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Rack-Mount QPSK to QAM Transmodulators – QT Series

QPSK to QAM Modulation
in a Modular Rack-Mount Chassis

The QT Series is the latest Blonder Tongue Transmodulator product and it features the ultimate combination of optimum balance of price per channel and top notch performance and functionality. This new unit incorporates a scalable modular design that allows from one to eight transmodulator module sections as well as a hot-swappable single combination power supply & control module.

Support for redundant back-up or ‘standby’ power has been built into every QT power supply & control module. This ability is easily added by an operator at any time by interfacing an optional standby power supply unit. The QT Series also has the ability to easily accommodate future upgrades and advances such as such for 8PSK decoding and 256 QAM processing via a specially designed optional QAM Transcoder Module (QTM-HD).

Each QT Chassis can contain up to eight (8) separate QPSK to QAM transcoder modules. Each QAM Transcoder Module (QTM) is fully agile to allow the reception of any Echostar Dish Network™ or Bell ExpressVu DVB based QPSK transponder signal, (ITU-T J.83 Annex A). The module is housed in a specially designed chassis intended to accommodate the transcoder modules. Control of the modules is easily accomplished with a common power supply & control unit via operator selection from the front panel push button controls and back-lit LCD panel. This module interfaces to any of the QAM Transcoder Modules through a simple 12-pin connector and cable. The control module’s brain is a flash upgradeable microprocessor to ensure support for any future development.

Diagram of QPSK - QAM Signal Transmodulation

 

QT Series Specifications

Satellite 8PSK Input

Input Frequency Range: Agile 950-2150 MHz
8PSK Bandwidth: up to 36 MHz
Frequency Step: 1 MHz
Capture Range: ±5 MHz
Input Level Range: -65 to -20 dBm
RF Input Impedance: 75 Ω
Return loss: 8 dB min.
FEC Decoding: DVB
Symbol Rate: 2 to 45 Msps
Code Rate: Viterbi Auto Recognition
I - Q Format: Normal / Inverted

QAM Output

Output Frequency Range: Agile 54-860 MHz (CATV 2-135)
QAM Bandwidth: 6 MHz
Frequency Step: 6 MHz
Output Level: +40 dBmV *
Display Error: ±2 dB
Level Adjustment Range: 15 dB
Modulation Mode: 16, 32, 64, 128, 256 QAM (8PSK & 256 QAM Capable with optional QTM-HD)
Symbol Rate: 1 Msps to 6.9 Msps
Spectral Inversion: Auto Recognition
Carrier Suppression: 45 dB
Roll off: 12, 15, 18 %
QAM SNR: >40 dB
MER: 38 to 41 dB
RF Output Impedance: 75 Ω
Spurious: -60 dBc
Broadband Noise: -75 dBc min. (4 MHz BW @40 dBmV) Phase Noise @ 10 kHz: -90 dBc
Frequency Stability: ± 10 kHz
QAM I/Q Phase Error: < 1 degree
I/Q Amplitude Imbalance: < 1 dB
Controls and Indicators
PCM
Computer Control: 2 RJ11 Rear Panel RS232

Connectors

Backlit Liquid Crystal Display (LCD) 5 Navigation/Enter Push Buttons

QTM Unit Status Indicator: 1 Green LED Per Module

Mechanical

Chassis Dimensions: 5.25 x 19.0 x 12 inches
QTM Dimensions: 5.25 x 10.625 x 1.5 inches
Mounting: Standard EIA Unit Height 5.25” x 19” Wide Rack Mount
QTM Unit Weight: 1.7 lbs
QTM-8 Weight: 28 lbs

Power

Requirement: 100 to 265 VAC, 1A
Frequency: 50 to 60 Hz
Power Consumption:

1 QTM & PCM: 15 W
2 QTM & PCM: 25 W
3 QTM & PCM: 35 W
4 QTM & PCM: 45 W
5 QTM & PCM: 56 W
6 QTM & PCM: 66 W
7 QTM & PCM: 76 W
8 QTM & PCM: 87 W

Fuse: 4 Amp, 250 VDC, SB

Environmental Operating Temperature: 0 to 50 °C
Storage Temperature: -20 to 70 °C
Humidity: 0 to 90 % RH

 

* Average Measurement