Lecroy 9300C User Manual

Operator’s Manual
LeCroy 9300C Series Digital Oscilloscopes
Revision A — January 1998
700 Chestnut Ridge Road Chestnut Ridge, NY 10977–6499 Tel: (845) 578 6020, Fax: (845) 578 5985
LeCroy SA
2, rue du Pré-de-la-Fontaine 1217 Meyrin 1/Geneva, Switzerland Tel: (41) 22 719 21 11, Fax: (41) 22 782 39 15
Internet: www.lecroy.com
Copyright © January 1998, LeCroy. All rights reserved. Information in this publication supersedes all earlier versions. Specifications subject to change.
LeCroy, ProBus and SMART Trigger are registered trademarks of LeCroy Corporation. MathCad is a registered trademark of MATHSOFT Inc. Centronics is a registered trademark of Data Computer Corp. Epson is a registered trademark of Epson America Inc. PowerPC is a registered trademark of IBM Microelectronics. MATLAB is a registered trademark of The MathWorks, Inc. DeskJet, ThinkJet, QuietJet, LaserJet, PaintJet, HP 7470 and HP 7550 are registered trademarks of Hewlett­Packard Company. I
Manufactured under an ISO 9000 Registered Quality Management System Visit www.lecroy.com to view the certificate.
2
C is a trademark of Philips.
This electronic product is subject to disposal and recycling regulations that vary by country and region. Many countries prohibit the disposal of waste electronic equipment in standard waste receptacles. For more information about proper disposal and recycling of your LeCroy product, please visit www.lecroy.com/recycle.
93XXC-OM-E Rev A 0198
Chapter 1 — Read This First!
Product and Client Care..............................................................1–1
Chapter 2 — Instrument Architecture
General Designed Capabilities................................................2–1
Block Diagrams.................................................................................2–4
Chapter 3 — Installation and Safety
Installation for Safe and Efficient Operation...................3–1
Chapter 4 — Introduction to the Controls
The Front Panel.................................................................................4–1
The Main Controls.......................................................................... 4–3
Choosing and Navigating in Menus.......................................4–4
System Setup and Menu Controls..........................................4–6
Screen Topography ........................................................................4–8
Contents
Chapter 5 — CHANNELS, Coupling and Probes
Channel Controls..................................................................... 5–1
Coupling...............................................................................................5–3
Probes and Probe Calibration ..................................................5–4
Chapter 6 — TIMEBASE + TRIGGER
TIMEBASE + TRIGGER Controls..............................................6–1
Chapter 7 — Timebase Modes and Setup
Timebase Sampling Modes........................................................7–1
Timebase Setup ...............................................................................7–5
iii
Chapter 8 — Triggers and When to Use Them
Choosing the Right Trigger .......................................................8–1
Edge or SMART? ..............................................................................8–2
Edge Trigger ......................................................................................8–3
TRIGGER SETUP: Edge................................................................8–9
SMART Triggers.............................................................................8–10
TRIGGER SETUP: SMART ........................................................ 8–29
Chapter 9 — ZOOM + MATH
Zoom and Math Controls............................................................. .9–1
Chapter 10 — Zoom, Mathematics and Math Setup
Zooming for Precise Waveform Measurements...........10–1
Math Functions and Options ..............................................10–2
Using Waveform Mathematics...........................................10–5
Configuring for Zoom and Math.........................................10–6
Setting Up FFT Span and Resolution .............................10–17
Contents
Chapter 11 — Display
Chapter 12 — UTILITIES
Setting Up the Display........................................................ 11–1
Printing, Storing, Using Special Modes ........................... 12–1
Hardcopy Setup............................................................................12–2
Time/Date Setup...........................................................................12–4
GPIB/RS232 Setup.......................................................................12–5
Mass Storage Utilities .............................................................. 12–7
Special Modes ........................................................................ 12–19
CAL BNC Setup.............................................................................12–21
iv
Chapter 13 — WAVEFORM STORE & RECALL
Waveform Store......................................................................13–1
Waveform Recall....................................................................13–4
Chapter 14 — CURSORS/MEASURE & Parameters
Cursors: Tools for Measuring Signal Values.................14–1
Parameters: Automatic Measurements ..........................14–4
Pass/Fail Testing...................................................................14–13
Chapter 15 — PANEL SETUPS
Saving and Recalling Panel Setups...............................15–1
Chapter 16 — SHOW STATUS
The Complete Picture — Summarized............................ 16–1
Appendix A — Specifications Appendix B — Enhanced Resolution Appendix C — Fast Fourier Analysis (FFT) Appendix D — Parameter Measurement Appendix E — ASCII-Stored Files
v
1
Read This First!
