User's Manual

MTR3000 Programming and Tuning: Modulation Limit Alignment 12-7
6. De-key the radio.
The deviation shall meet the limits shown in the table below.
12.5.3 Tuning Procedure (with Tx Data or PL)
1. Connect the radio’s antenna port to the attenuation pad, if necessary, before connecting to
the Communication Analyzer.
2. Turn on the Station using an AC or DC source.
3. Click the “Read” button on the Tuner application to read the radio’s softpot values.
4. Select “Modulation Limit” under the Tx menu in the tree view.
5. Enter the tuning frequency into the Communication Analyzer (the value displayed by the
Tuner application).
6. Click the “PTT Toggle” button within the Tuner environment to key up the radio.
7. Apply a 1 kHz signal at 1.2Vrms to Pin 22 of the J7 backplane connector.
- Signal ground is Pin 9 of the J7 backplane connector.
- If the manufacturer of the third party controller specifies that the Tx Audio is not to be pre-
emphasized, use Pin 1 instead of Pin 22.
8. Adjust the Modulation Limit softpot to a value that limits the maximum deviation to “X”% RSD,
where “X” is equal to “92% RSD” minus “Tx Data’s % RSD”.
E.g. If Tx Data deviation is equal to 17%,
X = 92% - 17% = 75% as the maximum deviation limit.
Figure 12-7. Example of maximum deviation limit calculation
9. Click the “PTT Toggle” button within the Tuner environment to de-key the radio.
Channel Spacing
Relative
Standard
Deviation
(RSD)
92% of RSD Tolerance
12.5 kHz 2.5 kHz 2.3 kHz +0Hz / -50Hz
20.0 kHz 4.0 kHz 3.68 kHz +0Hz / -80Hz
25.0 kHz 5.0 kHz 4.6 kHz +0Hz / -100Hz
Note The BR will be factory-tuned in accordance to the above procedure and specification.
8%
17%
75%
100%
0%
%RSD
92%
With Tx Data or PL
Buffer
Data or PL
Voice
Applicant: Motorola
Equipment Type: ABZ89FC4827
Exhibit D1-4