Operating Information; Features; Controls And Connectors; Safety Information - Tektronix 7844 Instruction Manual

OPERATING INFORMATION

FEATURES

The TEKTRONIX 7844/R7844 is a sOlid-state, wide
bandwidth, dual-beam oscilloscope. The instrument accepts
TEKTRONIX 7000-Series plug-in units to form a complete
measurement system. The flexibility of the plug-in feature
and variety of plug-in units available allow the system to be
used for many different measurement applications.
The 7B44/R7844 provides separate vertical and horizon­
tal deflection systems in addition to FOCUS, INTENSITY,
and BEAM FINDER functions for each beam. The plug-in
unit in either vertical compartment can be selected to pro­
vide vertical deflection for either beam. The plug-in units in
either horizontal compartment may be selected to provide
horizontal deflection for either beam.
The 7844/R7844 features regulated dc power supplies to
ensure that the performance is not affected by variations in
line volta';le and frequency, or by changes in load due to
varying power requirements of the plug-in units. The
7844/R7Ei44 operates from a 1 1 5 V or 230 V (50 Hz to
400 Hz) nominal line source.
X
Other features include a dual-gun full-overlap crt with a
a
graticule area of 8 1 0 centimeters. The instrument also
provides crt display of alphanumeric information encoded
by the plug-in units. The READOUT display indicates plug-in
unit status such as deflection factor, sweep rate, and other
plug-in dE!pendent parameters.
The Option 21 instrument is basically the same as the
standard 7844/R7844 except that the vertical deflection
system is dedicated . The amplifier unit in the LEFT VERT
compartment controls the vertical deflection of beam 1 and
the amplilier unit in the R IGHT VERT compartment controls
the vertical deflection of beam 2. The VERTICAL MODE
switch and VERT SEP control have been deleted . Refer to
the Options section for details.

CONTROLS AND CONNECTORS

Figures 2-1 and 2-2 show the front and rear panels. A
brief description of each control and connector is given. Re­
fer to Detailed Operating Information in the 7844/R7844 Op­
erators manual for additional operating information.
R EV JUN 1 981
Section 2-7844/R7844 Service

Safety Information

This service manual contains warning and caution infor­
mation, which the user must follow to ensure safe operation
of the instrument. Warning information is intended to protect
the operator and Caution information is intended to protect
the instrument.
W A R N I N G
This instrument is intended to
gle-phase earth-referenced power source having one
current-carrying conductor (the Neutral Conductor)
near earth potential. Operation from power sources
where both current-carrying conductors are live with
respect to earth (such as phase-to-phase on a three­
wire system) is not recommended, since only the Line
Conductor has over-current (fuse) protection within
the instrument.
This instrument has a three-wire power cord with a
three-terminal polarized plug for connection to the
power source and safety-earth. The safety-earth ter­
minal of the plug is directly connected to the instru­
ment frame. For electric-shock protection, insert this
plug only in a mating outlet with a safety-earth contact
or otherwise connect the frame to a safety-earth sys­
tem. The color coding of the cord conductors is in
accordance with recognized standards.
Power Cord Conductor Identification
Conductor Color
Ungrounded (Line) Brown
Grounded (Neutral) Blue
Grounding (Earthing) Green-Yellow

Operating Voltage

The 7844/R7844 has a VOLTAGE SELECTOR switch
that allows selection of either a 1 1 5 V or 230 V nominal line
voltage source. When changing the Voltage Selector switch
position, disconnect the power cord and use a small
screwdriver to move the Voltage Selector switch to the de­
sired range.
be
operated from a sin­
Alternate Color
Black
White
Green-Yellow
2- 1