General Dynamics CG-1220, Operation And Maintenance Manual

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Operation
CG-1220 DTR 4-11

SLAVE ADDRESS is the address of this unit (a slave, controlled) on the
multi-drop RS-485 bus. There are a maximum of 32 addresses, ranging
from 0 to 31. On the bus, the actual ASCII value used for addressing is
the address assigned here plus the value of the parameter ADDRESS
OFFSET.

ADDRESS OFFSET is the offset added to the multi-drop bus address of a
device to determine the ASCII value needed to be used on the bus.
Example: ADDRESS-OFFSET is 48 (ASCII for '0')
MASTER-ADDRESS is 0
SLAVE-ADDRESS is 1
In the above example, the ASCII value on the RS-485 multi-drop bus
would be 48 (ASCII for '0') for the master, and 49 (ASCII for '1') for the
slave.

RESET PORT
resets the given port. The communication interface is
reinitialized and the shell (if any) that was running on it is restarted.
4.2.5.2 RECEIVER OPERATION
The
RECEIVER OPERATION configures how the Signal Processing Unit (SPU)
processes input signals.
- FILTERS controls the bandwidth of the band-pass filter, centered around the
receiver tuning frequency. A signal is detectable if it is visible on the spectral
display (MAIN\STATUS\SPECTRAL DISPLAY). A spectrum analyzer attached
to the IF Monitor port may be used to view the filter band. Filters 1 MHz and
narrower are centered at 70 MHz. Filters wider than 1 MHz are centered at 72
MHz, except 16 MHz. For the 16 MHz filter, the tuning frequency is translated
to 71 MHz; filter coverage is 9 MHz below to 7 MHz above. The 16 MHz filter
has a 1.5 MHz notch 7 MHz below the tuning frequency. To use this filter, the
NCO OFFSET should be zero (MAIN\CONFIGS\SYSTEM MEMORY\FACTORY
CALIBRATION\NCO OFFSET). In standard configurations choose from: 16 kHz,
32 kHz, 62.5 kHz, 125 kHz, 250 kHz or 500 kHz. In addition, wide-band units
provide these additional filters: 1 MHz, 2 MHz, 4 MHz, 8 MHz, 12 MHz, and
16 MHz.
500 kHz is the default bandwidth filter. This allows the ability to track most
CW beacon carriers. Selecting a smaller bandwidth filter will improve the
carrier-to-noise ratio (C/No). However, the bandwidth filter selected must be
greater than the Doppler Effect in order to track the carrier continuously.

ANALOG OUTPUTS - The ANALOG OUTPUTS menu controls the Digital to
Analog Converter (DAC) and contains the following items: