Alcad head station
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Areas of application.
In many countries it is required by law to provide for residents of multi-family houses terrestrial TV signals. Apartment buildings, boarding houses, hotels etc. usually have to be equipped with single set of antennas. Use of channel amplifiers and headend station makes it possible to keep good look of facades and enables every user to get access to terrestrial and satellite TV signals.
Headend station manufactured by Alcad company consists of set of panels which allow:
- Receiving of terrestrial analog television
- Receiving of terrestrial digital television (DVB-T)
- Receiving of digital and analog satellite programs
- Distribution of satellite signals to owners of satellite receivers
1.1 Distribution of terrestrial analog signals
Terrestrial TV analog signals should be distributed in community installations (MATV/SMATV systems) with the use of channel amplifiers, or - additionally - channel converters. The solution with converters should be used for big size installation where it is not recommended to distribute the signals on the same channels on which they are broadcast, or - due to older installation - there is the need of converting channels from V band to lower channels.
In big-size installation there may occur parasite signals which will effect in generation of reflections. Besides that, use of conversion allows to change the original signals into channels lying in lower bands - it is needed for installations using older cabling not suitable for work in the UHF band or its higher part.
1.2 The set of terrestrial TV converters and channel amplifiers:
- Frame: ZP-004 R905514
- AC/DC adapter: AS-102 (for twelve ZG R90500 inserts)
- Channel converter: CO-405 R905079
- Channel converter CO-705 R905080
- Channel amplifier: ZG-201 R90512
- Channel amplifier: ZG-401 R90517
- Channel amplifier: ZG-601 R90538
- Connection bridge: ZP-002 R90552
- Terminating resistor (75 ohm): RM-075 R90504
Fig.1. Terrestrial TV converters CO-405/705 and channel amplifiers ZG-601/401
Fig.2. Channel amplifiers ZG-401, ZG-601, ZG-201
2.1 DVB-T receivers.
In many countries there is seen expansion of terrestrial digital television. Digital systems allow distribution a few quality digital TV channels transmitted on previous single analog channel, with the use of current RF technology.
The task of OFDM-PAL receivers/converters is to receive and convert digital signal to analog form to make it possible to distribute it in community antenna installation, to be received with standard televisions. The set should contain number of panels adequate to the number of channels that are to be distributed.
2.2 The collection of modules for reception and distribution of DVB-T broadcasts:
Fig 3. The set of OFDM-PAL receivers
3.1 The set of satellite receivers. In community installation there can be also distributed satellite programs. The proposal of Alcad is the set of digital panels TP-561/TP-544. Single panel is used for receiving one digital program. Head station is an alternative to a multiswitch installation. Such a solution is dedicated to hotels and boarding houses, because it eliminates necessity of having satellite receivers inside guest rooms.
3.2 The set of digital satellite receivers:
Fig.4. The set of QPSK / PAL receivers (for BG: TP-561)
4.1 Satellite IF/IF converters.
In case of apartment buildings where the number of outlets is greater than 100, it is reasonable to install IF/IF converters. This solution allows to select interesting transponders from a few satellites and to place them within satellite intermediate frequency band. In this case, it is required for the installation to work up to 2150 MHz.
Such solution requires for the subscribers to have satellite receivers. There are two types of Alcad panels, both of them include two converters; UC-221 has only one input and loopthrough output, UC-222 - two inputs without a loopthrough. This way it is possible to distribute odd number of transponders from relevant output of Quatro converter.
4.2 The set of IF/IF converters:
Fig.5. The set of IF/IF converters: UC-222, UC-221
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