BroadBand reference Guide - Blonder Tongue Laboratories Inc.

AQT - ATSC to QAM Transcoder
• OUTPUT CATV — permits the entry of the desired output
channel number to program the AQT module, tuning range is
NTSC CATV channel 2—135, (digital center frequency)
• INPUT FREQ — permits the entry of the desired input signal
center frequency to program the AQT module, tuning in frequency
range of 54—864 MHz, (digital center frequency)
• OUTPUT LEVEL — permits the entry of the desired output signal
level in dBmV as an average power measured signal, range is +30
to +40 dBmV, optimum SNR performance is achieved by setting
the unit output @ +40 dBmV
• OUT QAM MODE — permits the entry of the desired QAM
mode, the unit has six available QAM modes:
o NORMAL: The "NORMAL" QAM mode outputs a 6 MHz QAM
modulated signal and must be used with 8VSB input
o OFF: The "OFF" QAM mode outputs no signal from the module
(When a module is placed in the QAM off mode, the status LED
indicator will blink)
o CW: The "CW" (carrier wave) mode outputs a CW signal that
is very useful for measuring the output level of the unit, the
CW signal is a true representation of the QAM signal level
(When a module is placed in the QAM CW mode, the status
LED indicator will blink) (See the QAM Signal Level Testing
section for more detail)
o CW ALL: Puts all modules installed in a rack chassis into CW
mode for ease of level adjustment
o NORMAL ALL: Returns all modules installed in a rack chassis
to normal mode required for normal operation
o PASS THRU: Disables null packet processing - This mode
must be used when the input to the AQT is QAM
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