DRAKE OBM100 Manuel d'instruction - Page 8

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Setup and Programming / Software Flow Chart

GENERAL

Programming and viewing of the various setup and operating

parameters are accomplished using the front panel back lit,

two line, sixteen character wide LCD along with the LEFT,

RIGHT, UP, DOWN and ENTER buttons. Generally, the name

of the parameter is on the top line of the display and the

setting value is on the bottom line. For some parameters,

both the parameter name and value are on the bottom line.

To observe a certain parameter setting without intending to

change its value, just use the LEFT and RIGHT arrow

buttons to navigate through the menus shown in the software

flow chart below. Generally, the current setting for each

parameter is shown on the bottom line of the display. Note

that depending upon certain settings, some screens are not

needed and will be skipped.

To make a change in the displayed parameter and its setting

and if this is the initial setup, you will want to enter the 'adjust'

mode. To do this, press the ENTER button that is located in

the center of the four arrow buttons and hold in for several

"^"

seconds until a flashing

corner of the display. After you are in the adjust mode, use

the LEFT and RIGHT arrow buttons to navigate among

screens and use the UP and DOWN arrows to change the

parameter setting.

When certain numerical values are to be adjusted, one or

more asterisks (

) will appear above the digits to be ad-

justed. Use the UP and DOWN keys to change the value

OBM100 1.4 c

Up & Down

DHCP...........

buttons in

DHCP...........

normal mode

only.

xxx.xxx.xxx.xxx

xxx Frames/S

to RF Output

xxx Frames/S

from ASI Input

Board Setup...

MAC xxxxxxxxxxxx

DHCP OFF

(Normal Mode)

SETTINGS

Frequency: Set the output frequency of the OBM100 as

required by the system map design. The frequency range is

from 70 to 130 MHz, adjustable in .05 MHz steps.

Output: Set the desired RF output signal level. The avail-

able range is from 30.0 to 52 dBmV in .5 dBmV steps. The

output accuracy is

± 1 dB.

OUTPUT MODE: For normal operation, select NORMAL.

For system level set up, choose CW to provide a CW carrier

at the center frequency of the output channel for use in

leveling a system when a QAM power meter is not available.

In the CW mode, the CW carrier can be measured on a

appears in the upper right hand

OBM100 QPSK DATA MODULATOR SOFTWARE FLOW CHART

Freq xxx.xx MHz

70 - 130 MHz

DHCP ON (Adjust Mode)

DHCP OFF

(Adjust Mode)

DHCP ON (Normal Mode)

SUBNET mask

GATEWAY addr

255.255.255.255

000.000.000.000 -

255.255.255.255

DHCP OFF

(Adjust & Normal Modes)

of the digit, and the LEFT or RIGHT keys to move to another

digit. Note that the astrisk(s) will not appear when scrolling

through adjustable parameters using the LEFT arrow key

unless it has already been activated using the RIGHT arrow

key.

When ENTER is pressed, the new settings will be loaded

and stored and the unit will exit the 'adjust' mode. You may

wish to not press ENTER until you have gone through all

screens and settings and then press ENTER to save and

load all changes in one step, OR you can store just one or

several parameters at a time and reenter adjust mode to set

the next. Either method is acceptable.

The OBM100 has displays that show the number of frames

per second that are input from the ASI inputs and are being

sent to the RF output. Each frame that comes from the ASI

inputs contains seven packets of 188 bytes each (1316

bytes). If a connection to the headend (as defined by the

destination address) has not been established through an

ARP reply, then the characters that display the number of

frames per second for the ASI input is replaced with a "NC"

display.

The frames being sent to the RF output contain between one

and seven packets of 188 bytes, depending upon what is

being sent to the OBM100 from the headend controller. The

headend controller will need to send frames with seven

packets in each frame to allow the unit to function properly

when high data rates are being sent through the RF output.

Output

Mode

30.0 - 52.0 dBmv

NORMAL

PRBS

IP addr

DHCP

enable

255.255.255.255

000.000.000.000 -

OFF

255.255.255.255

spectrum analyzer without a need to apply a bandwidth

correction or it can be measured with an analog meter tuned

to channel center. The CW power measured will equal the

channel QAM power when the modulator is returned to

normal output mode. Usually QAM signals are set 5 dB

below analog NTSC channels when balancing a system.

The PRBS menu entry is used for testing purposes only and

should normally not be selected by the user.

Symbol Rate: This setting allows selection of the output

symbol rate. Set as required by the set top boxes. The

choices are .772, 1.024, and 1.544 MHz.

Dest MAC

Symbol Rate

FFFFFFFFFFFF

.772

000000000000 -

1.024

FFFFFFFFFFFF

1.544

(Not User Settable)

Dest addr

Dest Port 65535

255.255.255.255

000.000.000.000 -

00000 -

65535

255.255.255.255