tuning function.
Frequency Point Softpot Value (Decimal)
F153
F2 59
F365
F4 73
F575
F6 79
F787 
						

							Radio Programming and Tuning Procedures4-15
*These values are up-to-date as of the print date. For the latest values and procedures, refer to the 
Tuner online help.
4.5.2 Rated Volume Tuning
Perform the rated volume tuning procedure as follows:
1. Under the Rx Align menu, select Rated Volume.
2. Inject a -47dBm rf signal modulated with 1 kHz tone at the 60% rated deviation listed in Table 4-
15.
3. Adjust the softpot value by using the slider, keying in the edit box (press ENTER to confirm the 
selection or send a softpot value), or via the spin controls. Repeat this until 3W(8Vrms) audio 
power is obtained. Press Program to commit the softpot value into the radio.
4. Exit the rated volume tuning function.Table 4-13: Front End Filter Deviation Values
Channel SpacingRated System 
DeviationSignal Generator 
Deviation
12.5 kHz2.5 kHz1.5 kHz
20 kHz 4.0 kHz 2.4 kHz
25 kHz5.0 kHz3.0 kHz
30 kHz 5.0 kHz 3.0 kHz
Table 4-14: Front End Tuning Parameters*
RF Band Frequency Point  RF Level Start Value Step Value Target Value
UHF (403-470 
MHz) (40W)F1-87dBm69-20.17% of RSSI 
Vo l ta g e
UHF (403-470 
MHz) (25W)F1 -87dBm 61 -2 0.17% of RSSI 
Vo l ta g e
UHF (450-512 
MHz)F4-87dBm85-20.20% of RSSI 
Vo l ta g e
UHF (450-512 
MHz) (LDMOS)F4 -87dBm 85 -2 0.20% of RSSI 
Vo l ta g e
VHF (136-174 
MHz)F4-87dBm64+30.17% of RSSI 
Vo l ta g e
Note:
When using test box RLN4460B/C, the received audio output is taken from the AC/DC 
METER OUT terminals with the METER OUT rotary switch set to RX. 
						

							4-16Radio Programming and Tuning Procedures
4.5.3 Squelch Tuning
Perform the squelch tuning procedure as follows:
1. Under the Rx Align menu, select Squelch Atten. Select either Squelch Atten 12.5 kHz, 
Squelch Atten 20 kHz or Squelch Atten 25 kHz channel spacing variations. 
2. Apply an RF signal modulated with a 1 kHz tone at 60% rated deviation listed in Table 4-16 for 
current frequency point (F1 being the first) of 10dB SINAD. That is, adjust the reference signal 
level until 10dB SINAD is obtained at the SINAD meter. Squelch tuning can either be done 
manually (see page 17 for procedure) or by auto squelch (see page 17 for procedure). To obtain 
10dB, unmute the radio first by dragging the corresponding slider value to 1. Table 4-15: Rated Volume Deviation Values
Channel Spacing Rated System Deviation Signal Generator Deviation
12.5 kHz2.5 kHz1.5 kHz
20 kHz 4.0 kHz 2.4 kHz
20 kHz (LowBand 20 kHz 
systems in North America)5.0 kHz3.0 kHz
25 kHz 5.0 kHz 3.0 kHz
30 kHz5.0 kHz3.0 kHz
Note:
1.  Squelch tuning can only be accomplished after front end filter tuning and refer-
ence oscillator warping.
2.  When using the test box RLN4460, the received audio output is taken from the 
AC/DC METER OUT terminals with the METER OUT rotary switch set to RX. It is 
recommended that rated volume tuning is performed so the correct 10dB SINAD 
level can be obtained.
3.  This tuning method is performed for multiple squelch tuning channels and multi-
ple channel spacings.
Table 4-16: Squelch Deviation Values
Channel Spacing Rated System Deviation Signal Generator Deviation
12.5 kHz2.5 kHz1.5 kHz
20 kHz 4.0 kHz 2.4 kHz
20 kHz (LowBand 20 kHz 
systems in North America)5.0 kHz3.0 kHz
25 kHz 5.0 kHz 3.0 kHz
30 kHz5.0 kHz3.0 kHz 
						

							Radio Programming and Tuning Procedures4-17
Manual Squelch Tuning:
1. Under the Rx Align menu, select Squelch Atten. Select either Squelch Atten 12.5 kHz, 
Squelch Atten 20 kHz or Squelch Atten 25 kHz channel spacing variations. 
2. Apply an RF signal modulated with a 1 kHz tone at 60% rated deviation listed in Table 4-16 for 
current frequency point (F1 being the first) of 10dB SINAD. That is, adjust the reference signal 
level until 10dB SINAD is obtained at the SINAD meter. Squelch tuning can either be done 
manually (see page 17 for procedure) or by auto squelch (see page 17 for procedure). To obtain 
10dB, unmute the radio first by dragging the corresponding slider value to 1.
3. Set softpot to its maximum value to mute the radio.
4. Adjust the softpot value by using the slider, keying in the edit box or using the spin controls. Press 
ENTER to confirm the selection. Do this until the radio is totally unmuted. Verify the squelch 
closing by inputting a signal level of 4dB lower than that of the 10dB SINAD level.
5. Repeat Step 2 and Steps 3-4 of Manual Squelch Tuning, for frequency points F2-F7.
6. Press Program to commit the softpot values into the radio.
7. Exit the squelch tuning function.
Auto Tune:
When you press the Auto Tune button, the radio automatically returns an optimum squelch value.
After you press the button, the radio may need time to produce an optimal setting for the squelch 
attenuation. The following steps describe the auto tune process:
Auto Tuning:
1. Under the Rx Align menu, select Squelch Atten. Select either Squelch Atten 12.5 kHz, 
Squelch Atten 20 kHz or Squelch Atten 25 kHz channel spacing variations. 
2. Apply an RF signal modulated with a 1 kHz tone at 60% rated deviation listed in Table 4-16 for 
current frequency point (F1 being the first) of 10dB SINAD. That is, adjust the reference signal 
level until 10dB SINAD is obtained at the SINAD meter. Squelch tuning can either be done 
manually (see page 17 for procedure) or by auto squelch (see page 17 for procedure). To obtain 
10dB, unmute the radio first by dragging the corresponding slider value to 1.
3. Select current frequency point (F1 being the first), then press Auto Tune.
4. Repeat Steps 2 and 3 of the Auto Tune section for frequency points F2-F7.Note:
Proceed with caution since this procedure automatically programs the softpot value 
into your radio. 
						

							4-18Radio Programming and Tuning Procedures
Notes