HCO-3931
12G/3G/HD Change-over with Clean Switch & ALC
The HCO-3931 is a 4x1 12G/3G/HD SDI change-over that supports 16 channels of embedded audio and metadata. The module can perform a video and audio “clean and quiet switch” between sources. In the event of a power failure, the PGM signal is protected by a bypass circuit fitted on the rear module, maintaining the integrity of the selected MAIN or BACKUP signals at the output, and it is fully controllable via GPI. Two rear modules are available with different bypass circuits, the HCO-3931-3DRP-H offers an active bypass that retains PGM signals for at least 48 hours while the HCO-3931-3TRP-HR uses 12G SDI rated bypass relays for extended protection.

FEATURES
- 12G/3G/HD SDI input/output
- Main, Backup and two Emergency inputs
- On-Air Program and Preview outputs with two connectors each (signal copy)
- Choice of external or frame URS reference input
- Audio/video de-glitcher to handle video hot switch on every input
- Clean and quiet switch function of video and 16 channels of audio on Program output
- Optional 16-channel Automatic Loudness Control
- GPI – based inputs selection and tallies
- Electronic switching with two rear panels that maintain selected input upon power loss for Primary Main and Backup inputs:
- HCO-3931-3TRP-HR triple rear with relay backups
- HCO-3931-3DRP-H double rear with active bypass for a minimum of 48 hours of protection from a power loss
- Automatic change-over mode using internal signal analysis with configurable probes for all inputs
- Manual change-over by local frame controller, GV Orbit or GPI
- Configuration, control, monitoring and alarm reporting via GV Orbit Network Orchestration solution
SPECIFICATIONS
SDI (Inputs/Outputs)
Physical: 8 HD-BNC connectors: 4 in, 4 out
Supported Formats:
- HD: SMPTE ST 274: 1080i59.94, 1080i50
- HD: SMPTE ST 296: 720p59.94, 720p50
- 3G: SMPTE ST 425 level A (mapping 1), level B dual link: 1080p59.94, 1080p50
- 12G: SMPTE ST 2082-10: 2160p59.94, 2160p50
Cable length (Belden 1694A):
- HD: 180m (590 ft.) at 1.485 Gb/s
- 3G: 100m (328 ft) at 2.970 Gb/s
Cable length (Belden 4794R):
- 12G: 30m (98 ft.) at 11.88 Gb/s
Reference Input
Physical: 1 HD-BNC connector
Standard: SMPTE ST 170/SMPTE ST 318/ITU 624-4 blackburst
Return loss: >35 dB up to 5.75 MHz
GPI (10)
Connector: HD-15, opto-isolated, common ground
GPI IN (5): Contact closure to ground
GPI OUT (5): Contact closure to ground
External pull up voltage: 3.3V to 24V max.
External GPI power: 5V nominal
Video Processing Performance
Signal path: 10 bits
Latency:
- 0.5 lines without Clean Switch and ALC enabled
- Maximum of 2.5 lines with Clean Switch or ALC enabled
Audio Processing Performance
Quantization: 20-24 bits
Sampling: 48 kHz, synchronous
Number of channels: 16, 4 groups
Audio latency:
- 1.8 ms without Clean Switch and ALC enabled
- Add 42 µs if Clean Switch is enabled
- Add 21 µs if ALC is enabled
Electrical
Power: 15W maximum
NOTE: Cable length specifications are for worst case scenario when outputs are protected by the active bypass or relay, refer to the manual for more details.
MEDIA GALLERY




ORDERING INFORMATION
HCO-3931
12G/3G/HD Change-over with Clean Switch
HCO-3931-3DRP-H
Double rear panel active bypass HD-BNC. Active bypass offers a minimum of 48 hours of protection from a power loss
HCO-3931-3TRP-HR
Triple rear panel bypass relays HD-BNC. Bypass relay offers persistent passive protection from a power loss
Software Options
HCO-3931-OPT-ALC
16-channel on-board Audio Loudness Control option
Hardware Options
NSH15M
HD-15 to terminal block adapter
Remote Control
GV Orbit version 1.2 or higher, iControl or iControl Solo (version 7.50 or higher required)