User's Manual

Innovator CU5-1800BTD/BRD ATSC Transmitter/ System Description
Regenerative Translator
Instruction Manual, Rev. 0 36
System Description
The Innovator CXB Series Systems are of two different types. They are either
Regenerative Translators, example: CU100BRD (1312187), or DTV Transmitters,
example: CU100BTD (1312180). The Regenerative Translator (BRD) accepts an RF On
Channel signal (-79 to –8 dBm) and converts it to a DTV RF On Channel output signal.
The DTV System (BTD) takes a SMPTE-310 Input and converts it to a DTV RF On
Channel output signal. The output power level of either configuration is at 10, 30, 50,
100 or 125 Watts ATSC using a single tray, at 250 or 500 Watts ATSC using an
additional single amplifier tray, at 1000 Watts ATSC with two Amplifier trays, at 1500
Watts ATSC with three Amplifier trays, or at 1800 Watts ATSC with four Amplifier trays.
The Innovator CXB Series system provides linear and nonlinear correction capability for
the transmission path as well as internal test sources that are used during initial system
installation.
The CU5-CU125 Innovator CXB Series systems and the CU50 driver tray for higher
power systems contain the Digital Modulator w/Power Conditioner (1309629) that is
made up of (A2) the Digital Modulator Board (1304883) and (A22) the Power
Conditioner Board (1309404). The tray also contains (A3) the IF Precorrector Board
(1308796), (A4) the Frequency Agile Upconverter (1309695), and (A6) the Amplifier
Assembly. The (A7) Output Detector Board (1308685 or 1312207), (A8) the Innovator
CX Control Board (1312543), (A9) the +5V, ±12V Power Supply and (A10) the
+24V/+28V/+32V/+39VDC Power Supply are also contained in the tray. The BRD kit
(1310182) supplies the (A1) 8 VSB Demodulator Board (1308275) to the tray to make it
a regenerative translator.
The type of (A6) Amplifier Assembly used changes as the output power of the system
changes. The Amplifier Assembly (1309621) is used in CU5 systems, the Amplifier
Assembly (1312566) is used in CU30 and CU50 systems and the Amplifier Assembly
(1312191) is used in CU100 and CU125 systems.
The (A10) Power Supply Assembly also changes as the output power of the system
changes. A +24V Power Supply is used in CU5 systems, a 28V 300W Power supply is
used in CU30 Systems, a +36V/600W Power Supply operating at 30V is used in CU50
systems and a +42V/1100W Power Supply operating at 39V is used in CU100 and
CU125 systems.
To operate as an ATSC Transmitter (BTD), the SMPTE-310 input at (J1) connects directly
to the input jack (J42) on the (A2) Digital Modulator Board (1304883). To operate as a
Regenerative Translator (BRD), the DTV ON Channel RF Input at (J1), (-8 to -79 dBm)
connects to the Tuner Input Jack on (A1) the 8 VSB Modulator Board (1308275)
supplied with the (BRD) kit. The 8 VSB Modulator Board (1308275) converts the DTV
input to a SMPTE-310 output at (J13) that connects to the input jack (J42) on the (A2)
Digital Modulator Board (1304883). The rest of the tray operates the same for both the
BRD and the BTD system. The IF output of the 8 VSB modulator board connects to J2
on the IF pre-corrector board (1308796). The IF Pre-Corrector Board provides ALC,
automatic or manual, gain control of the IF level. The board also supplies pre-correction
Response, In Phase and Quadrature Non-Linear adjustments. The board has the
circuitry for ALC Fault, Input Fault and Modulation Fault monitoring and indications. The
IF is connected to the digital upconverter board (1309695) that takes the 44 MHz or 36
MHz IF signal and converts it to a TV channel frequency in the range of 54-860 MHz.
The RF on channel signal is fed to the ALC Board, Innovator CXB Series (1308570),
which is used to control the drive power to the RF amplifier chain in the CU5, CU30,
CU50, CU100 and CU125 Transmitter/Translators. In a CU30 or CU50, the RF is