Product and Client Care
We recommend you thoroughly inspect the contents of the scope packaging at once. Check all the contents against the packing list/invoice copy shipped with the instrument and the list on page 1–3 of this manual. Unless LeCroy is notified promptly of a missing or damaged item, we cannot accept responsibility for its replacement. Contact your national LeCroy Customer Service Department or local office immediately (contact numbers follow index).
Warranty LeCroy warrants its oscilloscope products for normal use and
operation within specifications for a period of three years from the date of shipment. Calibration each year is recommended to ensure in-spec performance. Spares, replacement parts and repairs are warranted for 90 days. The instrument's firmware has been thoroughly tested and is thought to be functional, but is supplied without warranty of any kind covering detailed performance. Products not made by LeCroy are covered solely by the warranty of the original equipment manufacturer.
In exercising its warranty, LeCroy will repair or, at its option, replace any product returned within the warranty period to the Customer Service Department or an authorized service center. However, this will be done only if the product is determined by LeCroy’s examination to be defective due to workmanship or materials, and the defect has not been caused by misuse, neglect or accident, or by abnormal conditions or operation.
Note: This warranty replaces all other warranties, expressed or implied, including but not limited to any implied warranty of merchantability, fitness, or adequacy for any particular purpose or use. LeCroy shall not be liable for any special, incidental, or consequential damages, whether in contract or otherwise. The client will be responsible for the transportation and insurance charges for the return of products to the service facility. LeCroy will return all products under warranty with transport prepaid.
1–1
Read This First!
Product Assistance Help on installation, calibration, and the use of LeCroy
equipment is available from the LeCroy Customer Service Department in your country (see contact numbers following the index).
Maintenance Agreements We provide a variety of customer support services. Maintenance
agreements give extended warranty and allow our clients to budget maintenance costs after the initial three-year warranty has expired. Other services such as installation, training, enhancements and on-site repairs are available through special Supplemental Support Agreements.
Staying Up to Date LeCroy is dedicated to offering state-of-the-art instruments,
continually refining and improving the performance of our products. Because of the speed with which physical modifications may be implemented, this manual and related documentation may not agree in every detail with the products they describe. For example, there might be small discrepancies in the values of components affecting pulse shape, timing or offset, and — infrequently — minor logic changes.
However, be assured the scope itself is in full order and incorporates the most up-to-date circuitry.
We frequently update firmware or software during servicing to improve scope performance, free of charge during warranty. We will keep you up to date with such changes, through new or revised manuals and other publications.
But you should retain this, the original manual, for future reference to your scope’s unchanged hardware specifications.
Service and Repair Please return products requiring maintenance to the Customer
Service Department in your country or to an authorized service facility. LeCroy will repair or replace any product under warranty free of charge. The customer is responsible for transportation charges to the factory, whereas all in-warranty products will be returned to you with transportation prepaid. Outside the warranty period, you will need to provide us with a purchase order number before we can repair your LeCroy product. You will be
1–2
billed for parts and labor related to the repair work, and for shipping.
1–3
Read This First!
How to Return a ProductContact your country’s Customer Service Department or local
field office to find out where to return the product. All returned products should be identified by model and serial number. You should describe the defect or failure, and provide your name and contact number. And in the case of products returned to the factory, a Return Authorization Number (RAN) should be used. The RAN can be obtained by contacting the Customer Service Department.
Return shipments should be made prepaid. We cannot accept COD (Cash On Delivery) or Collect Return shipments. We recommend air-freighting.
It is important that the RAN be clearly shown on the outside of the shipping package for prompt redirection to the appropriate LeCroy department.
