DRAKE 1002366 Manuel

Bilgisayar Donanımı DRAKE 1002366 için çevrimiçi göz atın veya pdf Manuel indirin. DRAKE 1002366 4 sayfaları. Packet processing/asi ts output option board

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Model 100-2366 Packet Processing/ASI TS Output Option Board (SCT860)

INTRODUCTION

The 1002366 board is used to process the

transport stream after satellite demodula-

tion and before QAM modulation. It

enables the FIXED CLOCK mode of

operation (AUTO CLOCK mode is still

selectable), performs PCR correction, and

it also provides an ASI output of the

demodulated transport stream.

TRANSPORT STREAM PROCESSING

The transport stream processing feature

of the 1002366 board will add null packets

if the SCT860 is set to the FIXED CLOCK

mode and the demodulated transport

stream data rate is less than the rate set

as the fixed output rate. The 1002366 can

also drop extra null packets from the

transport stream when required to obtain

the desired output rate.

The standard SCT860 does not modify the

transport stream - Drake labels this mode

the 'AUTO CLOCK' mode as the output

rate is automatically determined by the

received input signal data rate. When the

SCT860, with the 1002366 installed, is set

to the AUTO CLOCK mode setting, it

operates as if the board were not installed;

the null packets will not be processed and

neither dropping or adding will occur.

The 1002366 option board must be

installed into the SCT860, and the

SCT860 firmware must be updated, in

order to activate the FIXED CLOCK mode.

The null packet processing functions are

enabled in the FIXED CLOCK mode. The

AUTO CLOCK mode can still be selected

in the menu.

When the SCT860, with the1002366

board, is set to the FIXED CLOCK

setting, all null packets will be dropped

from the demodulated transport stream.

The rate is then built back up, by adding

null packets, to the fixed output QAM

symbol (baud) rate that is set via the front

panel. Dropping null packets is required in

some cases in order to bring the rate

down to or below the desired rate when

the satellite uplink may add extra null

packets.

PCR CORRECTION

The SCT860 performs PCR correction on

the processed transport stream before

QAM modulation when the SCT860 is

used with the 1002366 option and is set

up in the FIXED CLOCK mode. No PCR

adjustments are made when the unit is set

to the AUTO CLOCK mode.

ASI OUTPUT

The 1002366 option board also adds an

ASI transport stream output connector to

the SCT860. A chassis mount type BNC

connector with coaxial cable is provided

for those who have a requirement for this

feature. The ASI output will be the de-

modulated satellite signal transport stream

output, without processing. It is provided in

DVB ASI format.

This output may be used to feed the

satellite signal transport stream to a

multiplexer where part of the stream may

be needed for remultiplexing with another

stream for another output channel.

If ASI output is not a requirement, place

the connector assembly in a storage

location for possible future use.

If the ASI output feature is desired, plug in

the supplied BNC connector cable to the

SCT860 PC board as indicated in Figure 3

and mount the BNC connector in the rear

panel mounting hole. If your SCT860

does not have this hole, it must be added.

The unit can be returned to the Drake

Service Department, if necessary, for this

installation.

INSTALLATION IN THE SCT860

Looking at the SCT860 from the front panel,

observe the right side of the unit.

Remove the three top screws as shown,

three side screws, and three bottom screws

holding the right side of the case.

Remove the right side and then lay the

transcoder on a flat surface laying on its left

side.

Locate the 36 pin interface connector and

remove the 11 jumpers that are in place.

Keep these jumpers for future use in case

the 100-2366 board is ever removed.

REMOVE 11 JUMPERS FROM THE 36 PIN CONNECTOR

LOCATION A

Installation

3 TOP SCREWS