Tektronix TLA 714, Руководство по обслуживанию

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TLA 714 Color Portable Mainframe Service Manual
3–1
Theory of Operation
This section provides a brief overview of the board level theory of operation for
the portable mainframe. Refer to page 6–2 for a functional block diagram.
Portable Mainframe
The portable mainframe contains the following major components:
The power supply provides all voltages and currents to the portable mainframe.
The power supply connects to the backplane at P400 and P401.
The backplane connects the power supply secondary to the remainder of the
system, including the fans, distributes the precision 10-MHz (CLK10) system
clock, and supports all communication between the instrument modules.
The controller board provides the portable mainframe with a high-performance
PC-based controller architecture, and interfaces to the backplane bus and front
panel. The controller board mounts vertically on the left side of the instrument
and connects to the back of the backplane. The controller board provides I/O to
the rear panel and is the source of the 10-MHz (CLK10) system clock.
The front panel interface board interconnects the controller board, the flat-panel
display, the floppy disk drive, the front-panel keypad and glidepoint, dual USB
ports, and the external mouse and keyboard ports. Dual 50-pin cables connect the
front panel interface board to the controller board. The interface board also
supplies the PC speaker.
The front panel controller board combines signals from the front-panel hex
keypad, the front-panel QWERTY keypad, and an external keyboard to generate
or receive standard keyboard scan-codes from the controller board.
The mechanical chassis provides the mechanical support structure for the
instrument, and includes the cooling system, the modular-card cage, the EMI
shielding system, and all the subsystems previously listed.
Power Supply
Backplane
Controller Board
Front Panel
Interface Board
Front Panel Controller
Board
Mechanical Chassis