What Comes with Your Scope The following items are shipped
together with the standard configuration of this oscilloscope:
Ø Front Scope Cover Ø 10:1 10 M Passive Probe — one per channel Ø ProBus Single-Channel Adapter (9354C, 9374C, 9384C
SERIES ONLY)
Ø Two 250 V T-rated Fuses (5 A or 6.3 A depending on model
see Chapter 3)
Ø AC Power Cord and Plug Ø Operator’s Manual (this manual) Ø Remote Control Manual Ø Hands-On Guide Ø Performance Certificate Ø Declaration of Conformity Ø Warranty
Note: Wherever possible, please use the original shipping carton. If a substitute carton is used, it should be rigid and packed so that that the product is surrounded by a minimum of four inches or 10 cm of shock-absorbent material.
1–4
2
Instrument
Architecture
General Designed Capabilities
Your oscilloscope is the newest version of a series that set the standard for monochrome DSOs (Digital Storage Oscilloscopes). Each of the scope’s channels has an 8-bit ADC (Analog–to–Digital Converter). On the higher-range models, combining two channels doubles the scope’s sampling rate. While on high-range, four-channel models, combining all channels increases the original rate by four times.
Processors The central microprocessor performs the scope’s computations and
controls its operation. A wide range of peripheral interfaces allow remote control, storage and printing. A support processor constantly monitors the front-panel controls, rapidly reconfiguring setups. Data processing is also rapid, with data being transferred to the display memory for direct waveform display or stored in the reference memories (see below).
Note: Wherever a feature is specific to a particular model, or not included with a model, it is indicated thus: 9314C ONLY, for example. For the complete list of specifications for each model, see the section on that model or its series in Appendix A.
ADCs The instrument’s multiple-ADC architecture ensures absolute
amplitude and phase correlation, maximum ADC performance for multi-channel acquisitions, large record lengths and excellent time resolution.
Memories The copious acquisition memories simplify transient capture by
producing long waveform records that capture even when trigger­timing or signal-speed is uncertain. Combining channels also increases the acquisition memory length. There are four memories for temporary storage, and four more for waveform zooming and processing.
2–1
Instrument
Architecture
RIS Repetitive signals can be acquired and stored at a Random
Interleaved Sampling (RIS) rate of 10 GS/s. RIS is a high­precision digitizing technique that enables measurement of repetitive signals to the instrument's full bandwidth, with an effective sampling interval of 100 ps and measurement resolution of 10 ps. (See Chapter 7).
Trigger System The Trigger System offers an extensive range of capabilities,
selected according to the character of the signal, using on­screen menus and front-panel controls. In standard trigger mode these menus and controls enable the selection and setting of parameters such as pre- and post-trigger recording, as well as special modes. The trigger source can be any of the input channels, line (synchronized to the scope’s main input supply) or external. The coupling is selected from AC, LF REJect, HF REJect, HF, and DC; the slope from positive and negative. (See Chapter 8.)
Automatic Calibration The oscilloscope’s automatic calibration ensures an overall
vertical accuracy of typically 1% of full scale. Vertical gain and offset calibration take place each time the volts/div setting is modified. In addition, periodic calibration is performed to ensure long-term stability at the current setting.
Display System The display’s interactive, user-friendly interface is controlled by
push-buttons and knobs (see Chapter 4). The large, 12.5 × 17.5 cm (nine-inch diagonal) screen shows
waveforms and data with enhanced resolution on a variety of grid styles (see Chapter 11). Up to four waveforms can be displayed at once, while the parameters controlling signal acquisition are simultaneously reported. The screen presents internal status and measurement results, as well as operational, measurement, and waveform-analysis menus.
Printing or copying the screen on plotter, printer or to a recording medium is done by pressing the front-panel SCREEN­DUMP button(See Chapter 12).
2–2
Manual or Remote Control
Despite being a truly digital instrument, the scope has a front­panel layout and controls that will be familiar to users of analog oscilloscopes. Rapid instrument response and instant representation of waveforms on the high-resolution screen add to this impression.
Four front-panel setups can be stored internally and recalled either manually or by remote control, thus ensuring rapid front­panel configuration. When the power is switched off, the current front-panel settings are automatically stored for subsequent recall at the next power-on.
The oscilloscope has also been designed for remote control operation in automated testing and computer-aided measurement applications — operations described in the Remote Control Manual. The entire measurement process, including cursor and pulse-parameter settings, dynamic modification of front-panel settings, and display organization, is controlled through the rear-panel GPIB (IEEE-488) and RS-232-C ports (see Chapter 12).
