Bio & Station Info - ProbeScope V4.1 for Windows/DOSCat. No. 22-310 OWNER’S MANUAL Please read before using this equipment. ProbeScope V4.1 for Windows/DOS 22-310.fm Page 1 Friday,

Cat. No. 22-310

OWNER’S MANUAL

Please read before using this equipment.

ProbeScope V4.1for Windows/DOS

22-310.fm Page 1 Friday, August 6, 1999 12:26 PM

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FCC INFORMATION

Modifying or tampering with your Radio Shack Probe-Scope’s internal components can cause a malfunctionand might invalidate your ProbeScope’s warranty andvoid your FCC authorization to operate it. If your Probe-Scope is not performing as it should, take it to your lo-cal Radio Shack store for assistance.

This device complies with Part 15 of the FCC Rules.Operation is subject to the following two conditions: (1)This device may not cause harmful interference, and(2) this device must accept any interference received,including interference that may cause undesired oper-ation.

This device complies with the limits for a Class B digitaldevice, as specified in Part 15 of FCC Rules. Theselimits provide reasonable protection against radio andTV interference in a residential area. However, yourProbeScope might cause TV or radio interference evenwhen it is operating properly. To eliminate interference,you can try one or more of the following:

• Reorient or relocate the TV or radio’s antenna.

• Increase the distance between the equipment andthe TV or radio.

• When using an AC adapter, use outlets on differ-ent electrical circuits for this device and the TV orradio.

If the problem persists, consult your local Radio Shackstore for assistance.

© 1996 Tandy Corporation.All Rights Reserved.

Microsoft Windows and MS-DOS are registered trademarks of Microsoft Corporation.

Radio Shack is a trademark used by Tandy Corporation.


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SAFETY INSTRUCTIONSWarning: Use extreme caution in the use of this de-vice. Improper use of this device can result in injury ordeath. Follow all the safeguards suggested in this own-er’s manual in addition to normal safety precautions indealing with electrical circuits. Do not use this device ifyou are unfamiliar with electrical circuits and testingprocedures.

Not for commercial or industrial use .

This oscilloscope is designed to ensure the safest op-eration possible. However, safe operation depends onyou, the operator. Make sure you follow these simplesafety rules:

• Read all of these instructions carefully, and savethem for your reference.

• Follow all warnings and instructions marked onthe ProbeScope.

• When making voltage measurements, nevertouch the ProbeScope’s tip or a hot wire in ACwiring circuits. If you do, you could receive anelectric shock.

• Never apply the ProbeScope to a source of powergreater than 100V DC/AC peak-to-peak. Doing socould cause electrical shock or damage to theProbeScope.

Caution : If you do not know the level of the volt-age to measure in manual range control, alwaysstart at the highest range: 100V DC or AC.

• Never try to measure any voltage more than 30VAC on a DC source bias. Doing so might dam-age your ProbeScope.


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• Always discharge filter capacitors in the circuitunder test before you attach the ProbeScope. Ifthe ProbeScope touches an undischarged capac-itor, it could damage it. If you touch an undis-charged capacitor, you could receive an electricshock.

• Always turn off power and disconnect the Probe-Scope before you change power sources.

• Because many AC-DC sets have a potentially hotchassis, be sure the top of your workbench andthe floor underneath it are made of nonconductivematerials.

• Unplug the ProbeScope before cleaning it. Do notuse liquid or aerosol cleaners. Use a damp clothfor cleaning and then wipe it dry immediately.

• Do not use the ProbeScope near water (for exam-ple, a bathtub, washbowl, kitchen sink, laundrytub, wet basement, or swimming pool).

• Do not use unapproved attachments.

• The ProbeScope should be operated from a 9-13V DC power source, such as a battery or DCpower supply.

• Do not allow anything to rest on the power cord.Do not locate the power supply where peoplemight walk on the cord.

• If your ProbeScope doesn’t operate normally, inparticular if any unusual sounds or smells comefrom it, immediately unplug it and contact yourlocal Radio Shack store.

• Do not attempt to service the ProbeScope your-self; opening or removing the cover can exposeyou to dangerous voltage or other hazards.


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• Unplug the ProbeScope from the DC powersource and refer servicing to qualified service per-sonnel under the following conditions:

— If the power cord is damaged or frayed

— If the ProbeScope has been exposed to rain orwater

— If the ProbeScope does not operate normallyand you are following the operating instruc-tions

— If the ProbeScope has been dropped or dam-aged

— If the ProbeScope exhibits a distinct change inperformance

• This Radio Shack ProbeScope is fully calibratedand tested. Under normal use, no further internaladjustment should be necessary. Adjust onlythose controls covered by the operating instruc-tions. Improper adjustment of other controls mightresult in damage and might require extensivework by a qualified technician to restore theProbeScope to normal operation. If the Probe-Scope should require repair, do not try to repair ityourself. Take it to your local Radio Shack store.


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FEATURES

Your Radio Shack ProbeScope V4.1 for Windows/DOSis a microprocessor-controlled oscilloscope and digitalvoltmeter housed in a small probe with a backlit miniLiquid Crystal Display (LCD). All oscilloscope parame-ters are menu-driven and selected by pressing one oftwo push buttons. You can quickly and single-handedlyset all parameters while looking at the point of mea-surement, the probe’s controls, and the display. Thiseliminates the need for any head movement, makingthe ProbeScope the easiest-to-use measurement toolavailable.

