User's Manual

Innovator CU5-1800BTD/BRD ATSC Transmitter/ Board Descriptions
Regenerative Translator
Instruction Manual, Rev. 0 53
transistor operating 90 degrees out of phase of the other, which provides for a very
good return loss across the UHF band on both the input and output of the board.
(A7) Output Detector Board (1308685 or 1312207 in the CU100BTD/BRD)
The (1308685 and 1312207) output detector boards are identical in operation except the
(1312207) board can be used as either an average, for digital, or peak, for analog,
detector board using jumpers on J5 and J6. The (A7) Output Detector Board provides
forward (2V=100%) and reflected (2V=25%) power samples to the CU Control Board for
metering and monitoring purposes. R7 is the reflected power calibration pot and R23 is
the forward power calibration pot. A Forward power sample, -10 dBm, connects to J4 on
the board, which is cabled to the front panel sample jack of the tray. The RF output of
the board, typically +46 dBm, is at J2, which is cabled to J9 the RF Output Jack of the
tray.
(A8) Control Card, Innovator CX (1312543)
The Innovator CX control board provides the overall system control for the CXB system.
There are two main elements of the board, U7 and U9. U7 is a programmable logic
device that is loaded with firmware, which provides the overall system control. It
decides whether or not to allow the system to generate RF output power, and turns the
+32 VDC power supply on and off depending on whether or not it is receiving any faults,
either faults generated on board, or faults generated externally. The second major
component of the board is the microcontroller U9, which controls the front panel
indications and drives the display. The U9 microcontroller is not involved in the decision
making process, U7 does that. Rather, it is layered on top of U7 and is the EPLD's
interface to the outside world. Information is passed between the microcontroller and
the EPLD. The microcontroller communicates information to and from the front panel
and sends the EPLD the information it needs to decide whether or not to allow the
system to turn on. The front panel viewable LEDs DS3 for Operate/Standby and DS4 for
Status indicate the current operating condition of the system are mounted on and
controlled by this board. The U9 microcontroller can also communicate, using the
Optional Ethernet Kit, with a daughter card that allows the user to view remote control
parameters via a web Ethernet interface.
The ±12 VDC and +5 VDC from the (A9) power supply and the +32 VDC from the (A10)
power supply are routed to the other boards in the tray through this board. The +32
VDC power supply operates all the time, and connects the +32 VDC to the board at J19-
1, 2, & 3 with 5 common. Q13 on the control board is turned on and off to gate the +32
VDC, which connects through J19-6, 7 & 8, to the RF output stages.
The ±12 VDC and +5 VDC input voltages to this board is connected through J21 and
filtered before being connected to the rest of the board. +12 VDC connects through
J21-1, +5VDC through J21-2 & 3, and -12 VDC through J21-6. Common connections for
the input voltages are connected to J21-4 & 5. The ±12 VDC and +5 VDC are used on
this board and also routed to the other boards in the tray through this board. The +3.3
VDC for the microcontroller and programmable logic array, mounted on the board, is
provided by the voltage regulator IC U6 from the filtered +5 VDC input. The output of
U6 can be adjusted to +3.3 VDC using R120.