2–3
Block Diagrams
Program memory
Microprocessor
Storage devices
Ø 9304C, 9310C, 9314C
Instrument
Architecture
Series
Hi-Z, 50 Amplifiers + Attenuators
CH1
CH2
External
trigger
CH3
CH4
W
Sample
& Hold
Sample
& Hold
Sample
& Hold
Sample
& Hold
Trigger
logic
8-bit
Flash ADC
8-bit
Flash ADC
Timebase
8-bit
Flash ADC
8-bit
Flash ADC
Fast
memory
Fast
memory
Fast
memory
Fast
memory
processor
Display
Centronics
RS-232-C
GPIB
Coprocessor
Front-panel
processor
Real-time
clock
Data memories
2–4
Ø 9344C, 9350C, 9354C
Program memory
Microprocessor
Series
Ø 9370C, 9374C Series Ø 9384C Series
Hi-Z, 50 Amplifiers + Attenuators
CH1
CH2
External
trigger
CH3
CH4
W
Sample
& Hold
Sample
& Hold
Sample
& Hold
Sample
& Hold
8-bit ADC
8-bit ADC
Trigger
logic
8-bit ADC
8-bit ADC
Peak
detect
Peak
detect
Timebase
Peak
detect
Peak
detect
Fast
memory
Fast
memory
Fast
memory
Fast
memory
Display
processor
Storage devices
Centronics
RS-232-C
GPIB
Coprocessor
Front-panel
processor
Real-time
clock
Data memories
2–5
3
Installation and Safety
Installation for Safe and Efficient Operation
The oscilloscope will operate to its specifications if the operating environment is maintained within the following parameters:
Operating Environment
Safety Symbols Where the following symbols or indications appear on the
Symbol Meaning
Ø Temperature..........................5 to 40 °C (41 to 104 °F) rated.
Ø Humidity................................Maximum relative humidity 80 % RH
(non-condensing) for temperatures up to 31 °C decreasing linearly to 50 % relative humidity at 40 °C
Ø Altitude ..................................< 2000 m (6560 ft)
The oscilloscope has been qualified to the following EN61010-1 category:
Ø Protection Class.........................................I
Ø Installation (Overvoltage) Category...........II
Ø Pollution Degree.........................................2
instrument’s front or rear panels, or elsewhere in this manual, they alert the user to an aspect of safety.
CAUTION: Refer to accompanying documents (for Safety­related information).
See elsewhere in this manual wherever the symbol is present, as indicated in the Table of Contents.
CAUTION: Risk of electric shock.
x
On (Supply).
3–1
Installation and Safety
Symbol Meaning
Off (Supply)
Earth (Ground) Terminal
Protective Conductor Terminal
Chassis Terminal
Earth (Ground) Terminal on BNC Connectors
Denotes a hazard. If a WARNING is indicated on the
WARNING
WARNING Any use of this instrument in a manner not specified by the
Power RequirementsThe oscilloscope operates from a 115 V (90 to 132 V) or 220 V (180
instrument, do not proceed until its conditions are understood and met.
manufacturer may impair the instrument’s safety protection. The oscilloscope has not been designed to make direct measurements on the human body. Users who connect a LeCroy oscilloscope directly to a person do so at their own risk. Use only indoors.
to 250 V) AC power source at 45 Hz to 66 Hz.
3–2
No voltage selection is required, since the instrument automatically adapts to the line voltage present.
Fuses The oscilloscope’s power supply is protected against short-circuit and
overload by means of two “T”-rated fuses of type according to scope model:
Ø 6.3 A/250 V AC 9344C, 9350C, 9354C, 9370C, 9374C, 9384C Series Ø 5 A/250 V AC 9304C, 9310C, 9314C Series.
The fuses are located above the mains plug. Disconnect the power cord before inspecting or replacing a fuse. Open the fuse box by inserting a small screwdriver under the plastic cover and prying it open. For continued fire protection at all line voltages, replace only with fuses of the specified type and rating (see above).
