Drake MQM6000L Multiplexing QAM Modulator - Manual (Page 9)

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UNIT ID: Select the desired unit identification number when connecting the 'RS232 iN' connector to a PC or modem
for remote control using 'Drake Remote Control Software'. Numbers 1 thru 63 may be used. if zero (0) is selected,
the PC will ignore the unit.
RS232 BAUD RATE: this setting determines the baud rate at which the mqm6000L communicates with the remote
PC. Settings available are 2400, 4800, 9600 and 19,200. All units 'daisy chained' to the remote PC or modem must
be set to the same baud rate.
MPEG PROGRAMS: this menu provides selections to determine which programs are multiplexed to form the new
multiprogram transport stream output that will be supplied to the qAm modulator section.
Choose the DefAULt setting to multiplex the lowest numbered (or only) mPeG program from each of the six ASi
inputs.
Choose the SeLeCt PRoGRAmS setting to allow the operator to pick which program (or no program) from each
of the six ASi inputs is to be included in the output multiplex. only one program from each of the six inputs can be
selected. this selection must be made using a PC connected to the RS232 iN port and running the 'Drake Digital
Headend Remote Control Software' program.
it is the operator's responsibility to be sure that the total data rate of these programs does not exceed the maximum
data rate for the output qAm mode that will be used. if the total input rate is too large, some programs will have to
be dropped from the multiplex.
QAM MODE: this menu allows the user to set the modulation type for the output. Choices range from qAm-
16A through qAm-1024b. 'A' suffixes indicate Dvb compliant feC and the b suffixes indicate DigiCipher ii feC
encoding. Note that the output qAm mode usually must be qAm-256. for CAtv systems using DigiCipher ii, select
the qAm-256b mode. for DiSH Network qAm distribution or other Dvb systems using Dvb set tops, choose the
qAm-256A mode.
GRAY ENCODING: this menu is only available when qAm modes qAm-16A through qAm-1024A, are selected.
the choices are Dvb and DAviC. Dvb is normally used for video.
QAM SYMRATE: this menu allows selection of the output qAm baudrate or symbol rate. Set as required by the
set top box.
if PReSet is selected, the symbol rate will be set according to the qAm mode that has been selected. if mANUAL
is selected, pressing the right or left arrow buttons will allow selection of symrates from 1.000 thru 7.000 mSym/Sec.
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. 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 normally set 5 db to 10 db below analog NtSC channels when balancing a system. PRbS menu entries are
used for testing purposes only and should normally not be selected by the user.
OUTPUT CHANMAP, OUTPUT CHANNEL: Select the desired eiA CAtv channel output using these two menus.
RF LEVEL: Select the desired Rf output signal level. the available range is between +30 dbmv and +42 dbmv,
selectable in 0.5 db steps. the output accuracy is ± 1 db.
Setup and Programming (continued)