DRAKE ASII Buku Petunjuk - Halaman 12

Jelajahi secara online atau unduh pdf Buku Petunjuk untuk Modulator DRAKE ASII. DRAKE ASII 19 halaman. Hybrid qam modulator; digital tuner and demodulator module; encoder module; asi input module

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Setup and Programming, continued / Operation

INTERLEAVER: Sets the QAM modulator interleaver. Choose

among the available selections based upon your system / set top

box requirements. For typical 256-QAM. DigiCipher II CATV

systems, I128, J1 is the most commonly used interleave setting but

many other choices are available. This menu does not appear in

the adjust mode if the QAM mode is A (DVB) as there is only one

choice in the DVB standard. When not in adjust mode, this screen

will display the setting in QAM - A modes as well.

OUTPUT FORMAT: 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. To disable all RF output,

select STANDBY. In the CW mode, the CW carrier can be

measured on a 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 to 10 dB

below analog NTSC channels when balancing a system. The

PRBS modes provide a pseudo random binary sequence output

test signal for use in laboratory testing.

OUTPUT CHANMAP, OUTPUT CHANNEL: Select the desired EIA

CATV channel output using these two menus.

RF OUT: Select the desired RF output signal level. The available

range is between 45 dBmV and 62 dBmV, selectable in 0.5 dB

steps. The output accuracy is ± 1 dB.

SETUP: SDE24

SELECT: The LEFT and RIGHT buttons allow the user to scroll

through the encoder numbers for each encoder installed in the

MEQ1000 as well as the MEQ1000 itself. Use the LEFT and RIGHT

buttons to select the encoder to be programmed.

OPERATION - MULTIPLEXING TWO ATSC INPUTS

To use the DTD1000, SDE24 and/or the ASII modules to multiplex

two ATSC inputs, proceed as follows:

1) Connect the off-air antenna, CATV feed, or audio and video

(SDE24) or ASI feed, to the INPUT A and INPUT B inputs of the

MEQ1000. If using two RF inputs the two input connectors are

available in case the two RF signals must come from different

antennas or if one signal is coming from a cable system, etc. If

using a common antenna, use a good quality two way splitter to

split the antenna and feed each input.

2) Plug the power cord from the unit into the power source.

3) Follow the instructions in the programming section above to

set the channel map and channel number for both INPUT

MODULE A and INPUT MODULE B.

4) Set the QAM SYMRATE to PRESET.

5) Set the MULTIPLEX setting ENABLED

6) Set the INPUT B OFFSET to 10. Read details in program-

ming section to determine if you need another value.

7) Select the desired MPEG programs. (See the previous

section for details.)

8) In the PSIP menu, select BASIC MGT VCT for now, this may

be changed later. See programming section for detail.

9) In the VCT TABLE menu, select TVCT.

10) In the MAJOR CHANNEL menu, select OUTPUT CHAN-

NEL. This may be changed later.

11) From the QAM MODE menu, set the QAM modulator to

QAM-256B for use in a DigiCipher II environment. If DVB, use

QAM-256A instead.

VIDEO: This menu entry allows the user to select between S-

VIDEO and COMPOSITE video input for each selected encoder.

FORMAT: Either MPEG2 or MPEG4 H.264 may be selected as the

output format for the selected encoder using this menu item.

Encoder 2 on a given SDE24 has no option. It is forced to MPEG2.

RESOLUTION: The resolution of the video output of each encoder

may be selected from this menu item. The choices range from 720

x 480 thru 353 x 240 as shown on the software flow chart on page

BRIGHTNESS, CONTRAST, SATURATION and HUE: These

menu items allow the user to assign each of these parameters of

the output video values from 0 to 255.

MAX AUDIO IN:

This menu entry allows the user to set the

maximum audio input which may be input to the selected encoder.

The choices are 1 Vrms or 2 V rms.

AUDIO GAIN: The audio output level can be chosen from this

menu item by selection of the appropriate gain. The values range

from + 15 dB to - 15 dB. Audio output can also be completely

eliminated using the 'MUTE' selection.

AUDIO ENCODER: The SDE24 includes audio encoders for Dolby

Digital Stereo commercial encoding (AC3) or MPEG1 Layer 2 audio

encoding (MP2). In the USA, the majority of applications will use

AC3 but if your network is using Annex A (DVB) set top boxes, they

may require the MPEG audio selection. Some TVs and set top

boxes will decode either mode but be sure to set the encoder to the

mode used by other programming on your system to insure

complete compatibility. The AUDIO ENCODE(R) menu allows you

to select either AC3 or MP2. Use the up/dn arrow keys to toggle

between the two settings.

12) In the QAM SYMRATE menu, select PRESET.

13) Set the INTERLEAVER to I128,J1 if in a DigiCipher II

environment. There is no interleaver menu when the QAM

mode is set to A (DVB).

14) Set the OUTPUT FORMAT to NORMAL.

15) Set the OUTPUT CHANMAP and OUTPUT CHANNEL to

the desired EIA CATV output channel.

If the second program is being input to a ASII Module via the ASI

input instead of a DTD1000, the same steps apply except that

there will be no parameters to set for the ASII MODULE.

SET TOP BOX MAPPING

When setting up a program map for your set top boxes to include

off-air channels that are multiplexed by the MEQ1000 be sure to

inform the programmer that the MPEG program numbers for the

programs coming in through INPUT MODULE B or ASI B have

been offset by the amount selected in the INPUT B OFFSET

menu. As an example: If input A is providing a channel with

MPEG programs 1 and 2 in the stream and input B is providing a

channel with MPEG programs 1, 2, 3, 4, and 5 in the stream, and

the INPUT B OFFSET is set to 10, then the new output signal will

contain MPEG programs with program numbers of 1, 2, 11, 12,

13, 14, and 15. If the set top is not looking for the right program

number, you will not receive any video!