The ProbeScope includes these features:

Ten Selectable Sampling Rates — lets you displaysignals in a wide variety of waveforms, from a smallfraction of a waveform to multiple waveforms of themeasured signal.

Multiple Trigger Sources — lets you select whetherthe oscilloscope starts a measurement using an inter-nal or an external trigger.

Six Selectable Trigger Levels — lets you select bothrising and falling signal events at different levels.

Selectable Input Voltage Ranges — lets you selectthe range of the measured signal for the most accuratereadings.

Selectable Input Coupling — lets you select whetherthe signal to be measured is DC or AC coupled to thescope, and provides a zero reference for zero adjust-ment.

Signal Ground Line — lets you easily reference the in-coming signal.


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Trigger Jack — lets you connect an external triggersource.

Multiple Input Power Sources — lets you connect9VDC–13VDC external power from a battery using thesupplied power cable with alligator clips, or an optionalAC adapter.

Liquid Crystal Display (LCD) — displays the record-ed signal.

Software Interface — lets you use your computer todisplay and record measurements.

• To use this ProbeScope’s software with MicrosoftWindows®, the computer must have at least:

— 80386 CPU

— 400K of available hard disk storage space

— Windows 3.1 or later

• To use this ProbeScope’s software with MS-DOS®, the computer must have at least:

— 800K of available hard disk storage space

— DOS Version 3.3 or later


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CONTENTS

Preparation ............................................................. 9Installing the MS-Windows Software ................ 9Installing the MS-DOS Software ..................... 10Connecting Power .......................................... 10

Using a Bench-Top Power Supply ......... 11Using an AC Adapter ............................. 12

Connecting a Computer .................................. 13Connecting the External Inputs ....................... 14

Basic Operation ................................................... 15Using the Software ......................................... 15Using the Tool Bar .......................................... 16Using the Available Modes ............................. 18

Selecting a Mode ................................... 18Mode Definitions .................................... 19

Using the Oscilloscope ....................................... 22Establishing the Screen’s

Vertical Deflection Factor ....................... 22Measuring a DC Voltage ................................. 24Measuring the DC Bias Voltage

of an AC Signal ...................................... 28Measuring an AC Voltage ............................... 30Measuring an Instantaneous Voltage ............. 33Frequency Measurements .............................. 36Phase Measurements ..................................... 40

Grid Overlay Degree Calculation ........... 40Measuring Phase ................................... 41Single Sweep Waveform Measurements 44

Using the DVM ...................................................... 48

Care and Maintenance ......................................... 51

Specifications ........................................................ 52


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PREPARATION

Use this manual as a guide to prepare and use theProbeScope using either the ProbeScope’s LCD or acomputer monitor.

The computer’s software offers additional help screensthat can guide you through the many ProbeScope func-tions, modes, and available options.

INSTALLING THE MS-WINDOWS SOFTWARE

1. Start Microsoft Windows.

2. Insert the supplied disk into your computer’s A:drive.

3. Click File in the Program Manager window.

4. Click Run ... in the File Menu.

5. Type a:\setup in the Command Line box in theRun window, then click .

6. Click in the Setup window to define thedirectory where you want the software installed.C:\PROSCOPE (the suggested path) appears inthe Path box.

7. Click to install the ProbeScope soft-ware in the suggested directory, or...

Enter the desired directory name, then click.

OK

Continue

Continue

Continue


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INSTALLING THE MS-DOS SOFTWARE

If your computer does not have MS-Windows, you caninstall the supplied MS-DOS software into your com-puter’s C: drive.

1. Type md c:\proscope to create a directory onyour computer’s C: drive where you can install theProbeScope software.

2. Insert the supplied disk in your computer’s A:drive.

3. Type copy a:*.* c:\proscope to copy all thefiles from your A: drive to the C:\proscope direc-tory.

CONNECTING POWER

You can power the ProbeScope from:

• A bench-top power supply (such as Cat. No. 22-120)

• A 9-volt battery (such as Cat. No. 23-553)

• An AC adapter (such as Cat. No. 273-1651)


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Using a Bench-Top Power Supply

If you are using a bench-top power supply or a 9-voltbattery:

1. Set the input coupling switch to GND.

Important : You must first set the input couplingswitch to GND to initialize the probe every timeyou turn on the ProbeScope, even if you want tomeasure a circuit’s signal using the same settingspreviously used.

2. Insert the supplied power cable’s barrel plug intothe Probe-Scope’s power jack.

3. Connect the supplied power cable’s alligator clipsto the DC power source.

Cautions:

• Make sure the input power source is between+9V DC and +13V DC.

• Make sure to observe the proper polarity byconnecting the red clip to + and the black clipto –.


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Using an AC Adapter

If you are using an optional AC adapter:


Important : You must first set the input couplingswitch to GND to initialize the probe every timeyou turn on the ProbeScope, even if you want tomeasure a circuit’s signal using the same settingspreviously used.

2. Insert the proper-sized barrel plug into theadapter’s wire jack so it reads TIP +.

3. Insert the barrel plug into the ProbeScope’spower jack.

4. Connect the AC adapter’s power module to astandard AC outlet.

Caution : Use only an AC adapter that supplies 9–13 volts DC, delivers at least 100 milliamps, andhas a barrel plug that correctly fits the Probe-Scope’s power jack with its center tip set to posi-tive. The recommended AC adapter meets thesespecifications. Using an adapter that does notmeet these specifications could damage theProbeScope or the adapter.

