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Rack-Mount RDMS
TM
Telemetry Receiver
30
Quasonix, Inc.
If Modulation Scaling is set to Locked, as shown in Figure 37, the active modulation scale index is also locked in on
a particular setting. The modulation scale index number displays next to the Locked setting.
If an index number was entered manually using the Mod Scale Index option (on the Mod Scaling Menu),
Modulation Scaling is simultaneously changed to Locked and reflects the Index value set via the Mod Scaling
Menu.
Locked index numbers, manually or automatically selected, are lost when the Mod Scaling option is set to Tracking,
Off, or Acquire. If the Locked index number is to be retained following a power-off cycle of the rack, then turn on
the Mod Persist option via the Main Menu. Refer to section 4.1.4.11, Modulation Persistence.
4.1.4.10.3 Modulation Scaling - Off
The Mod Scaling Off setting is shown in Figure 39. When Modulation Scaling is set to Locked, the graphing eye
pattern is displayed in green, indicating the optimal modulation index is set.
Figure 39: Main Menu, Modulation
Scaling
– Off
Figure 40: Green Eye Pattern Display
- Off
With Mod Scaling turned Off, the Mod Index is set to the optimal 0.700. Mod Scaling should be turned off when a
new generation, digitally synthesized transmitter is the source. Digitally synthesized transmitters do not have a
variable deviation sensitivity adjustment, and as such are not subject to inaccurate modulation index settings
4.1.4.10.4 Modulation Scaling - Acquire
Acquire mode has two states: Armed and Triggered. When Modulation Scaling is set to Acquire, in the absence of
signal, the eye pattern will turn yellow, as shown in Figure 42, the state is set to Armed. In Armed state, modulation
scaling operates continuously.