DRAKE SCT2860 Руководство по эксплуатации - Страница 5

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General Description / Installation and Mounting

GENERAL DESCRIPTION

The R.L. Drake model SCT2860 is a

professional quality, modular, digital headend component

providing QPSK or 8PSK input to QAM transmodulation

and RF upconversion functions in a single module. Up to

ten SCT2860 modules and a power supply module can be

accommodated in the RMT150 rack mounting tray,

occupying only a 2 unit (3.5") high rack space. The

SCT2860 can transcode DigiCipher II or DVB digital

satellite signals, included those with advance turbo

satellite FEC modes, outputting QAM modulation.

The SCT2860 accepts L band RF inputs between 950 and

2150 MHz from the LNB at the satellite dish. The Drake

LBS2250 may be used to allow switching between two

LNB feeds and to also provide output combining for up to

10 SCTs. The transcoder demodulates and error

corrects the selected satellite QPSK or 8PSK signal.

INSTALLATION AND MOUNTING

Install the SCT2860 transcoders in the RMT150 rack

mounting frame. Slide each module into the tray so that

the "F" connector extends though the front panel hole, the

LED is properly aligned behind its front panel hole, and

the hook shaped projection on the rear of the module

engages the rear of the mounting tray. Secure the module

with the supplied standard 1/2 inch "F" connector mount-

ing nut.

Similarly, mount the PS151 power supply in the RMT150

tray, making sure that the LCD display and control buttons

line up with their corresponding holes in the front panel,

and that the hook shaped projections on the rear of the

unit engage the rear of the mounting tray. Secure the unit

in place, with the supplied Philips head black screws, from

the front panel. Connect each SCT2860 to the PS151

with the cable included with the SCT2860. Each SCT2860

can connect to any one of the ten sockets on the power

supply. However, to minimize confusion, it is suggested

that the left most unit (as viewed from the front panel) be

connected to power supply socket number 1, the second

from the left to number 2, etc.

RS232 OUT

RS232 IN

+12

GND

FAN POWER

100 - 240 VAC

47 - 63 HZ, 125 W

L BAND INPUTS

RF OUTPUT

POWER

The transcoder then applies cable environment FEC to

this stream and remodulates using QAM modulation that

occupies a nominal 6 MHz wide cable channel slot.

The RF upconverter then upconverts the IF QAM signal to

the selected output channel - any standard EIA, IRC, or

HRC CATV channel or a broadcast off-air channel

frequency in the range of 54 to 860 MHz.

Bandpass flatness and phase noise are closely controlled

in the SCT2860 to insure a high MER and S/N ratio of the

output signal. This insures that the transcoder will not

introduce a source of errors into the distribution process.

Because the MPEG2 transport stream information is not

modified by the transcoder, all encryption, authorization,

and program guide information is passed on to the CATV

set top box, unchanged.

Connect the LNB signal from the LNB splitter to each

SCT2860 module at the front panel connector. Connect

each SCT2860 RF output "F" connector on the rear of the

unit to the output combiner. Plug the cable from the front

panel fan module into the FAN POWER receptacle on the

rear of the power supply. Plug the line cord from the

PS151 into the AC power source.

When installing the RMT150 tray of transcoders, it is not

necessary to leave a vertical airspace between the

transcoder tray and other equipment unless that other

equipment specifies that a space should be left open. The

air flow through the transcoders and power supply has

been designed to allow immediate adjacent mounting of

multiple RMT150 trays with SCT2860 transcoders and

PS151 power supplies installed. Of course, air spaces

may be left in between RMT150s if desired.

RF OUTPUT

POWER

DRAKE TRANSCODER SYSTEM

1.1

12.45 dB

UNIT

SELECT

ENTER

RF OUTPUT

POWER