AC OutletStandard


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CONNECTING A COMPUTER

1. Plug the supplied serial cable’s 9-pin female con-nector into your computer’s 9-pin male serial portconnector.

Note : If your computer has a 25-pin serial portconnector, you can use a 9-pin to 25-pin adaptercable.

2. Insert the supplied serial cable’s barrel plug intothe ProbeScope’s serial connector.

9-Pin MaleSerial Port

Serial Cable’s 9-PinFemale Connector

To the Barrel plug

Serial Cable’sBarrel Plug

To thePower Source

To the 9-PinFemaleConnector


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CONNECTING THE EXTERNAL INPUTS

1. Connect the supplied white signal wire’s plug intothe GROUND (0 Volt) jack.

2. If you are using an external trigger source, con-nect the supplied gray trigger wire’s plug into theEXT. TRIGGER jack.

Caution : If you are not going to use an externaltrigger source, do not connect the gray triggerwire to the ProbeScope.

Ground (0 Volt)Ext.Trigger

Gray Wire White Wire

To the 9-PinFemale Connector

To the Power Source


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BASIC OPERATION

USING THE SOFTWARE

If all you want to do is make a quick and basic signaldetection or AC/DC voltage measurement, you cansimply use the ProbeScope’s display.

But, if you want to make a more detailed determinationof a measured signal (such as a frequency, signal am-plitude, phase shifting, DC biasing, etc.), you need touse the ProbeScope’s software to display the mea-surements on your computer’s monitor.

To use the ProbeScope with your computer:

• If you are using MS-Windows:

a.Double click the Radio Shack ProbeScope Pro-gram Group.

b.Then double click theRadio Shack Probe-Sope icon.

• If you are using MS-DOS:

a.Type cd c:\proscope then press toenter the ProbeScope directory.

b.Type scopedos.exe to select the Probe-Scopesoftware.

c.Press to start the ProbeScope soft-ware.

Note : The operating instructions in this owner’s manu-al are specific to using MS-Windows.

WTT

V3.0V4.1

Enter

Enter


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USING THE TOOL BAR

After you start the ProbeScope V4.1 for Windows/DOSsoftware, these icons appear on your monitor’s display.(You can also access these functions using the provid-ed keyboard shortcuts.)

Opens an existing ProbeScope document(Ctrl-O)

Saves the active document (Ctrl-S)

Enters comments about the current Probe-Scope document (Ctrl-C)

Shows and hides the oscilloscope screen’sgrid (Ctrl-G)

Shows and hides the vertical cursors(Ctrl-V)

Shows and hides the horizontal cursors(Ctrl-H)

Shows and hides the trigger level line(Ctrl-L)

Note : You can select this mode only whenthe Trigger mode is set to ± INTERN or ±EXTERN.

TEXT TLHOLD

SECHz ? ?

H0.12

HOLD

TEXT

TL


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Freezes the measured signal on the oscillo-scope display (Ctrl-l)

Switches between seconds and Hertz forthe measured signal (Ctrl-U)

Note : You can use this mode only when thevertical cursors appear on the oscilloscopedisplay.

Calls up the print dialog menu (Ctrl-P)

Turns on and off the Digital Voltmeter(DVM) function (Ctrl-D)

Freezes the displayed DVM measured val-ue (Ctrl-A)

Note : You can use this mode only when theDVM function is selected.

Provides information about ProbeScope

Opens the help files (Shift+F1)

HOLD

HzSEC

HOLD0.12 H

?

?


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USING THE AVAILABLE MODES

Selecting a Mode

1. Press the Menu button to display the availablemodes shown below.

2. Press the Select button to set the desired optionin each of the available modes.

Mode Options

Timebase Time Grid Set Grid Not set

50 ns100 ns0.5 ms

1 ms5 ms

10 ms50 ms0.1 ms0.5 ms

1 ms

0.5 ms/div1 ms/div5 ms/div10 ms/div50 ms/div100 ms/

div0.5 ms/div1 ms/div5 ms/div10 ms/div

20 MSa/s10 MSa/s2MSa/s1 MSa/s200 kSa/s100 kSa/s20 kSa/s10 kSa/s2 kSa/s1 kSa/s

50 ns100 ns0.5 ms1 ms5 ms10 ms50 ms0.1 ms0.5 ms1 ms

20 MSa/s10 MSa/s2 MSa/s1 MSa/s200 kSa/s100 kSa/s20 kSa/s10 kSa/s2 kSa/s1 kSa/s

TriggerSource

AUTO+ INTERN– INTERN

+ EXTERN– EXTERN

Backlight

SerialLine

VoltageSelector

AC/DCGND Menu

Select

PowerJack

ZeroLevel Adjust

Probe

LCD

ON OFF


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Mode Definitions

Timebase — The ProbeScope’s timebase is its sam-pling rate (the rate at which measurements are taken)and is not always the same as used in typical oscillo-scopes.

• The timebase on the ProbeScope’s LCD repre-sents the probe’s sampling rate and is shown inseconds (such as 0.1 ms, meaning that theProbeScope takes a measurement every 0.1 ms).

• The timebase on the computer’s display dependson whether or not you select the grid overlay toappear on the oscilloscope’s display.

– When the grid is not displayed, the timebaseon the computer’s display shows the Probe-Scope’s sampling rate (matches the timebaseshown on the ProbeScope’s LCD).

– When the grid is shown, the timebase on thecomputer’s display is 10 times the LCD’s sam-pling rate and is shown in seconds per grid di-vision (the same as in typical oscilloscopes).

Function

Trigger Level

± INTERN ± EXTERN

± 0.1V± 0.3V± 0.5V

± 1V± 3V± 5V

± 10V± 30V± 50V

Trigger Mode

Mode Options

SCOPE DVM

SINGLE RUN

± 0.1V± 0.3V± 0.5V


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Trigger Source — A trigger source selection deter-mines how a received pulse or signal is to be monitoredor measured. The five selectable trigger sources are:

AUTO: The ProbeScope continuously measuresand records signals each time a trigger occurs re-gardless of its level (higher, lower, or equal to theincoming signal). If you set the input couplingswitch to GND, the ProbeScope automatically setsthe trigger to AUTO.

+ INTERN: The ProbeScope records signals onlywhen the defined trigger event occurs. The signalis recorded when the trigger level is equal to the in-coming signal and the signal is rising.

– INTERN: The ProbeScope records signals onlywhen the defined trigger event occurs. The signalis recorded when the trigger level is equal to the in-coming signal and the signal is falling.

Note: The maximum and minimum voltage levelsof the + or – internal trigger depends on the InputVolta ge Selector

+ EXTERN: The ProbeScope records signals onlywhen the defined trigger event occurs. The signalis recorded when the trigger level is equal to thesignal present at the external trigger plug and thesignal is rising.

– EXTERN: The ProbeScope records signals onlywhen the defined trigger event occurs. The signalis recorded when the trigger level is equal to thesignal present at the external trigger plug and thesignal is falling.

00.10.30.5

-0.1-0.3-0.5

0135

-1-3-5

0103050

-10-30-50

1 V 10 V 100 V


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Note: The maximum and minimum voltage levelsof the + or – external trigger is always ±0.5 V

Trigger Mode — The trigger mode determines when anew measurement is to be taken and displayed. Theseare the two available trigger modes:

RUN: The probe records a new signal every timethe defined trigger event occurs. Use this mode tomeasure or monitor a continuously running signal.

SINGLE: The probe records a new signal eachtime you press the Select button and the definedtrigger event occurs. Use this mode to measure ormonitor a signal that occurs only once, such as thenoise heard when you turn on an electronic device.

Backlight — Lights the LCD so you can use it in lowlight areas.

Function — Lets you use the ProbeScope either as anoscilloscope or a digital voltmeter.

Trigger Level — Establishes the voltage level at whichthe measurement will begin.

00.10.3

0.5

-0.1-0.3-0.5


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USING THE OSCILLOSCOPE

The following applications describe how to make basicwaveform measurements with the ProbeScope. Theseapplications are not described in detail, but are de-signed to familiarize you with basic oscilloscope oper-ating techniques.

Cautions :

• Never try to measure an AC peak-to-peak or a DCvoltage that exceeds 100 volts.

• If you are not sure of what the measured signallevel is, always start with the highest range.

ESTABLISHING THE SCREEN’S VERTICAL DEFLECTION FACTOR

When a measured signal appears on the oscilloscope’sscreen, you can use the grid overlay to measure thevertical displacement, then multiply this displacementby the deflection factor of the oscilloscope’s screen toestimate the measured voltage.

To do this, you must first establish the screen’s verticaldeflection factor.

1. Click on the grid icon so thescreen’s grid overlay appears.


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2. Divide the input voltage selector setting (1, 10, or100) by 4 (the number of vertical squares).

The result is the screen’s vertical deflection factor.For example, if the input voltage selector is set to10, and you divide 10 by 4, then the screen’s ver-tical deflection factor is 2.5 volts/square

Therefore, if a measured signal is about 3squares high, then the signal is estimated to beabout 7.5 volts (3 ¥ 2.5 = 7.5).

Notes :

• The screen’s deflection factor applies only to theoscilloscope screen on the computer’s monitor,and does not apply to the display on the Probe-Scope.

• The grid overlay is not necessary if you want onlyto detect a signal but do not need to calculatevoltage or frequency.

• The grid is necessary in order to calculate volt-age, frequency, or both without using the cursors.

Monitor’s DisplayProbeScope’s Display

Vertical Deflection


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MEASURING A DC VOLTAGE

In oscilloscope measurements, the DC component of awaveform is usually measured in terms of its DC flat-line or AC average displacement above or below a ref-erence line.

The maximum DC voltage measurement you can makeis determined by the positions of the input voltage se-lector and the zero line.

For example, if the input voltage selector is set to 10and the zero line is set at the middle position, the max-imum measurement is ±5 Volts.

Follow these steps to measure a DC voltage deflection.

1. Continuously press the ProbeScope’s Menu but-ton until DVM appears on its display, then pressthe Select button.


Note : When you set the input coupling switch toGND, the ProbeScope automatically resets thetrigger mode to AUTO.

3. Connect the GROUND (0 volt) wire to the signalsource’s ground or reference level.

0

–5V

+5V

Zero Line


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4. Rotate Zero Level to position the zero referenceline:

a.On the bottom of the computer display until the indicator appears on the screen to get the

maximum positive (+) measurement, or

On the top of the computer display until the in-dicator appears on the screen to get the maxi-mum negative (–) measurement.

b.Slowly re-adjust Zero Level in the oppositedirection until just past the point where the or

indicator disappears from the oscilloscopescreen on the computer’s display.

Notes :

• The grid must be turned on)

• The reference line on the oscilloscope displayshould be set to just above the bottom line orjust below the top line on the grid.

• The position on the grid overlay depends onthe input signal’s polarity and amplitude, butshould be chosen so the trace lies along one ofthe grid overlay’s major divisions. If the trace iswidened by stray interference, ground theprobe body near the point being measured.The trace position is the voltage reference lineand all voltage measurements are read inrespect to this line. (Do not adjust the verticalpositioning control after the reference is estab-lished.)

5. Set INPUT COUPLING to DC.

6. If it was necessary to ground the tip (see Step 3note), remove the tip from the ground or referencevoltage. This readies the tip so you can use it tomake a measurement.


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7. Set the input coupling switch to DC. The selectedsetting appears on your computer’s monitor.

8. If you know the level of the signal to be measured,set the input voltage switch as follows.

Note: If you do not know the level of the signal tobe measured, always set the input voltage switchto 100V.

9. Click on the horizontal cursor iconto display the horizontal cursors.The Volt : box appears belowthe grid display.

a.Place the mouse cursor directly over the oscillo-scope screen’s lower horizontal cursor until thecursor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse up or down until the screen’slower horizontal cursor is superimposed directlyon the reference line.

10. Apply the probe tip to the signal source. The oscil-loscope grid display vertically displaces the DCsignal’s flat-line away from the zero referenceline.

11. Click on the oscilloscope hold icon.

Switch Position Measures

1V10V

100V

0.00 – 1.00 V0.0 – 10.0 V

0 – 100 V

—

HOLD


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12. Calculate the DC signal using the oscilloscope’sgrid display as follows:

a.Place the mouse cursor directly over the oscillo-scope screen’s upper horizontal cursor until thecursor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse up or down until the screen’supper horizontal cursor is superimposed directlyon the DC signal’s flat-line waveform.

13. Click on the voltmeter icon. TheDVM: box at the bottom of the com-puter’s display shows the actualDC signal level.

Zero Reference Line

MAX

1V10V

or100V

DC flat-line waveform

7.5 V DC

DVM:


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MEASURING THE DC BIAS VOLTAGE OF AN AC SIGNAL

If you are measuring the DC component of an AC sig-nal (AC on a DC bias), calculate the waveform’s aver-age vertical distance from the zero reference line asfollows:

Note : The average level of a pure sinusoidal, square,or triangular waveform is the midpoint between thepositive and negative signal peaks.

1. Repeat Steps 1–9 of “Measuring a DC Voltage”on Page 24.

2. Apply the probe tip to the signal source. The oscil-loscope grid display vertically displaces the signalaway from the zero reference line.

3. Click on the oscilloscope hold icon.

4. Calculate the DC bias using theoscilloscope’s grid display as fol-lows:

a.Place the mouse cursor directly over the oscillo-scope screen’s upper horizontal cursor until thecursor’s shape changes to a cross.

Midpoint

HOLD


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b.While you press and hold the left mouse button,move the mouse up or down until the screen’supper horizontal cursor is superimposed directlyon the AC signal’s midpoint between the posi-tive and negative signal peaks.

Important : The DVM displaydoes not accurately measure ACon a DC bias. When making thistype of measurement, either turnoff the DVM display by clickingon the voltmeter icon or disre-gard its indication.

DC Signal Level

Zero Reference Line


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MEASURING AN AC VOLTAGE

In oscilloscope measurements, the AC component of awaveform is usually measured in terms of its peak-to-peak value. You can easily make this type of measure-ment by using the grid overlay on the oscilloscopescreen to measure the vertical distance between peaksand multiplying this distance by the oscilloscopescreen’s deflection factor. The result is the actual peak-to-peak voltage.

Follow these steps to measure a waveform’s peak-to-peak AC component.

Caution : To avoid an overload when measuring AC,make sure the zero line is centered vertically on thegrid overlay.


Note : When you set the input coupling switch toGND, the ProbeScope automatically resets thetrigger mode to AUTO.


3. Rotate Zero Level until the zero reference line iscentered vertically on the grid overlay.

Note : If the trace is widened by stray interference,ground the probe body near the point being mea-sured. The trace position is the voltage referenceline and all voltage measurements are read inrespect to this line. (Do not adjust the verticalpositioning control after the reference is estab-lished.)


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5. Set the input coupling switch to AC.

6. If you know the level of the signal to be measured,set the input voltage switch as follows.

Note: If you do not know the level of the signal tobe measured, always set the input voltage switchto 100V.


a.Place the mouse cursor directly over the oscillo-scope screen’s upper horizontal cursor. Thecursor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse up or down until the screen’supper horizontal cursor touches the top of thesignal peaks.

8. Apply the probe tip to the signalsource, then click on the oscillo-scope hold icon.

9. Measure the vertical distance between the posi-tive and negative peaks as follows:

Switch Position Measures

1V10V

100V

0.00 – 1.00 V0.0 – 10.0 V

0 – 100 V

—

HOLD


32

a.Place the mouse cursor directly over the oscillo-scope screen’s lower horizontal cursor. The cur-sor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse up or down until the screen’slower horizontal cursor touches the bottom ofthe signal peaks.

