6 General Description / Installation and Mounting
OBM100 DESCRIPTION
The OBM100 is an out of band data modulator for use with
the SCT2X4 headend satellite to cable transcoder. The
purpose of the OBM100 is to provide a one way data
channel from the headend to a universe of set top boxes that
are being served by the headend. Usually program guide
and conditional access control information will be sent
through this channel.
The OBM100 provides two functions in the data manage-
ment process. First of all it accepts an ASI transport stream
from the SCT2X4 data output connector. This is data that is
sent over the satellite path to the headend. The OBM100
takes this low data rate stream and without making any
changes to the data, outputs the data through an Ethernet
connection to the headend control PC.
After the headend PC constructs a complete data stream for
the set tops, derived from the satellite delivered data and
from locally generated data, the resulting stream is output
from the headend control PC back to the OBM100 on the
same Ethernet cable that is passing the satellite delivered
data in the other direction. The OMB100 accepts this incom-
ing data and performs its second function – transmitting this
data stream to the set top boxes.
The OBM100 generates a QPSK modulated signal, modu-
lated by the data stream from the headend controller, at a
data rate of approximately 3 Mbps. This signal is upconverted
to any operator selected frequency between 70 and 130 MHz
for transmission throughout the cable plant.
INSTALLATION AND MOUNTING NOTES
This equipment is designed to be installed in a standard 19”
rack. When the unit is mounted above or below other rack
mounted equipment, a 1U space (1.75”) should be left
between the unit and the other equipment to allow ambient
air flow between the units.
Connect a cable from the OBM100 Ethernet connector to the
Ethernet connector on the PC based headend controller.
Connect each of the four ASI INPUT connectors of the
OBM100 to the ASI DATA connectors of the Drake SCT2x4
Transcoders in the system.
Connect the OBM100 RF OUTPUT connector to the output
combiner which sends downstream RF.
Connect the AC line cord to an appropriate source of 120
volt, 60 Hz AC power. The OBM100 is always on once the
AC power cord is connected to its power source.
TYPICAL Drake BBT HEADEND INSTALLATION
ENTER
OBM100 QPSK DATA MODULATOR
DHCP............
OBM100 1.4
RS2 32 in
Drake S CT 2X4
RF Out 4 QAM C hannel s
S at ellit e to Q AM
Tra nscoder
Drak e
RS2 32 in
Drake S CT 2X4
RF Out 4 QAM C hannel s
PC12 01
S at ellit e to Q AM
Tra nscoder
12 w ay
Avai l Me dia/ BBT
RS2 32 in
Tra ns port
Drake S CT 2X4
RF Out 4 QAM C hannel s
Combine r
S at ellit e to Q AM
Tra nscoder
To Subs cri bers
RS2 32 in
Drake S CT 2X4
RF Out 4 QAM C hannel s
S at ellit e to Q AM
Tra nscoder
ASI Data out
Head-end Controll er
PC Based
E the rnet
E the rnet
Data
Contr ol Data
Drak e OBM100
Drak e DQT1000
2 56 QAM out
2 8VS B to 1 Q AM
RS2 32 in
Drak e DQT1000
2 56 QAM out
2 8VS B to 1 Q AM
RS2 32 in
12 NTS C inputs
Analog to D igi ta l E H24
up to 1 2 M P EG2 /4 programs out at 64 or 25 6 QAM
6 dual M PEG Enc oders
RS2 32 in
IP conne ction
SCTe ci IP Controlle r
RS2 32 out
RF OUTPUT
ASI INPUTS
RS232
ETHERNET
120 VAC 60 Hz
10 WATTS
AC POWER
1
2
3
4
OUT OF BAND MODULATOR
OBM100
MAC ADDRESS
*0000000000000000*
