Repair manual
1-7
GENERAL DESCRIPTION
1. Monitor Board
The Monitor Board contains the electronics that control the characteristics of
thet CRT - horizontal and vertical deflection, high voltage, luminance, COS
4
exposure correction, focus, and the digital video cathode driver.
2. Logic Board
The Logic Board provides the communications link - receiving and confirming
signals from the host computer. It contains the Centronics Board for parallel
interface and a microprocessor for controlling all memory. The microprocessor
utilizes a Video RAM (V RAM) for exposing the image and Dynamic RAM (D
RAM) for storing picture information that it receives from the computer. In the
Model CI-3000, there is 128K of memory in both V RAM and D RAM, and up to
2K horizontal imaging resolution. The Model CI-5000 has 256K of V RAM,
640K of D RAM, and up to 4K horizontal imaging resolution.
The Logic Board also stores the actual program memory via an EPROM that has
128K of memory; digitally controls vertical deflection up to 4K lines; assures
consistent exposure on every image by digitally controlling autoluminance;
controls the filter wheel, LED (blinks during exposure), and camera back
connection all of which are located on the front panel; it utilizes a frequency
synthesiser to control the system’s resolution — from 256K in the CI-5000,
and from 256K to 2048K in the CI-3000.
3. SCSI Board
The SCSI Board connects to the Logic Board for Macintosh interface.
4. Power Supply Board
The Power Supply Board provodes +5V and +12V and automatically switches
from 110VAC to 220VAC at 50/60Hz.
5. CRT
The CRT is a flat-faced tube which presents a medium-resolution monochrome
black-and-white image. Its normal orientation is rotated 90
o
around the viewing
axis. This means that the horizontal axis is oriented up-and-down and the vertical
axis is oriented side-to-side—as viewed from the front of the recorder.
6. Stepper Motor
The Stepper Motor is regulated by signals from the Logic Board, moves the filter
wheel during the exposure sequence. The filter wheel contains three filters
of the primary colors - red, green, and blue.