Cisco Model 6109 6 MHz Off-Air Reference (NTSC) Fiche De Données

 

 

 

 

 

The Model 6109 6 MHz Off-Air Reference provides a convenient method to phase lock Scientific-Atlanta video 
modulators and upconverters to an off-air VHF broadcast source. It offers an attractive and cost-efficient method 
for reducing co-channel interference in CATV systems. This interference is often caused by ingress of high power 
VHF signals into the distribution plant or subscriber premises equipment.  
 

The Model 6109 Off-Air Reference provides a nominal 6 MHz reference signal output from the VHF broadcast 
video carrier and a sample of the modulator/upconverter program IF. This 6 MHz signal is then used as a 
reference input to a video modulator to maintain its RF output in phase with the off-air VHF video carrier. Phase 
locking a CATV modulator to an off-air source can reduce and stabilize visible beats in the video signal of a 
program source that is subject to ingress interference. 
 

 
Features 

Built-in VHF tuner 

Supports all VHF channels  

Automatic bypass mode 

Modulator remains functional if broadcast input signal is lost 

Precision 6 MHz output 

Modulator maintains low noise specifications  

Flexible operation 

Manual or Remote control modes 

Composite IF input 

Supports IF transport in source /hub networks 

1 RU package 

Minimizes rack space