GUIDE TO INSTALLATION AND OPERATION
18
| HCO-1822
3.4.6 The Reference panel
The HCO-1822 output signals should always be genlocked
to some reference source. The genlock source is selected in
the Reference control panel. Use the radio buttons in the
Reference Source area to select from the following options:
•
Auto – this mode selects the first source detected in this
order of priority:
o
Reference input
o
URS
o
Selected Input signal
•
Reference input – selects the signal connected to the
rear-panel REF IN connector
•
URS (Universal Reference Signal) – selects the internal
reference from the backplane
•
Input – uses the currently-selected input signal.
URS Format – use the radio buttons in the URS Format area
to select whether the URS is OFF, 29.97 Hz or 25 Hz.
The genlock is used to assure a switch during the vertical
interval of the genlock source.
See the Timing panel (section 3.4.4) for a display of the
measured timing between the outputs and the reference, and
to set the output timing.
3.4.7 The Audio Embed panel
SD Audio Embed Input 1 & SD Audio Embed Input 2
Use the pulldown to select the number of audio bits to be
embedded at the output from these inputs.
Audio is processed in the HCO-1822 according to the
following rules:
1. Supported serial formats include
o
SMPTE-299,
o
SMPTE-272M-C (Embedded audio)
2. When switching PCM audio, a fade-out / fade-in is
performed on a few samples to avoid audio glitches.
3. When switching Dolby-E and AC-3 audio, no fade-out /
fade-in is performed. For Dolby-E, the channel switches
on the video switching line (i.e. between 2 packets).
4. Audio embedding is 20 or 24 bits (only for SD inputs).
5. 16 channels per input are supported
Note: These controls are disabled when clean switch is
disabled and the Grass Valley ALC option is not enabled. In
this case, the HCO-1822 acts as an intelligent 2x1 router.
Figure 3.22 Reference Panel configuration
Figure 3.23 Audio Embed panel