Ground The oscilloscope has been designed to operate from a single-phase
power source, with one of the current-carrying conductors (neutral conductor) at ground (earth) potential. Maintain the ground line to avoid an electric shock. None of the current-carrying conductors may exceed 250 V rms with respect to ground potential. The oscilloscope is provided with a three-wire electrical cord containing a three-terminal polarized plug for mains voltage and safety ground connection. The plug's ground terminal is connected directly to the frame of the unit. For adequate protection against electrical hazard, this plug must be inserted into a mating outlet containing a safety ground contact.
Cleaning and Maintenance Maintenance and repairs should be carried out exclusively by a LeCroy
technician (see Chapter 1). Cleaning should be limited to the exterior of the instrument only, using a damp, soft cloth. Do not use chemicals or abrasive elements. Under no circumstances should moisture be allowed to penetrate the oscilloscope. To avoid electric shocks, disconnect the instrument from the power supply before cleaning.
CAUTION Risk of electrical shock: No user-serviceable parts inside. Leave
repair to qualified personnel.
Power On Connect the oscilloscope to the power outlet and switch it on by pressing
the power switch located on the rear panel. After the instrument is switched on, auto-calibration is performed and a test of the oscilloscope's ADCs and memories is carried out. The full testing procedure takes approximately 10 seconds, after which time a display will appear on the screen.
3–3
4
Two-Channel Front Panel
Introduction to the
Controls
4–1
Four-Channel Front Panel
Introduction to the
Controls
4–2
The Main Controls
The front panel controls are divided into four main groups of buttons and knobs: the System Setup and menu controls, CHANNELS, TIMEBASE + TRIGGER and ZOOM + MATH.
System Setup Dark-gray, menu-entry buttons, also represented in the other
groups of controls, provide access to the main on-screen menus and the acquisition, processing and display modes of the instrument.
The SCREEN DUMP, SHOW STATUS and CLEAR SWEEPS buttons, respectively: copy or print the screen display, show on­screen summaries of the scope’s status, and restart operations that require several acquisitions. See page 4–6.
Menu Buttons & Knobs The seven untitled buttons vertically aligned beside the screen,
RETURN and the two linked rotary knobs enable on-screen menu selection. See following pages.
CHANNELS This group offers selection of displayed traces and adjustment of
vertical sensitivity and offset. See Chapter 5.
AUTO SETUP This singular blue button automatically adjusts the scope to acquire
and display signals on the input channels. See Chapter 6.
TIMEBASE + TRIGGER These controls allow direct adjustment of time/division, trigger level
and delay, as well as access to the “TIMEBASE” and “TRIGGER” menu groups. See Chapters 6, 7 and 8.
ZOOM + MATH And this group controls trace selection, movement, definition, and
expansion with Zoom and Math functions. See Chapters 9 and 10.
See alsoGetting Started”, Part 2 of the Hands-On Guide , for more on the front-panel and a complete run-through of the controls…
4–3
Introduction to the
entry
Choosing and Navigating in Menus
On-screen menus — the panels running down the right­hand side of the screen — are used to select specific scope actions and settings. All other on-screen text is for information only. The menus are broadly grouped according to function. The name of each menu group is shown at the top of the column of menus. Individual menus also have names in the top of their frames.
Each menu either contains a list of items or options — functions to be selected or variables modified — or when selected performs a specific action. Menus that perform certain actions are indicated by capitalized text, as in the example shown at left.
Controls
Going to Menus and Selecting from them
When a menu­configuration for its particular group of functions is immediately displayed on-screen as a menu group. Once accessed, these menus are controlled using the menu buttons and the two menu knobs (illustrated at left).
A menu button is active and can be pressed to make selections whenever a menu is visible beside it on-screen.
The two menu knobs work together with the two menu buttons to which they are joined by lines. Both control the menus currently shown beside them. Buttons and knobs are used either for selecting entire menus, particular items from menus, for moving up or down through menu lists, or for changing the values listed in menus.
Some menus, referred to as primary, have secondary menus beneath them whose existence is indicated by a heavy outline or shadow, as illustrated at left. Pressing the corresponding menu button reveals and activates these ‘hidden’ menus. Pressing the RETURN button again displays the top, or primary, menu.
Changing a menu value normally changes the screen, because the new value is immediately used in acquisition settings, processing or display.
button is pressed, the set-up
4–4
Setting Menu Options The activated selection is highlighted in the menu. Press the
corresponding menu button and the field will advance to highlight and select the next item on the menu. However, if there is only one item on a menu, pressing its button will have no effect.
