Installation And Operation; Introduction; Installation; General - Tektronix 4023 Service Manual

Section 1-4023 Service
INSTALLATION
AND OPERATION
This manual is a part of the following set of documents
which describe the 4023 Refreshed Computer Display
Terminal:
4023 USERS MANUAL, Tektronix Part No.
070-1621-00.
Contents-An explanation of how to operate and pro-
gram the 4023.
4023 SERVICE MANUAL, Tektronix Part No.
070-1617-00.
Contents-A comprehensive explanation of the 4023. It
includes operation, characteristics, servicing, adjustment,
circuit description, and parts lists.
Optional items used with the Terminal are explained in
separate manuals.
INTRODUCTION
The 4023 Computer Display Terminal interfaces be-
tween man and computer by permitting inputs through an
integral keyboard and providing a display of computer
output data. In addition, the Terminal can relay data
bi-directionally between peripheral devices and a computer.
An Interface Unit must be installed in the Terminal and
connected to the computer-either directly or through a
modem (modulator-demodulator)-to permit information
interchange. The Terminal has the ability to have copies
made of its display, via a Hard Copy Unit.
INSTALLATION
GENERAL
Installation consists of desk-mounting the Terminal,
selecting the proper operating voltage and fuse size, setting
the desired strap options, and connecting the Terminal to
the computer. These steps are discussed in the following
paragraphs.
MOUNTING THE TERMINAL
Desk-Mounting consists of simply setting the Terminal
on a desk or other surface. The air vents on the bottom and
sides should be kept free of obstructions to permit air flow
through the unit.
A dimensional drawing is provided in Fig. 1-2 as an
installation aid.
REV. S, Dl:C. 1974
CIRCUITRY ACCESS
The display unit cover must be removed to permit access
to the Motherboard into which the Terminal Control cards,
interface cards, and optional accessory cards are installed.
Removing the display unit cover opens a line voltage safety
interlock switch, which automatically cuts power when the
cover is removed. The switch actuator (located, in the top,
left-rear corner) can be pulled up to permit Terminal
operation with the display unit cover removed.
I
WARNING
I
Dangerous voltages exist in the display unit area when
the line cord is connected. Servicing should be done
only by qualified technicians.
SELECTING STRAPPABLE OPTIONS
Strappable options are movable wire straps located on
circuit cards inside the display unit, Figs. 1-3 and 1-4 show
the strap option locations. These straps provide options for
the operator and programmer and can be set at the user site
by qualified technical personnel. The circuit cards (seven of
them) plug into the Motherboard. See Fig. 1-5 for card
locations on the Motherboard.
1. Do not remove or install circuit cards while the
Terminal power is on.
2. The cards must be installed in the order shown in
Fig.
1-5;
otherwise, heat is not dissipated properly.
The positions of the straps are dependent upon com-
puter and program requirements, and in some cases, upon
user preference. The location and description of the
movable strap options for the Keyboard Interface, Control,
Timing, and Basic Data Communications I nterface cards are
shown in Figs. 1-3 and 1-4. Information on cut-strap
options can be found in Section 2 of this manual. The
Optional Data Communications Interface (021-0112-00) is
to be installed in P8. The Standard Data Communications
Interface (021-0111-00) is installed in P9. Detailed strap-
pable option information for these two interfaces can be
found in their respective manuals.
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