10. Click on the voltmeter icon. The DVM:box at the bottom of the computer’sdisplay shows the actual AC signallevel.

Notes :

• You can also calculate the approximate volt-age level by multiplying the approximate dis-tance by the deflection factor.

• This technique can also be used to makemeasurements between two other points onthe waveform.

• To accurately measure an AC peak-to-peakvoltage, you should have at least two com-plete cycles of a waveform on the display.

Vp-p

Zero Reference Line

3.1V AC

DVM:


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MEASURING AN INSTANTANEOUS VOLTAGE

You can use the ProbeScope to measure an AC sig-nal’s instantaneous voltage at any given point on thesignal waveform.



3. Rotate the Zero Level to vertically position thetrace to a convenient line on the grid overlay.

Note : The position on the grid overlay dependson the polarity and amplitude of the input signal,but should be chosen so the trace lies along oneof the major divisions on the grid overlay. If thetrace is widened by stray interference, ground theprobe body near the point being measured. Thetrace position is the voltage reference line and allvoltage measurements are read in respect to thisline. (Do not adjust the vertical positioning controlafter the reference is established.)


5. Set the input coupling switch to DC.


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a.Place the mouse cursor directly over the oscillo-scope screen’s lower horizontal cursor. The cur-sor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse up or down until the screen’slower horizontal cursor touches the referenceline.


8. Measure the vertical distance between a desiredpoint on the waveform and the reference line asfollows:

a.Place the mouse cursor directly over the oscillo-scope screen’s upper horizontal cursor. Thecursor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse up or down until you place thescreen’s upper horizontal cursor on the desiredpoint on the waveform.

—

HOLD

Zero Reference Line


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Note: If you place the screen’s upper horizontalcursor anywhere along the waveform, the mea-surement equals the instantaneous voltage.

The Volt : box shows the instantaneousvoltage level of the signal at the measuredpoint.

Note : You can also calculate the approximatevoltage levels by multiplying the approximatedistance by the deflection factor.

—

Volt :—

8.7 V


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FREQUENCY MEASUREMENTS

Since frequency and time are reciprocals of each other,when you know one (frequency or time), you can easilysolve for the other (f= , then t= ). Therefore, if youmeasure the time period of a recurrent waveform as 0.2ms, the frequency is 5 MHz (or ).

Note : Since a DC voltage does not have a frequency,you cannot make frequency measurements on a DCvoltage.



3. Rotate the Zero Level to vertically center the traceon the grid overlay.




6. Click on the vertical cursor icon todisplay the vertical cursors. The

Time : box appears below thegrid display.

1t

1f

10.2 ms

—


37

a.Place the mouse cursor directly over the oscillo-scope screen’s left vertical cursor. The cursor’sshape changes to a cross.

b.While you press and hold the left mouse button,move the mouse left or right until the screen’sleft vertical cursor touches a point where the ris-ing or falling edge of the waveform intersectswith the zero reference line.


8. Measure the horizontal distance between rising orfalling points on the displayed waveform as fol-lows:

a.Place the mouse cursor directly over the oscillo-scope screen’s right vertical cursor. The cur-sor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse left or right until the screen’sright vertical cursor touches the next pointwhere the waveform’s rising or falling edgeintersects with the zero reference line.

Note : To avoid inaccurate frequency measure-ments, make sure you set the cursors in Steps6b and 8b to two consecutive rising or two con-secutive falling points of a displayed waveform.

HOLD


38

The frequency measurement will be inaccurateif you set one vertical cursor to a rising edgeand the other to a falling edge.

c.When you select HERTZ, the value rep-resents the signal’s frequency. When you selectSeconds , the value represents thetime between the cursors.

Notes :

• You can click the tool bar button to togglebetween Hertz or Seconds.

• The timebase on the computer’s Timebasedisplay changes with the grid overlay settings.

One Cycle of the Waveform

Zero Reference Line

Time —

Time —0.10000 KHz 10.0 ms

Hertz or Seconds

Time — Time —

HzSEC


39

For example:

– If the grid is not shown, then the timebasedisplayed on the monitor is the same as theProbeScope’s set sampling rate.

Since f= , if the time period of a recurrentwaveform is measured as 1ms, the sam-pling frequency is 1000 samples per second(or ).

– If the grid is shown, then the displayed time-base is the timebase of the grid. This time-base is 10 times the normal sampling rate(because there are 10 samples within eachdivision of the grid).

– You can change the timebase by pressingthe Select button, without first pressing theMenu button.

• When measuring a waveform:

a.If the either the time or frequency is known,simply calculate the reciprocal of the knownvalue to figure the unknown value.

b.Start with the smallest selectable timebaseon the ProbeScope (50 ns) and increase itone step at a time (100 ns, 0.5 ms, 1 ms, 5ms, 10 ms, 50 ms, 0.1 ms, 0.5 ms, or 1 ms)until the displayed signal shows one or twocomplete cycles of a waveform.

1ms 1kSa/s

SamplingFrequency

SamplingRate

1t

11 ms

10ms/div 1kSa/s

SamplingFrequency

Timebase


40

Frequency Measuring Limits :

• You must have a minimum of one completecycle of a waveform on the display.

