Tektronix 7704A User manual

INSTRUCTION
- MIAN UAL
Tektronix, Inc.
~ 070-1402-00
e P.O. Box 500 @
Serial Number
Beaverton, Oregon 97005 -® Phone: [phone] -@ Cables: Tektronix
672

‘e you eS
ease include the instrument T pe Number or Part
4
972 by Tektronix, Inc., Beaverto Oregon.
the United States of America. All rights reserved.

Tektronix
COMMITTED TO EXCELLENCE
WARRANTY
NOTICE
THIS WARRANTY SUPERSEDES ANY
OTHER WARRANTY PUBLISHED FOR THIS
PRODUCT PRIOR TO JANUARY 1, 1980.
WARRANTY
Tektronix warrants that this product is free from defects in materials
and workmanship. The warranty period is one (1) year from the date
of shipment. Tektronix will, at its option, repair or replace the
product if Tektronix determines it is defective within the warranty
period and if it is returned, freight prepaid, to a service center
designated by Tektronix.
Tektronix is not obligated to furnish service under this warranty
a. to repair damage resulting from attempts by personnel other
than Tektronix representatives to install, repair, or service the
product;
b. to repair damage resulting from improper use or from
connecting the product to incompatible equipment;
c. if personnel other than Tektronix representatives modify the
hardware or software.
There is no implied warranty of fitness for a particular purpose.
Tektronix is not liable for consequential damages.
Warranty 2

SECTION 1
7704A Operators
TABLE OF CONTENTS
OPERATING INSTRUCTIONS
Preliminary Information
Operating Voltage
Operating Temperature
Plug-In Units
Installation
Interchanging Plug-ins
Controls and Connectors
Front-Panel Color Coding
Location (Fig. 1-2A & B)
Operating Checkout (and Familiarization)
Simplified Operating Instructions
Single-Trace Displays
Dual-Trace & Dual-Sweep Displays
Delayed Sweep Displays
X-Y Displays
Detailed Operating Information
Intensity —F ocus—Astigmatism Controls
BEAM FINDER Switch
CONTROL ILLUM Switch
Trace Alignment
Graticule, Light Filter
Readout System
Vertical and Horizontal Mode
Logic
VERTICAL MODE Switch
HORIZONTAL MODE Switch
Vertical Trace Separation
TRIGGER SOURCE Switches
Intensity Modulation (Z-Axis)
CALIBRATOR Output
Signal Outputs
Probe Power
Page
1-1
1-2
1-2
1-2
1-3, 1-4
15
1-8
1-8
1-9
19
1-9, 1-10
1-10
1-10
1-10
1-10
1-11
1-12
1-13
1-14
1-15
1-15
1-15
1-15
1-16
1-17
SECTION 1
OPERATING INSTRUCTIONS (cont)
Remote Single-Sweep Reset
Display Photography
Applications (Plug-In Combinations)
Vertical Amplifier Plug-Ins
Time-Base Plug-Ins
X-Y Operation
Raster Displays
Sampling Displays
Special-Purpose Plug-Ins
SECTION 2 SPECIFICATIONS
Electrical Performance Requirements
(7704A Only)
Vertical Deflection System
Triggering
Horizontal Deflection System
Calibrator
Character Readout (Optional)
Signal Buffer (Optional)
Vertical Signal Output
Z-Axis Input
+ Sawtooth Output
+ Gate Output
Remote Reset Input (Single-Sweep)
Cathode Ray Tube (CRT)
Power Supply
Environmental Characteristics
Physical Characteristics
Instrument Options
Standard Accessories
System Electrical Characteristics
Page
1-17
1-18
1-18
1-18
1-19
1-19
1-19
2-1
2-1
2-1
2-2
2-2
2-2
2-2
2-2
2-3
2-3
2-3
24
2-4
2-4
24
25
25

nese? SRT
7704A Oscilloscope System.
INTRODUCTION
The TEKTRONIX 7704A Oscilloscope System is a
solid-state, high performance instrument designed for gen-
eral applications. (For rise time and bandwidth specifica-
tions of oscilloscope systems using the 7704A, see page
2-5.) The system is composed of two individual units, the
A7704 Acquisition Unit and the D7704 Display Unit.
The A7704 Acquisition Unit has four plug-in compart-
ments. The left pair of plug-in units is connected to the
vertical system; the right pair is connected to the horizontal
system. Electronic switching between the plug-ins con-
nected to each system allows a dual-trace vertical display
and/or a dual-sweep horizontal display.
7704A Operators
The D7704 Display Unit features a CRT with small spot
size and high writing rate. In addition to the waveform, the
CRT can also display alpha-numeric information from the
plug-in units, such as deflection factor, sweep rate and
other encoded parameters. Standard graticule size is 8 X
10 cm.
DC supplies in the Acquisition Unit supply power for
the entire instrument. These supplies are regulated to assure
that performance is not affected by variations in line
voltage and frequency, or by changes in load due to the
varying power requirements of the plug-in units.

