Tektronix Phaser 840, Service Manual

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Service Guide 9
Seven circuit boards support the printer’s electronics. Two boards, called I/
O boards (left and right), support the front panel, solenoids and sensors. The
main board contains the printer’s CPU processor, RAM and ROM. The power
control board distributes power supply voltages to the other printer boards and
many of the printer motors. The power supply converts the AC line voltage into
internal AC and DC voltages. The front panel provides a user interface to the
printer. The printhead drive board, a part of the printhead, manages the signals
and voltages of the printhead’s printing elements and sensors. The optional
network card and internal hard drive could be considered eight and ninth circuit
boards.
Circuit boards of the print engine (right front view)
0388-03
I/O board
right
Front
panel