What Is Multiswitch & Repeaters In Cable Tv Equipment ?

catv multiswitch

What Is Multiswitch

multiswitch for catv

Multiswitch is a cable tv equipment.It is mostly used in rural side areas where cable tv connectivity is not available.It can also use in buildings and hotels where number of connections are high in small place. Input of multiswitch connected to the LNB and output to the satellite receiver. Two or many different satellite dish can be connected to this switch.So that we can provide multiple connections to users using limited number of dishes.

Working Of Multiswitch

There are different kind of multiswitch like 2*4 , 2*8 , 3*4 ,  3*8 , 4*4 , 4*8 and 5*8 etc. The first digit shows here number of input to multiswitch whereas second number denotes the number of outputs of multiswitch. So if there is 5*8 multiswitch then it means it have 5 input and 8 output. 4 inputs can be 4 different satellites (single polarity) or 2 different satellite with horizontal and vertical both polarity. Now only 1 input is left out of 5 inputs.

This 5th input can be cable tv input or terrestrial antenna. To better understand the working of multiswitch a figure have shown below.

multiswitch implementation

As shown above in the figure we are using two multiswitches in cascade connection. Here we are using 5*8 multiswitch which denotes 5 inputs and 8 outputs.If there is requirement of more connection then we can connect more multiswitch in cascade mode.Now as we can see in figure the upper multiswitch is having 5 inputs from different dishes and one from cable tv connection.

We are using here four dishes these are ku band dishes which we generally mount on terrace. There are two individual dishes for DD Direct where one is for Horizontal polarization and other is for vertical polarization.Same thing is with the TATA SKY dishes. One is for horizontal polarization and another is for vertical polarization.

The 5th input port is connected with cable tv. This is single port for cable tv because there is no need for any kind of polarization. Because this feed is coming from headend and at subscriber end we are using STB (Set Up Box) which is Network Binded.Thus in multiswitch there are individual port for each kind of signal.

The outputs of these switches are going into the satellite receivers.The output of these satellite receivers is going into the television that is composite signal.

What Are RF Splitters RF Dividers RF Combiners

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Subscriber End Configuration

At the subscriber end the subscriber need to tune his satellite receiver. He needs to enter the frequency , symbol rate,satellite degree and select the polarization.He needs to do these configuration in his satellite receiver.The he would be able to see programs.

SO when he tunes the satellite receiver the receiver sends the DC (Direct Current) signal in volts to the LNB via multiswitch.If this voltage level is +14 Volts then satellite receiver will tuned for Vertical polarized Transponder.If this voltage is +18 volt then satellite receiver will tune for the Horizontal Polarized transponder.

A 22 KHz tone is also sent by satellite receiver to dish antenna.This is used to switch transponder. 22 KHz tone tune the LNB for high frequency transponder. Thus this tone is used to switch the transponder.

Repeaters For CATV

Repeater is also known as Cable Tv Equipment.If there is requirement of high number of connections then we can use repeaters.Reapeaters are as like amplifiers.

If there is large distance between one multiswitch and another multiswitch then we need to use repeaters.Repeater are used in between two multiswitches. Repeaters have equal input and equal output like if there is 5 inputs then there will be 5 outputs for this repeater.Thus repeaters can only be used in between two multiswitches to amplify the signal.

Conclusion

Multiswitches are useful to reduce the coverage size of terrace by dishes.Multiswitches are expensive option rather than simple cable tv connection.It is only useful when cable tv connection is not available.

We have option to input cable tv feed in multiswitches. Multiswitchs receive the IF signal from the satellite dishes which ranges from 950 MHz to 2150 MHz. While same multiswitch also accept the cable tv feed which ranges from 48 MHz to 860 MHz. So there is no any chance of interference of between LNB feeds and Cable Tv feed because frequency ranges are different.So we can use both signals in same Multiswitch.

 Know More About  What is IPTV And IPTV Technology

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