Motorola Astro Digital Spectra Digital Spectra Plus Basic 6881076c20 E Manual

6881076C20-EFebruary 3, 2003
Radio Alignment Procedure: RSS6-7
8. Press F10 once to return to the TRANSMITTER ALIGNMENT MENU, or press F10 twice to 
return to the SERVICE MENU.
6.2.6 Transmit Deviation Balance (Compensation) Alignment
NOTE:Compensation alignment is only required after replacing (or servicing) the command board, 
VOCON (vocoder/controller) board, RF board, or the VCO board.
Compensation alignment balances the modulation sensitivity of the VCO and reference modulation 
(synthesizer...

February 3, 20036881076C20-E
6-8Radio Alignment Procedure: RSS
Figure 6-7.  Transmit Deviation Balance (Compensation) Alignment Screen
5. Press Ta b to select and start the alignment at the lowest frequency listed.
6. Press F3 (TOGGLE LOW TONE PTT) to key the radio. Wait approximately five seconds until 
the frequency displayed on the analyzer stabilizes.
7. Measure and record the deviation value from the 8901_ analyzer or the ac voltage value from 
the R-2670 analyzer.
8. Press F3 to dekey the radio.
9....

6881076C20-EFebruary 3, 2003
Radio Alignment Procedure: RSS6-9
- In the “RF Control” section of the R-2670, enter the frequency displayed on the RSS screen 
(choose a test frequency from the list of frequencies displayed under TRANSMIT 
DEVIATION LIMIT screen in RSS). Move the cursor to the “B/W” setting and select “WIDE 
+/- 100 kHz” via the soft key menu.
- Place the R-2670 cursor in the “Display” zone. Move the cursor to the “Meter” setting and 
select “AC VOLTS” via the soft key menu. Move the cursor...

February 3, 20036881076C20-E
6-10Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software
6.2.8 Bit Error Rate (BER) Performance Check
This check tests the Bit Error Rate (BER) of the radio’s receiver at a desired frequency.
Required equipment and software: R-2670 system analyzer, with P25 option; IBM PC-compatible 
computer, RSS
In Generate mode, the R-2670 system analyzer modulates the RF carrier with a 1011Hz tone test 
pattern to test the Unit Under Test (UUT)...

6881076C20-EFebruary 3, 2003
Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software 6-11
Figure 6-9.  ASTRO Digital Spectra Plus Radio Alignment Test Setup
Select Tuner from the START menu. To read the radio, use the File 
➝ Read Device menu or click 
on . 
Figure 6-10 illustrates how the alignment screens are organized. To access a screen, 
double-click on the desired screen name in the Tuner menu. These procedures should only be attempted by qualified 
service...

February 3, 20036881076C20-E
6-12Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software
Figure 6-10.  Tuner Menu Layout
The alignment screens introduce the concept of the “softpot,” an analog SOFTware-controlled 
POTentiometer used for adjusting all transceiver alignment controls.
Each alignment screen provides the ability to increase or decrease the softpot value by using the 
slider or the screen’s spin buttons (
▲ and ▼), or by entering the new value from the...

6881076C20-EFebruary 3, 2003
Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software 6-13
Figure 6-11.  Typical Softpot Adjustment Screen
Adjusting the softpot value sends information to the radio to increase (or decrease) a voltage in the 
corresponding circuit. For example, left-clicking the UP spin button (
▲) on the Reference 
Oscillator screen instructs the radio’s microcomputer to increase the voltage across a varactor in 
the reference oscillator, which increases...

February 3, 20036881076C20-E
6-14Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software
6.3.1 Radio Information
Figure 6-12 shows a typical Radio Information screen. All of the data appearing here is informational 
and cannot be changed..
Figure 6-12.  Radio Information Screen
6.3.2 Reference Oscillator Alignment
Reference oscillator alignment is required after replacing (or servicing) the transceiver board.
Radios are shipped from the factory with a worst-case frequency...

6881076C20-EFebruary 3, 2003
Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software 6-15
- 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 8901_ Series Modulation Analyzer:
- Press the green Automatic Operation button on the analyzer. 
- Press the FREQ key.
- Type 7.1 followed by SPCL button to set the 8901_ modulation analyzer for...

February 3, 20036881076C20-E
6-16Radio Alignment Procedure: ASTRO Digital Spectra and Digital Spectra Plus Tuner Software
6. Left-click the Program (Digital Spectra) or Program All (Digital Spectra Plus) 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 Transmitter Alignments menu.
6.3.3 Transmit Power Alignment
Transmit Power alignment is required after replacing (or servicing) the transceiver board.
This alignment procedure...