10 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.