• You cannot have more than one cycle per divi-sion.

PHASE MEASUREMENTS

You can compare two signal waveforms of the samefrequency either from two separate points on the sameelectronic device, or from similar points on two sepa-rate electronic devices. The phase difference betweenthe two signal waveforms is measured in degrees.

Note : You must calculate the number of degrees perdivision for this measurement to work with your Probe-Scope.

Grid Overlay Degree Calculation

Since a complete cycle of a sine wave is 360 degrees,it is easy to calibrate the grid overlay in degrees. Forexample, if the ProbeScope’s controls are adjusted soone cycle of the input waveform spans 9 squares onthe grid, then each square represents 40 degrees ofthe complete cycle (360/9=40). The grid display is thenconsidered to be calibrated to 40 degrees per square.


41

Measuring Phase

Follow these steps to measure the phase differencebetween two signals.



3. Rotate Zero Level to vertically center the trace onthe grid overlay.

Note : If the trace is widened by stray interference,ground the probe body near the point being mea-sured.

The trace position is the voltage reference lineand all voltage measurements are read in respectto this line. (Do not adjust the vertical positioningcontrol after the reference is established.)



6. Click on the vertical cursor iconto display the vertical cursors.The Time : box appears belowthe grid display.

7. Apply the ProbeScope’s tip tothe first signal source, then clickon the oscilloscope hold icon.

8. Measure the slope of the first circuit as follows:


—

HOLD


42

b.While you press and hold the left mouse button,move the mouse left or right until the screen’sleft vertical cursor touches a point where the ris-ing or falling edge of the first waveform inter-sects with the zero reference line.

9. If the second signal source to be measured is aseparate circuit on the same electronic device,simply remove the ProbeScope’s tip from the firstcircuit’s signal source and apply it to the next cir-cuit’s signal source.

If the second signal source to be measured is aseparate electronic device:

a.Remove the alligator clip on the ground wireand the probe’s tip from the first signal source’sground and signal references.

b.Connect the alligator clip on the ground wire tothe second signal source’s ground reference.

c.Apply the ProbeScope’s tip to the second signalsource’s circuit to be measured.

10. Measure the slope of the second circuit as fol-lows:

a.Place the mouse cursor directly over the oscillo-scope screen’s right vertical cursor. The cur-sor’s shape changes to a cross.

b.While you press and hold the left mouse button,move the mouse left or right until the screen’sright vertical cursor touches a point where therising or falling edge of the second waveformintersects with the zero reference line.

11. Calculate the number of degrees per division (see“Grid Overlay Degree Calculation” on Page 40).


43

Note : To avoid inaccurate phase measurements,make sure you set the cursors in Steps 8b and10b to two corresponding rising or two corre-sponding falling points on the displayed wave-forms. The phase measurement will be inaccurateif you set one vertical cursor to a rising edge andthe other to a falling edge.

c.When you select HERTZ, the value rep-resents the signal’s frequency. When you selectSeconds , the value represents thetime between the cursors.

Notes :



Phase Difference

Zero Reference Line

Time —

Ti me —

0.10000 KHz 10.0 ms

Hertz or Seconds

Time — Time —

HzSEC


44

12. Divide the displacement between the vertical cur-sors (the value shown in the box) by thevalue in the timebase (time-per-division), thenmultiply the result by the number of degrees perdivision calculated in Step 11.

Note : The relative amplitude of the measured sig-nals does not affect the phase measurement if thesignals are centered around the grid’s center hori-zontal line.

Single Sweep Waveform Measurements

You can measure a waveform that occurs only oncewithout repeating, such as a noise spike that occurswhen you turn on an electronic device.

Follow these steps to measure a single sweep wave-form.

1. Continuously press the Menu button until the trig-ger mode appears on the display.



4. Rotate Zero Level to vertically position the trace toa convenient line on the grid overlay.

—Time

Zero Reference Line


45




7. Press the Select button to set the trigger mode to:

• + EXTERN (if you want to trigger on the incom-ing signal’s rising edge), or

• – EXTERN (if you want to trigger on the incom-ing signal’s falling edge).

8. Press the Menu button so TRIGGER LEVELappears on the ProbeScope’s display.

9. Continuously press the Select button until you setthe trigger level as desired.

Note : The trigger level you select sets the level ofthe incoming waveform that causes the Probe-Scope to begin reading the signal. The Probe-Scope shows the trigger level on the left side ofthe LCD.

10. Press the Menu button until the MODE screenappears on the ProbeScope’s display.

11. Press the Select button so SINGLE appears onthe ProbeScope’s display.

12. Press the Menu button so WAITING! appearson the ProbeScope’s display.


46

13. Apply the probe tip to the signal source to bemeasured.

14. Turn on the device to be measured. A singlewaveform appears on the oscilloscope screen.

15. Measure the single sweep frequency as follows:


b.While you press and hold the left mouse button,move the mouse left or right until the screen’sleft vertical cursor touches the point where therising edge of the waveform intersects the zeroreference line.

c.Place the computer’s mouse cursor directly overthe oscilloscope screen’s right vertical cursor.The cursor’s shape changes to a cross.