Where a menu is associated with one of the two menu knobs, turning this knob in one direction or the other will cause the selection to move either up or down the list in the menu.
Menus that extend along the length of two menu buttons can be operated using both buttons. Pressing the lower of the two will move the highlighting forward — down the list — while pushing the upper will move the selector back up the list.
An arrow on the side of a menu frame indicates that by pressing the button beside this arrow, the selection can be moved further up or down the list. The arrow’s direction shows whether the highlighting selector will move up or down. Arrows may also indicate items that are not visible, either above or below on the list. The respective arrow will disappear when the selection is at the very beginning or end of the list.
As in the examples at left, some menu button and knob combinations control the value of a continuously adjustable variable. The knob is then used to set its value, while the button either selects a value or makes a simple change in it.
Still other menu button and knob combinations control the value of several continuously adjustable variables, with the knob used to set the value and the button to highlight it.
Note: When the oscilloscope is placed in a remote state, the REMOTE ENABLE menu will be displayed. It will contain the command “GO TO LOCAL”, activated by menu button if the action is possible. This is the only manual way to turn off the REMOTE ENABLE menu. The scope need not be in remote state to accept remote commands.
4–5
Introduction to the
System Setup and Menu Controls
As well as the menu buttons and knobs described on the previous pages, the System Setup controls include the menu­entry buttons and others for copying displays, reporting instrument status and restarting multiple-acquisition operations.
The RETURN button is used to go back to the preceding displayed menu group. Or it returns the display to a higher-level, or primary menu. But when the display is at the highest possible menu level, the button switches off that menu.
Each of the dark-gray menu-entry buttons activates a major set of on-screen menus (those represented in the other control groups are
described in the following chapters, along with the other elements in the groups).
The DISPLAY button provides entry to the “DISPLAY SETUP” group of menus, controlling display mode, grids, intensities, Dot Join and Persistence menus. See Chapter 11.
Controls
The UTILITIES button gives access to the “UTILITIES” menus, controlling hardcopy setups, GPIB addresses and special modes of operation. Chapter 12.
The WAVEFORM STORE button “STORE W’FORM” menus, used for storing waveforms to internal or external memory. Chapter 13.
Whereas, WAVEFORM RECALL “RECALL W’FORM”: menus for retrieving waveforms stored in internal or external memory. Chapter 13.
CURSORS/MEASURE menus, used for making precise cursor measurements on traces, and “MEASURE”, for precise parameter measurements. Chapter
14.
4–6
offers up the “CURSORS” Setup
accesses the
calls up
And PANEL SETUPS gives access to the “PANEL SETUPS” menus for saving and recalling a configuration of the instrument.
See Chapter 13.
SCREEN DUMP — prints or plots the screen display to an on-line hardcopy device,
via the GPIB, RS-232-C or Centronics interface ports, or directly to an external thermal graphics printer. Hardcopies can also be generated as data files onto floppy, memory card or portable hard disk.
Once SCREEN DUMP is pressed, all displayed information will be copied. However, it is possible to copy the waveforms without the grid by turning the grid intensity to 0 with the “Display Setup” menu.
While a screen dump is taking place — indicated by the on-screen “PRINTING” or “PLOTTING” message — it can be aborted by pressing SCREEN DUMP a second time. It will take a certain amount of time for the buffer to empty before copying stops.
CLEAR SWEEPS — restarts operations requiring several acquisitions, or sweeps,
including averaging, extrema, persistence and pass/fail testing, by resetting the sweep counter(s) to zero.
SHOW STATUS — menu entry to “STATUS”, which shows summaries of the
instrument’s status for acquisition, system and other aspects. See
Chapter 16.
4–7
Screen Topography
Introduction to the
Controls
The sections of the screen shown here and described below, which surround the grid, contain a variety of useful information as well as accessing specific commands and functions.
4–8
Real-Time Clock field: powered by a battery-backed real-time clock, it displays the current date and time.
Displayed Trace Label indicates each channel or channel displayed, the time/div and volts/div settings, and cursor readings where appropriate. It indicates the acquisition parameters set when the trace was captured or processed, while the Acquisition Summary field (below) indicates the present setting.
