When you are staying at a hotel, each room is generally equipped with a television set. It is a compulsory service, some hotels only show local TV broadcasts and there are also hotels that are better at serving foreign FTA ( free TV) and also some paid television broadcasts. This broadcast is taken from the satellite dish and distributed via MATV / CATV devices or known as analog cable tv. Years ago i was staying at a hotel which room has a TV set paired with STB - IPTV broadcast from Telkom's UseeTV . Then i wondered how it would be if the hotel rooms let say 50 rooms, then how much is the monthly subscription fee? How to manage the internet bandwith if one HD channel required around 5 Mbps of bandwith ?
Several years ago i had a project to install signage software at a hotel. This software will be used as a tv content for one of the information channels at the hotel's CATV system. The device in the picture above is called CATV Head End which consists of a broadcast source from a parabolic dish and receiver or via DVD player, then the audio video signal goes to the RF Modulator - Combiner - and ends with a Power Amplifier at each point which is considered experiencing a weakened reception. The quality of the TV broadcast in the room is beyond expectation, if the room is far from the CATV "booster" then there must be some complains that tv picture had many noises which deteriorates the broadcast quality so bad.
By using RF modulator for analog CATV distribution , the maximum number of broadcasts cannot be more than the number of Analog TV Channels in the VHF - UHF spectrum which are generally 60. To make it more inefficient is the fact that more channels you wanted then you must use the same amount of satellite receivers / decoders + RF Modulators. It will be less economical, for example for a hotel or boarding house with 20 rooms, can you imagine how much money is needed for 60 receivers and modulators per channels ? If you reduce the channel numbers than the quality of service to the hotel is considered incomplete. Why don't we bring the decoders to the rooms instead ?
This device is called as "MULTI SWITCH" which functions is to divide the signal from the LNB (satellite dish) to several receivers / decoders. Usually in the electronics market there are 2 types of Multi Switch, first is a "passive type" where the supply voltage comes from the receiver and is suitable for distribution at household where the distance between rooms are near. The other type is "Active" which has a separate power supply and is suitable for use with multiple receivers and the distribution distance is quite long. Another special type of Multi Switch is "Cascade-able" which means that the LNB signal from this MultiSwitch can be "Repeated" to another Multi Switch (in series). So that those cascade-able can reduce the use of additional satellite dishes and of course it is easier to arrange the wiring because it can be broken down, such as installing 1 multi switch on each floor of the building. This is easier to set up than centrally in one room which can be a pain in the coaxial cable arrangement.
Now let's take a look at steps on how to make satellite tv distribution which was done previous years ago
HARDWARE :
1. Parabolic Dish - C band - 7 feet.
This 7 feet parabolic dish were chosen for economic reasons and the two satellites were good enough for 7 feet with dual twin LNB.
2. Dual Out LNB - Split Polarity
The multi switch will functions as a polarity selector / switch of each broadcast then distributed for many receivers. So we need a special LNB which polarity Vertical and Horizontal are on different ports. Nowadays as the multiswitch capability is getting better, a simple 2 out LNB is sufficient for this purpose.
3. Bracket / Scalar Ring for twin LNB.
If you are only using single satellite then a single scalar ring is enough.
4. Multiswitch 5 x 8/16/24/32
Unfortunately the 5 x 24 type was out of stock so we use the 5 x 32 type. Why 5 inputs? because 4 inputs for LNB to Palapa & Telkom satellite and 1 input for UHF antenna. So if you are worried that your digital satellite channels will be scrambled (especially in sport match), then you can combine the UHF lines using a multiswitch + diplexer.
5. Coaxial Cables, F Connectors, I connectors, Panel Boxes and other equipment
ASSEMBLY and SATELLITE TRACKING
1. Assembly the 7 feet parabolic dish in a upward free location for allowing an easy satellite tracking.
2. Install the two LNBs with the Telkom 4 on Focus Position while Palapa (backup) is on the WEST side with a distance of about 2 fingers. The depth of LNB is around 40 for Palapa and 38 for Telkom (varies depending on the parabola / LNB brand). Adjust the tilt / elevation and azimuth direction with the satellite distance to the installation location. Plug in 4 coax cables into 2 LNBs and try to test the connection per port as well as the satellite tracking via tv monitor.
3. Plug in 4 LNB cables into the Multiswitch ports
The ports configuration above is 22khz off for the Palapa satellite and 22khz on for the Telkom satellite.
4. Connect the coaxial cable to every room and setup the receiver
If you have difficulty in setting up receivers one by one then the easy way is by copying the "user db / user database" to USB, so first complete settings in 1 receiver and then copied to another receiver via usb flash drive. This copy method only works with specific STB and preferably all receiver in every rooms are uniform / similar. The number of broadcasts for the combination of Palapa D & Telkom 4 satellite is around 120 channels (Free To Air) and 50 premium pay tv channels.
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