Digital headends distributing satellite channels converted to DVB-T COFDM form have become popular solutions in hotels. The TERRA system has been designed for building TV distribution installations providing signals to standard televisions with built-in DVB-T tuners and allowing reception of terrestrial (DVB-T) and satellite (DVB-S/S2) channels without additional receivers/STBs. The output RF signals in the single DVB-T COFDM standard are distributed to outlets in rooms via typical coaxial cabling.
Podrobný popis
Terra TDX-420C R81619 DVB-S/S2 to DVB-T transmodulator is used for reception of DVB-S/S2 (8PSK/QPSK) signals, selection of desired channels and retransmission of them in COFDM format in chosen RF channels in VHF/UHF frequency range. The device allows the user to receive and manage a range of free to air and encrypted satellite channels (CI/CAM compatibility). One TDX-420C R81619 panel can receive channels from two satellite transponders and convert them into two neighboring DVB-T multiplexes with maximum throughput of 31.66 Mbps. In practice, each multiplex can carry 6 SD channels or 2-3 HD channels. The administrator of the system selects the required channels from the satellite streams and forms two DVB-T multiplexes. Alternatively, one DVB-T multiplex can be programmed from channels coming from two different satellite transponders. In each case, it is neceeesary to remember about 10% safety margin when determining the maximum bit rate for the whole multiplex (typically the ultimate bit rate of a multiplex should not exceed 29 Mbps). When a higher throughput is required, the system should be equipped with additional TDX-420C R81619 unit(s). The output DVB-T COFDM multiplexes are usually distributed to users by a passive network composed of RF splitters/taps. Such a solution is especially convenient in modern hotel TV systems distributing a variety of satellite channels, including HD broadcasts.
Thanks to RJ-45 Ethernet port, the programming of the TDX-420C R81619 panel is performed via a web browser.
The TDX-420C R81619 panel has two CI slots that in the case of receiving encrypted programs must be equipped with suitable conditional access modules (CAM) with dedicated smart cards.
A great advantage of the Terra device is easy integration with other components:
- dSCR/Unicable multiswitches, allowing for independent distribution of DVB-S/S2 channels via one coaxial cable,
- IPTV streamers for management and distribution of satellite, terrestrial and cable DVB channels within Ethernet (LAN) networks based on twisted-pair cabling,
- optical transmitters for transmission TV programming via optical links,
- other receiving and signal processing devices (broadband and channel amplifiers, analog and digital modulators).
DIPOL offers the following transmodulators of DVB-S/S2 (8PSK, QPSK) signals:
TDX-410C | TDX-420 | TDX-420C | TDQ-420 | TDQ-420C | |
![]() | ![]() | ![]() | ![]() | ![]() | |
Code | R81617 | R81618 | R81619 | R81638 | R81639 |
Input signals | DVB-S/S2 (8PSK, QPSK) | DVB-S/S2 (8PSK, QPSK) | DVB-S/S2 (8PSK, QPSK) | DVB-S/S2 (8PSK, QPSK) | DVB-S/S2 (8PSK, QPSK) |
Number of transponders | 1 | 2 | 2 | 2 | 2 |
Output signals | DVB-T COFDM | DVB-T COFDM | DVB-T COFDM | DVB-C QAM | DVB-C QAM |
Number of MUXes | 1 | 2 | 2 | 2 | 2 |
Max. bitrate [Mb/s] | 31.66 | 2x31.66 | 2x31.66 | 2x53 | 2x53 |
CI slot(s) | 1x | no | 2x | no | 2x |
Key features
- conversion of DVB-S/S2 signals to DVB-T COFDM standard,
- conversion of multiple channels from two satellite transponders to 2 neighboring DVB-T multiplexes,
- possibility to create one DVB-T multiplex from two different satellite transponders,
- selectable channels and services,
- easy control via RJ-45 port,
- two CI ports (multi-channel descrambling of pay-TV)
- management via the Internet,
- access to event history (logs),
- automatic gain control (AGC).

View of the information window of TDX-420C R81619 module
(among others DVB-S2 input RF levels, SNR, VBER parameters)

The use of the output bitrates
Notice: The transmodulator is compatible only with CI CAM modules (no support for CI+).
Specifikace
Typ zboží | Transmodulator | ||
Název | tdx420c | ||
Značka | TERRA | ||
Conversion | DVB-S/S2--->DVB-T | ||
RF input | Number of supported transponders | 2 | |
0/13/18 V & 22 kHz, max. 1 A,DiSEqC 1.0, EN50607, EN50494 | |||
DVB-S2 | |||
QPSK, 8PSK, APSK 8/16/32 | |||
FEC | 8PSK: 3/5, 2/3, 3/4, 5/6, 8/9, 9/10, QPSK: 1/2, 3/5, 2/3, 3/4, 5/6, 8/9, 9/10 | ||
DVB-S | |||
QPSK | |||
FEC | 1/2, 2/3, 3/4, 5/6, 7/8 | ||
Ms/s | 2...45 | ||
dBµV | 45...85 | ||
Ω | 75 | ||
dB | -1 ± 1 | ||
RF input | Number of F-connectors | 1 | |
MHz | 950...2150 | ||
Channels | Ano | ||
Channels | TAK (2 × ) | ||
RF output | DVB-T/ISDB-T | ||
RF output | Number of DVB-T MUXes | 2 (nearby) | |
DVB-T: QPSK, QAM16, QAM64, ISDB-T: QPSK, DQPSK, QAM16, QAM64 | |||
MHz | 100...858, step 100 kHz | ||
dBµV | 90 | ||
dB | 0...15 with step 1 dB | ||
Ω | 75 | ||
MER | dB | ≥38 (100...780 MHz), ≥35 (780...860 MHz) | |
MHz | 7,8 | ||
1/4, 1/8, 1/16, 1/32 | |||
FEC | 1/2, 2/3, 3/4, 5/6, 7/8 | ||
2K | |||
RF output | Mbps | 2 × 31,67 | |
RF combiner | MHz | 47...862 | |
RF combiner | F | ||
Ztráty | dB | 2,5 | |
General | |||
Configuration | RJ-45 (web browser) | ||
Configuration | 192.168.1.10 | ||
Ano | |||
Current drawn | V/A | DC 12/0.55 | |
Provozní teplota | °C | 0...+50 | |
Weight | kg | 0,9 | |
Rozměry | mm | 48,5 × 198 × 112 |