DRAKE MQM1000 Buku Petunjuk - Halaman 10

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Setup and Programming, continued

find out which MPEG programs are defined. If you wish to

view the MPEG program numbers of programs that were

found, follow the procedure below:

VIEWING MPEG PROGRAM NUMBERS

In order to see the MPEG program numbers of incoming

streams, the following procedure can be followed:

1) Press the ENTER button for 2 seconds to enter program

mode. Release button. Display will be flashing.

2) Press the ENTER key again and hold. By continuing to

hold in the ENTER button, the following display will be

slowed down so that program numbers can be read as

they scroll by.

3) A screen will be displayed that indicates:

PMT PROG A xxxx or PMT PROG B xxxx.

4) The xxxx field will be a number that corresponds to the

MPEG program number of a program found in the PMT

table for the indicated (A or B) input. As the button is held,

all entries for input A will scroll past and then entries for

input B will scroll past.

5) Release button and if necessary repeat steps 1 - 4.

B) If SELECT PROGRAMS was chosen, the unit will read

the PAT tables from both inputs and then display:

MPEG PROG XXXXX: (XXXXX is a number from 00001 to

65535) on the top line of the display. Using the right and

left arrow keys, you can scroll through all 65535 possible

program numbers.

Don't be alarmed by the large number of possibilities

because if the arrow key is held down, the scrolling will

speed up so all 65535 possible numbers can be scanned

in a short time - any time an entry is found at a given

program number, the scrolling will slow down to give the

operator time to see it and stop scrolling, if desired.

Usually, all programs are known to be numbered between

01 and 20.

For each MPEG program number, displayed on the top

line, the bottom line, on the right, will indicate A, B, AB, or

nothing. This will indicate that the program number on the

top line was found in input A or B or AB for both or not in

either one if blank.

To select programs to be included in the output multiplex,

use the up and down arrow keys to select NOT SE-

LECTED, INPUT A, INPUT B, or INPUT A+B. If NOT

SELECTED is used, then this program number will not be

present in the output and any programs with this program

number that are present in the A or B inputs will be filtered

out. If INPUT A is selected, the A input program only is

used. If INPUT B is selected, the B program is used and A

filtered out. If INPUT A+B is chosen, then both are ac-

cepted if present.

Note: It is OK to use this menu to set up desired program

selections 'off line'. That is, with no actual input at the

present time. Programs may be selected that may not

currently be in the input stream but are desired at some

future time.

Note: It is possible to select both programs with the same

program number - one from A and one from B as long as

the INPUT B offset is set so that the B program number

plus the offset amount does not duplicate a program

number from the A input. The offset is not included in the

MPEG program number display being discussed above

but the offset will be added to all MPEG program numbers

from the B input when they are added to the output

multiplex.

DEMOD B CHANMAP, DEMOD B CHANNEL, DEMOD B

MODE, DEMOD B SYMRATE:

See descriptions for DEMOD A above. These are equiva-

lent settings for the DEMOD B demodulator input, when

installed.

INPUT B OFFSET: When the DEMOD B or ASI input has

been installed and selected in the MULTIPLEX menu, this

menu will be present. Because the two incoming transport

streams are likely to have overlapping use of MPEG

program numbers, the DQT861 or MQM861 will pass the

program numbers from input A unchanged and an offset,

equal to the value chosen in this menu, will be added to

the program number of programs from the second input.

This same offset value will also be added to the minor

channel number in the VCT table for programs from the

second input source. Usually an offset of 10 will be

adequate but if you know there are programs in the signal

input to input A using program numbers above 10, a higher

offset may be required. Values between and 10 and 90, in

increments of 10, are available for selection. When it is

known that there is no overlap between input A and input B

stream program numbers, a 0 offset setting can be used.

Be cautious if this is the selection that is chosen.

PSIP: This menu provides a choice of how the unit

organizes the PSIP information from two ATSC streams

that are being multiplexed.

In the ENABLED setting, information from the MGT and

VCT tables from both signals will be used to build a new

table for the combined output signal. Both input streams

must have these tables present in order for the unit to be

able to perform this operation. EIT tables will be pro-

cessed so as to provide program information, if present,

for the next 12 hours. This selection is the only one that

passes EIT table program information to the multiplexed

output signal. RRT and STT tables from Demod A are

passed through.

If the broadcast station is not transmitting complete MGT

and VCT tables, the ENABLED selection cannot be used.

In this situation, DISABLED may be selected. In DISABLED

mode, the unit does not process or output any MGT, VCT,

or EIT tables. This can be a fine solution for cable systems

that use set top boxes which operate from their own

system channel map and have no need for these tables.

MPEG program information is still processed. Some retail

consumer QAM set tops operate perfectly in this mode and

others may not.