Acquisition Summary field: timebase, volts/div, probe attenuation and coupling for each channel, with the selected channel highlighted. It indicates the present setting, while the acquisition parameters set when the trace was captured or processed are indicated in the Displayed Trace label (above).
Trigger Level arrows on both sides of the grid that mark the trigger voltage level relative to ground level.
Trigger Delay: an arrow indicating the trigger time relative to the trace. The delay can be adjusted from zero to ten grid divisions (pre-trigger), or zero to 10 000 (post-trigger) off­screen. Pre-trigger delay appears as the upward-pointing arrow, while post-trigger is given as a delay in seconds.
Trigger Status field shows sample rate and trigger re-arming status (AUTO, NORMAL, SINGLE, STOPPED). The small square icon flashes to indicate that an acquisition has been made.
Trigger Configuration field: icon indicating type of trigger, and information on the trigger’s source, slope, level and coupling, and other information when appropriate.
Trace and Ground Level: trace number and ground-level marker.
4–9
Introduction to the
AUTO
SETUP
Controls
Other Fields
(not illustrated here)
Time and Frequency field: displays time and frequency relative to cursors beneath the grid. For example, when the absolute time cursor (the cross-hair) is activated by selection from the “MEASURE” menu group, this field displays the time between the cursor and the trigger point.
Message field: used to display a variety of messages, above the grid, including warnings, indications and titles showing the instrument’s current status.
General Instrument Reset: Simultaneously press the AUTO SETUP button, the top menu button, and the RETURN button. The scope will revert to its default power-up settings.
Press:
!
+ +
4–10
5
Channel Controls
These enable selection of displayed traces and adjustment of vertical sensitivity and offset.
TRACE ON/OFF Pressing these buttons either
displays or switches off the corresponding channel trace. When a channel is switched on, the OFFSET and VOLTS/DIV controls will then be attributed to this, the active channel. On two­channel models (right), each channel has its own set of unique, dedicated controls.
CHANNELS, Coupling & Probes
SELECT CHANNEL On four-channel models
(right), these buttons are used to attribute all the vertical controls to one channel, independent of whether or not it is the channel displayed. The selected channel number is highlighted in the Acquisition Summary field (see previous chapter).
OFFSET — vertically positions the
active channel.
5–1
CHANNELS, Coupling & Probes
FIND — automatically adjusts offset and volts/div to match the active
channel’s input signal.
VOLTS/DIV — selects the vertical sensitivity factor either in a 1–2–5 sequence
or continuously (see VAR, below ). The effect of gain changes on the acquisition offset can be chosen from the “SPECIAL MODES” menu.
VAR — allows the user to determine whether the VOLTS/DIV knob will
modify the vertical sensitivity in a continuous manner or in discrete 1–2–5 steps.
The format of the vertical sensitivity in the Acquisition Summary field (bottom left of screen) shows whether the VOLTS/DIV knob is operating in continuous or stepping mode.
COUPLING — menu-entry button that accesses the “Coupling” menus (see next
section).
5–2
Coupling
Coupling Menus Press for access to selection of:
Ø Coupling and grounding of each input channel Ø ECL or TTL gain, offset and coupling preset for the
channel shown
Ø Bandwidth limiter for all channels Ø Probe attenuation of each input channel.
Coupling
Used to select the input channel’s coupling. If an overload is detected, the instrument will automatically set the channel to the grounded state: the menu can then be reset to the desired coupling.
V/div Offset
When NORMAL is highlighted, pressing the corresponding menu button sets the offset, Volts/div, and input coupling to display ECL signals. Press the button a second time and the settings for TTL signals are given. And a third time returns the settings to those used at the last manual setup of the channel.
Global BWL
To turn the bandwidth limit “OFF” or “ON”. The bandwidth can be reduced from 500 MHz or 1 GHz, to either 200 MHz or 25 MHz, or 30 MHz (–3dB), depending on the model (see Appendix A). Bandwidth limiting can be useful in reducing signal and system noise or preventing high-frequency aliasing, reducing — for example — any high-frequency signals that may cause aliasing in single-shot applications.
Note: This command is global and affects all input channels.
Probe Atten
Sets the probe attenuation factor related to the input channel (see following for probe details).
5–3
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