Изделия для кабельного телевидения

 

Изделия для кабельного телевидения

 

 

Network Unterface Unit

The NIU is designed especially for high quality two way cable TV networks.

The NIU can be used as a separation between the network of the cable operator and the in-house network.

There are 4 (2-way) TV outlets; 2 with 4 dB gain to access further located TV sets.

Data and telephone outlet have a separate returnband compared to the TV returnband. In this way interference of ingress from one to another is avoided.
In case of power failure input and telephone output are directly connected with the aid of a relays. This ensures life line functionality of telephone services.

A power feedtru from RF input to telephone output makes it possible to power the telephone equipment from the cable network. The NIL) itself has a separate input for powering (DC). It can also be powered via a 0 dB TV outlet with the aid of a power inserter. In this way the NIL) can be powered remotely. All outputs have a minimum of 20 dB isolation between each other. A 30 dB testpoint at the input makes it possible to check input signal to distinguish signal failure against NIU failure without disconnecting equipment.

All signal input and outputs can withstand 1500V impulse voltage.

 

	NIU 25/47	NIU 65/88
Bandwidth downstream  TV Data/telefony	47-860 MHz 108-860 MHz	88-860 MHz 108-860 MHz
Bandwidth upstream TV Data/telefony	5-12 MHz 15-25 MHz	52-65 MHz 5-48 MHz
Gain downstream TV OdB TV 4dB Data Telefony	O dB 4 dB O dB O dB	OdB 4dB OdB OdB
Attenuation upstream TV 4d TV OdB Data/Telefony	8 dB 12 dB 6 dB	8 dB 12 dB 6 dB
Intermodulation Cenelec 42 Channels Vin: 16 dBmV flat CTB CSO	> 60 dB > 60 dB	> 60 dB > 60 dB
Flatness All frequency bands	<± 1,5 dB	<± 1,5 dB
Reflexion attenuation	> 16 dB	> 16 dB
Noise < 7,5 dB	< 7,5 dB
RFI-lsolation Cenelec EN50083-2	> 85 dB	> 85 dB
Propagation time downstream	< 20 nsec	< 20 nsec
Insulation between ports	> 20 dB	> 20 dB
Connectors	F-connector	F-connector
Body material	Zamac	Zamac
Dimensions	L240, H100, D40 (Plastic cover)	L240, H100, D40 (Plastic cover)