User Manual

SGD-SB2025NT-TUM, Part 1
Jan 12 Page 49 ALIGNMENT & TESTING
37.2. On the RTS, check that it is set to Auto tune or re-tune to the require frequency.
37.3. On the MxTools Channel screen, double click on the select channel to access the
Channel Edit screen.
37.4. On the Channel Edit screen, carry out the following:
37.4.1. Select the ‘Continuous Update Enabled’ tick box.
37.4.2. Set the ‘Ref Osc Level (LF Audio)’ digital potentiometer to value noted earlier
in Para 33.1.
37.4.3. Adjust the ‘VCO Level (LF Audio)’ digital potentiometer to obtain 1.5 kHz
deviation on the Radio Test Set.
37.4.4. Select the ‘OK’ button to accept the changes made and close the Channel Edit
screen.
37.5. On the MxTools Channel screen, on the dynamic tool bar, select ‘Write Channel’ button
to save the changes made to the radio.
38. Repeat Para 37 to Para 37.5 for all the configured channels.
39. On the NI ET, on the Engineering window, carry out the following:
39.1. On the Facilities tab, set the Test Tone ‘Frequency’ to 200 Hz.
39.2. Select the ‘Apply’ button.
40. On the Facilities tab, check that the Test Tone ‘Frequency’ has changed to ‘MOD’ indicating
that the SB2025 Modulation Balance test signal is being generated.
41. On the MxTools Channel screen, select one of the configured channels and carry out the
following:
41.1. On the MxTools Channel screen, select the ‘Set Software Channel To’ tick button.
41.2. On the RTS, check that it is set to Auto tune or re-tune to the require frequency.
41.3. On the RTS, use a Wide Band AF Filter setting with a response of at least 15 kHz and
monitor the SB2025 Tx modulation.
41.4. On the MxTools Channel screen, double click on the select channel to access the
Channel Edit screen.
41.5. On the MxTools Channel Edit screen, carry out the following:
41.5.1. Adjust the ‘Ref Osc Level (LF Audio)’ digital potentiometer so that the top and
bottom of the 200 Hz square wave displayed on the RTS is as flat as possible.
Note.
When making the adjustment in Para 41.5.1 above, only a small adjustment of the ‘Ref
Osc Level (LF Audio)’ control should be required to achieve the required square wave.
41.5.2. DO NOT adjust the ‘VCO Level (VF Audio)’ digital potentiometer.