Section 1—7704A Operators
OPERATING INSTRUCTIONS
General
To effectively use this instrument, the operation and
capabilities of the instrument must be known. This section
describes the operation of the front- and rear-panel controls
and connectors and gives general operating information.
PRELIMINARY INFORMATION
Operating Voltage
The 7704A can be operated from either a 115-volt or a
230-volt nominal line voltage source. The Line Selector
assembly on the rear panel converts this instrument from
one operating voltage to the other. This assembly also
includes line fuses. Use the following procedure to obtain
correct instrument operation from the line voltage
available.
OLLI IOS
? CAUTION
This instrument is designed for operation from a
power source with its neutral at or near earth
(ground) potential with a separate safety-earth con-
ductor. It is not intended for operation from two
phases of a multi-phase system, or across the legs of a
single-phase, three-wire system.
1. Disconnect the instrument from the power source.
2. Loosen the two captive screws which hold the cover
onto the selector assembly; then pull to remove the cover.
3. To convert from 115-volts to 230-volts nominal line
voltage, or vice versa, pull out the Selector switch bar (see
Fig. 1-1) and plug it back into the remaining hole. Change
the line-cord power plug to match the power-source
receptacle or use a 115- to 230-volt adapter.
Power Cord Conductor Identification
Conductor Color Alternate Color
Ungrounded (Line) Brown Black
Grounded (Neutral) Blue White
Grounding (Earthing) |Green-Yellow | Green-Yellow
REV... C, NOV... 1976
Indicator
Tab
Captive
Screws
Selector
Switch bar
Fig. 1-1. Line Selector assembly on rear panel (shown with cover
and
fuses removed).
4. Re-install the cover and tighten the captive screws.
5. Before applying power to the instrument, check that
the indicator tab on the switch bar is protruding through
the correct hole for the desired line voltage range.
s WII I TTI TIS)
3 GA UTION
This instrument may be damaged if operated with the
Line Selector assembly set to incorrect positions for
the line voltage applied.
The 7704A is designed to be used with a three-wire AC
power system. If the three- to two-wire adapter is used to
connect this instrument to a two-wire AC power system, be
sure to connect the ground lead of the adapter to earth
(ground). Failure to complete the ground system may allow
the chassis of this instrument to be elevated above ground
potential and pose a shock hazard.
1-1

