Club CDFreaks - Knowledge is Power - View Single Post - Building a custom satellite system & choosing a non-proprietary satellite receiver

**Seán** · 08-05-2004

Note: The channel selections mentioned below are based on choosing a satellite receiver in Europe since this is what I am familiar with. Similar rules will apply to choosing receivers in other continents also

Satellite Receiver

As with Sky digital, a digital satellite receiver is required to decode the satellite transmissions into a format that can be displayed on screen. The receiver works by sending out power on the coaxial cable to power the LNB and the Diseq switch if present. It also sends out different voltage levels, tones and Diseq commands to tell the LNB which band to pick-up as well as what satellite to choose on a motorised or multi- dish set-up.

There are several types of digital receivers to choose from. Analogue satellite receivers are gradually becoming obsolete. An analogue receiver can only pick up analogue transmissions where as a digital receiver can only pick up digital transmissions.

FTA Receivers

The most basic digital receiver is known as a FTA system which means that it can only pick up free-to-air transmissions. FTA systems are relatively cheap and are mainly intended for those who just want to improve their channel selection or pick up the BBC digital channels selection where terrestrial BBC reception whether analogue or digital is weak or not available. These are also known as BBC systems or God channels receivers since both sets of channels are not encrypted.

Receivers capable of decoding encrypted transmissions

For the reception of encrypted channels, a digital receiver with either a built-in CAM or removable CI slots is required along with a suitable viewing card. For the best customisability, it is best to choose a receiver with at least one or more CI slots to allow for future expansion.

The CAM – Conditional Access Module

A CAM is a module that decrypts one or more encryption systems. In the early days of analogue transmission, a decoder (descrabler) use to be a physical set-top box which connected to the receiver. Now the decoders are in the form and size of PC Cards known as CAMs which plug directly into a receiver with CI slots. Like with a physical set-top decoder, most CAMs require a suitable viewing card in order for the CAM to derypt channel the user is entitled to watch.

The most popular encryption systems in use are Viacess, Irdeto, Nagravision, Betacrypt, Seca, Videoguard and Conax. Seca is also known as Mediaguard and Videoguard is also known as NDS. Many receivers come with a built-in cam, which can either receive one of these or all of these. For receivers with one or more CI slots, a PC-Card type CAM (PCMCIA) can be installed for decoding additional encryption systems.

The most popular multi-encryption support CAM’s at present are the Magic Module and the Matrix Reloaded CAM. Both of these are capable of decrypting most of the above encryption systems with an appropriate viewing card (and subscription). Note that these programmable CAM’s are often supplied blank for legal reasons and must be programmed with the appropriate downloadable firmware prior to use. Dedicated encryption CAM’s such as a Viaccess CAM are supplied ready for use.

Note that while Sky uses the Videoguard (NDS) encryption system, there are no PC Card CAMS available which can handle Videoguard. Decryption support is only available as an intregated CAM with a proprietary Videoguard system such as the receivers offered by Sky Digital.

Other Features

Besides TV, radio and encryption support many receivers off various other features that the consumer may be interested in looking out for. These include digital audio out or pass-thru, Teletext decoding, EPG, Diseq, PVR and 36 volt output.

Teletext – Nearly all digital receivers on the market offer Teletext decoding support. Unlike terrestrial analogue TV, the satellite video, audio and Teletext streams are separate from each other. When a receiver with Teletext support detects the Teletext stream (PID), it will add it to the field lines of the picture to enable Teletext viewing from a Teletext compatible TV.

EPG – Electronic Programming Guide is a useful feature to determine what is on next or at a later stage. Most satellite channels provide what is currently on and the next programme. Some channels even provide the schedule up to a week or two ahead. Some satellite receivers allow the user to choose programmes to record. Once a chosen programme time has reached the receiver changes over to the appropriate channel for the duration of the programme.

Diseq – Diseq is a signalling system which the receiver sends out to control Diseq switches and Diseq based motorised dishes. Diseq v.1.0 can operate either a 2-way or 4-way Diseq switch. Diseq v.1.2 operates a low power Diseq 1.2 motor with dish sizes up to around 1 metre.

PVR – PVR support allows the satellite receiver to function in the same way as a TV based PVR. With PVR support, the user can pause live broadcasts as well as select EPG programmes or a scheduled times to watch later. Note that PVR systems usually have two cables from the dish. One is for live viewing and the other is for the PVR, which allows the user to watch one channel while recording another. PVR systems with only one input will not allow the user to change channel while it is recording a programme.

36 Volt Output – Receivers with a 36 volt out allow the motorised control of a large motorised dish setup with a separate power cable to the motor. The advantage of having the power supply built in is that the user does not need to operate a separate power supply to move the dish.

