Hirschmann PAL 1 HU, Manual

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Sound2 modulator T2M 501/1
In the sound2 modulator the second sound carrier (33,158 MHz) is frequency-
modulated by the matrixed audio signal 2 and the pilot signal. The sound2 mo-
dulator generates the identification frequency the pilot is modulated with.
Carrier frequency The carrier frequency is derived from the vision carrier, for which purpose the
vision/sound modulator makes available the reference signal "REF-SND2".
Sound carrier lowering The modulated IF carrier 2 can be lowered by 3 dB with a switch on the assem-
bly and then is passed to the vision/sound modulator.
Transmission mode The transmission mode (mono/stereo/2sound) is determined from the data line
of the video signal (on VIDEO MAIN SYNC IN) with a data line decoder.
The LED "DATA LINE" lights up, if the data line is present.
The transmission mode can also be determined with the monitoring software or
on the connector "SOUND MAIN IN". If it is, the LED "REMOTE" lights up.
The transmission mode is shown by LEDs on the front panel.
The following list indicates the priority ranking of the controls:
l
1. Control with the monitoring software.
l 2. Hardware control via the rear panel assembly (MODE).
l 3. Data line analysis.
l
4. If no data line is detected, modulator switches automatically to 2sound
operation.
Pilot The pilot and the identification frequency are locked to the line frequency (on
VIDEO MAIN SYNC IN). The pilot is modulated at a different frequency
depending on the transmission mode.
l
MONO unmodulated (0 Hz)
l
STEREO 117,5 Hz
l 2SOUND 274,1 Hz
The pilot can be switched off (on the assembly) to carry out measurements.
Controls The following controls can be carried out by the monitoring software:
l
Sound 2 (S2OFF): Switches the output off
l
Sound State: Determines the transmission mode mono/stereo/2sound
Operation
Manual
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