Operating Instructions—7704A Operators
Operating Temperature
The 7704A can be operated where the ambient air
temperature is between O°C and +50°C. This instrument
can be stored in ambient temperatures between —55°C and
+75°C. After storage at temperatures beyond the operating
limits, allow the chassis temperature to come within the
operating limits before power is applied.
The 7704A is cooled by convection air flow through the
instrument. Adequate clearance must be provided on all
sides to allow heat to dissipate. Do not block or restrict the
air flow through the holes in the cabinet. Maintain the
clearance provided by the feet and allow about two inches
clearance on the top, sides and rear (more if possible).
Operating Position
A bail-type stand mounted on the bottom of the
instrument permits the 7704A to be tilted up about 10° for
convenient viewing.
PLUG-IN UNITS
General
The 7704A accepts up to four TEKTRONIX 7-series
plug-in units. This plug-in feature allows a variety of display
combinations and also allows selection of bandwidth,
sensitivity, display mode, etc. to meet the measurement
requirements. In addition, it allows the oscilloscope system
to be expanded to meet future measurement requirements.
The overall capabilities of the system are determined by
the characteristics of the plug-ins selected. Some typical
combinations are given under ““Applications’” on page 1-18.
along with simplified instructions for setting them up. For
information on other plug-ins, see the current Tektronix,
Inc. catalog.
Installation of Plug-In Units
CAUTION
Plug-in units should not be installed or removed
without first turning the instrument power off, to
prevent instrument damage.
To install a plug-in unit into a plug-in compartment,
align the slots in the top and bottom of the plug-in with the
associated guide rails in the plug-in compartment. Push the
plug-in unit firmly into the plug-in compartment until it
locks into place. To remove a plug-in, pull the release latch
on the plug-in unit to disengage it and to pull the unit out
of the compartment.
1-2
All the plug-in compartments do not need to be filled to
operate the instrument; the only plug-ins needed are those
required for the measurement to be made. At environ-
mental extremes, excess interference may be radiated into
the instrument through the open plug-in compartments.
Blank plug-in panels are available from Tektronix, Inc. to
cover the unused compartments; order TEKTRONIX Part
No. 016-0155-00.
Interchanging Plug-ins
When the instrument is calibrated as directed in the
Service Manual’s Calibration procedure, the vertical and
horizontal gains are normalized, allowing calibrated plug-in
units to be interchanged from one compartment to another
without recalibration. However, the basic calibration of the
individual plug-in units should be checked when they are
installed in this system to verify their measurement
accuracy. See the operating instructions section of the
plug-in unit instruction manuals for verification procedure.
CONTROLS AND CONNECTORS
The major controls and connectors are located on the
front panel of the instrument. Several auxiliary functions
are provided on the rear panel. Figure 1-2 shows the front
and rear panels and provides brief descriptions of each
control and connector. More detailed operating information
is given under ‘Detailed Operating Information’ starting on
page 1-9.
Front-Panel Color Coding
Portions of the front-panel of the 7704A and its plug-in
units are color-coded as follows to aid in operating the
instrument:
RED
Identifies the nomenclature and controls that will
uncalibrate the instrument.
BLUE
Identifies the controls affecting the CRT display mode.
GREEN
Identifies all trigger controls.
Other colors such as gray, orange, yellow, etc. have no
functional assignments, but are used as needed to indicate
the relationship between the appropriate controls and
connectors.
REV. B, NOV. 1977

Operating Instructions—7704A Operators
ASTIG Screwdriver adjust-
ment to obtain a well-defined
display. Does not require re-
adjustment in normal use.
BEAM FINDER Compresses
and defocuses display within
graticule area regardless of dis-
play position or applied signal.
TRACE ROTATION Screw-
driver adjustment to align
trace with graticule.
FOCUS Adjustment for opti-
mum display sharpness.
CALIBRATOR Provides cali-
brated 40mV-4V, 1kHz
square-wave signals.
POWER (PULL)
VERTICAL MODE Selects _ lo
i - /r¥0a AOUUISTION UST &
vertical plug-in compart- ‘4 rica na
ment(s) providing the vertical
deflection signal.
VERT TRACE SEPARATION
(B) Vertically positions the B
HORIZ trace with respect to
the A HORIZ trace (dual-
sweep modes only)
A INTEN Controls brightness
of the trace produced by the
A
HORIZ plug-in.
A TRIGGER SOURCE Selects
internal trigger source for A
HORIZ time base.
INTENSITY Controls bright-
ness of the display (except the
readout portion). «
READOUT Controls bright-
ness of the readout portion of
the CRT display. Turns off the
readout system when in the
CCW detent position.
GRAT ILLUM Controls grati-
cule illumination.
B TRIGGER SOURCE Selects
internal trigger source for B
HORIZ time base.
B INTEN Controls brightness
of the trace produced by the B
HORIZ plug-in.
HORIZONTAL MODE Selects
horizontal plug-in compart-
ment(s) providing the hori-
zontal deflection signal.
Fig. 1-2A. Front-panel controls and connectors.
1-3

Operating Instructions—7704A Operators
Z AXIS INPUT Input for Z-
Axis circuit providing inten-
sity modulation of the CRT.
VERT SIG Sample of vertical
signal as selected by B TRIG-
GER SOURCE switch.
+ SAW TOOTH Sample of A
Sawtooth or B Sawtooth as
selected by an internal switch.
+ GATE Square-wave signal as
selected by an internal switch:
A Gate; B Gate; or A Dely’d
Gate.
CONTROL ILLUM Controls
illumination of push-button
switches. :
PROBE POWER Connectors
supplying power to one or two
active probes.
REMOTE RESET INPUT Pro- Line Selector Assembiy Se-
vides remote single-sweep reset lects the nominal line voltage
when Time base is in Single (115 or 230 VAC).
Sweep Mode.
Fig. 1-2B. Rear-panel controls and connectors.