08-05-2004	#2 (permalink)
Seán News Coordinator, Reviewer & Senior Moderator Join Date: Jun 2002 Location: Republic of Ireland (North West) Posts: 2,578	Choosing a non-proprietary satellite receiver Note: The channel selections mentioned below are based on choosing a satellite receiver in Europe since this is what I am familiar with. Similar rules will apply to choosing receivers in other continents also Satellite Receiver As with Sky digital, a digital satellite receiver is required to decode the satellite transmissions into a format that can be displayed on screen. The receiver works by sending out power on the coaxial cable to power the LNB and the Diseq switch if present. It also sends out different voltage levels, tones and Diseq commands to tell the LNB which band to pick-up as well as what satellite to choose on a motorised or multi- dish set-up. There are several types of digital receivers to choose from. Analogue satellite receivers are gradually becoming obsolete. An analogue receiver can only pick up analogue transmissions where as a digital receiver can only pick up digital transmissions. FTA Receivers The most basic digital receiver is known as a FTA system which means that it can only pick up free-to-air transmissions. FTA systems are relatively cheap and are mainly intended for those who just want to improve their channel selection or pick up the BBC digital channels selection where terrestrial BBC reception whether analogue or digital is weak or not available. These are also known as BBC systems or God channels receivers since both sets of channels are not encrypted. Receivers capable of decoding encrypted transmissions For the reception of encrypted channels, a digital receiver with either a built-in CAM or removable CI slots is required along with a suitable viewing card. For the best customisability, it is best to choose a receiver with at least one or more CI slots to allow for future expansion. The CAM – Conditional Access Module A CAM is a module that decrypts one or more encryption systems. In the early days of analogue transmission, a decoder (descrabler) use to be a physical set-top box which connected to the receiver. Now the decoders are in the form and size of PC Cards known as CAMs which plug directly into a receiver with CI slots. Like with a physical set-top decoder, most CAMs require a suitable viewing card in order for the CAM to derypt channel the user is entitled to watch. The most popular encryption systems in use are Viacess, Irdeto, Nagravision, Betacrypt, Seca, Videoguard and Conax. Seca is also known as Mediaguard and Videoguard is also known as NDS. Many receivers come with a built-in cam, which can either receive one of these or all of these. For receivers with one or more CI slots, a PC-Card type CAM (PCMCIA) can be installed for decoding additional encryption systems. The most popular multi-encryption support CAM’s at present are the Magic Module and the Matrix Reloaded CAM. Both of these are capable of decrypting most of the above encryption systems with an appropriate viewing card (and subscription). Note that these programmable CAM’s are often supplied blank for legal reasons and must be programmed with the appropriate downloadable firmware prior to use. Dedicated encryption CAM’s such as a Viaccess CAM are supplied ready for use. Note that while Sky uses the Videoguard (NDS) encryption system, there are no PC Card CAMS available which can handle Videoguard. Decryption support is only available as an intregated CAM with a proprietary Videoguard system such as the receivers offered by Sky Digital. Other Features Besides TV, radio and encryption support many receivers off various other features that the consumer may be interested in looking out for. These include digital audio out or pass-thru, Teletext decoding, EPG, Diseq, PVR and 36 volt output. Teletext – Nearly all digital receivers on the market offer Teletext decoding support. Unlike terrestrial analogue TV, the satellite video, audio and Teletext streams are separate from each other. When a receiver with Teletext support detects the Teletext stream (PID), it will add it to the field lines of the picture to enable Teletext viewing from a Teletext compatible TV. EPG – Electronic Programming Guide is a useful feature to determine what is on next or at a later stage. Most satellite channels provide what is currently on and the next programme. Some channels even provide the schedule up to a week or two ahead. Some satellite receivers allow the user to choose programmes to record. Once a chosen programme time has reached the receiver changes over to the appropriate channel for the duration of the programme. Diseq – Diseq is a signalling system which the receiver sends out to control Diseq switches and Diseq based motorised dishes. Diseq v.1.0 can operate either a 2-way or 4-way Diseq switch. Diseq v.1.2 operates a low power Diseq 1.2 motor with dish sizes up to around 1 metre. PVR – PVR support allows the satellite receiver to function in the same way as a TV based PVR. With PVR support, the user can pause live broadcasts as well as select EPG programmes or a scheduled times to watch later. Note that PVR systems usually have two cables from the dish. One is for live viewing and the other is for the PVR, which allows the user to watch one channel while recording another. PVR systems with only one input will not allow the user to change channel while it is recording a programme. 36 Volt Output – Receivers with a 36 volt out allow the motorised control of a large motorised dish setup with a separate power cable to the motor. The advantage of having the power supply built in is that the user does not need to operate a separate power supply to move the dish.