Left Cursor Right Cursor


47

d.While you press and hold the left mouse button,move the mouse left or right until the screen’sright vertical cursor touches the point where thenext rising edge of the waveform intersects thezero reference line.

e.When you select HERTZ, the valuerepresents the signal’s frequency. When youselect Seconds , the value representsthe time between the cursors.

Notes :



Time —

Time —

0.10000 KHz 10.0 ms

Hertz or Seconds

Time — Time —

HzSEC


48

USING THE DVM

The following applications describe how to make basicvoltage measurements using the ProbeScope’s digitalvoltmeter (DVM) mode. These applications are not de-scribed in detail, but are designed to familiarize youwith basic DVM operating techniques.

In digital voltmeter measurements, the measured ACor DC voltage is converted to digital values using ananalog-to-digital (A/D) converter.

In the AC mode, the ProbeScope rectifies the AC signalto convert it to DC. The DC is then converted to a digitalvalue by a 6-bit resolution A/D converter, then multi-plied by 0.707 to display the RMS value. You musthave at least two cycles of a waveform for the Probe-Scope to accurately measure AC DVM values.

Note : The voltmeter function is to be used only for pureAC and DC measurements. Only sine waves are al-lowed for AC measurements since the ProbeScopedoes not support true RMS functions. For measuringan AC signal on a DC bias, use the oscilloscope (see“Using the Oscilloscope” on Page 22).

In the DC mode, the DC is directly converted to a digitalvalue by the 6-bit resolution A/D converter. An averageof up to 128 recorded values appears on the screen. Anegative value is displayed when the average is belowthe reference line.

Follow these steps to measure a signal’s voltage level.

1. Continuously press the Menu button until theFUNCTION mode appears on the display.

2. Press the Select button to set the function modeto DVM, then press the Menu button again.


49



5. Rotate Zero Level to vertically position the trace toa convenient line on the grid overlay.

Caution : To avoid an overload when measuringAC, make sure the zero line is centered verticallyon the grid overlay.



7. Set the input coupling selector to AC or DC(depending on the voltage you want to measure).

8. Set the input voltage range to the appropriate 1V,10V, or 100V range scale.

Cautions :

• Always set the selector to the highest rangewhen you are not sure of the voltage to bemeasured.

• Never exceed 100 Volts AC (peak-to-peak) orDC between the measured test point andground.


50

• The maximum AC RMS measurement is (Volt-age Range Selection / 2) ¥ 0.707.

9. Click on the DVM icon on thetool bar to display the DVM box.

10. Apply the probe tip to the circuit to be tested. Theactual voltage appears on the ProbeScope’s dis-play and on the monitor’s DVM box.

If you want to freeze the current voltage readingso you can take another measurement reading forcomparison, click on the tool bar.

0.0 V AC

DVM:

3.6 V AC

DVM:

HOLD0.12 H


51

CARE AND MAINTENANCE

Your Radio Shack ProbeScope V4.1 for Windows/DOS is an example of superior design and craftsman-ship. The following suggestions will help you care forthe ProbeScope so you can enjoy it for years.

Keep the ProbeScope dry. If it gets wet,wipe it dry immediately. Liquids mightcontain minerals that can corrode theelectronic circuits.

Handle the ProbeScope gently andcarefully. Dropping it can damage circuitboards and cases and can cause theProbeScope to work improperly.

Use and store the ProbeScope only innormal temperature environments.Temperature extremes can shorten thelife of electronic devices and distort ormelt plastic parts.

Keep the ProbeScope away from dustand dirt, which can cause prematurewear of parts.

Wipe the ProbeScope with a damp clothoccasionally to keep it looking new. Donot use harsh chemicals, cleaning sol-vents, or strong detergents to clean theProbeScope.

Modifying or tampering with the ProbeScope’s internalcomponents can cause a malfunction and might invali-date your ProbeScope’s warranty and void your FCCauthorization to use it. If your ProbeScope is not per-forming as it should, take it to your local Radio Shackstore for assistance.

CLEANER


52

SPECIFICATIONS

Sampling Rates ......................................... 50, 100 ns.5, 1, 5, 10, 50 ms

.1, .5, 1 ms

DC Band Width ....................................... DC – 5 MHz

AC Band Width ................................ 100 Hz – 5 MHz

A/D Converter .................................... 6-Bit resolution

RAM ........................................................... 128 Bytes

Input Coupling .................. AC, DC, or GND (Ground)

Input Voltage Ranges ........................... 1V, 10V, 100V

Note : All voltages measurements are referenced to 0Vground. The effective ranges for AC volt measure-ments in DVM mode are 0.33V, 3.3V, and 33V sincethe peak-to-peak voltage must be digitized and con-verted to the RMS value.

Trigger Definitions .................. Auto, Internal, External

Trigger Levels ............................ Six selectable levels

Note : Level tolerances are dependent on the selectedinput voltage range: 1V ±.1V, 10V ±3V, 100V ±10V

Trigger Modes ......... Continuous RUN/SINGLE Cycle

Display ....... 16 ¥ 32 dots resolution, LED backlighted

Serial Line ............................................ 19.200 kBaud7 Data Bits, 1 Stop Bit, No Parity

DVM Accuracy ............................................ ±2 to ±5%(depending on the parameter settings)

Power Supply ............................................9 – 13V DCred (+) and black (–) alligator clips

Current Required ........ Backlight Off = 12 mA TypicalBacklight On = 85 mA Typical


53

Dimensions (HWD).......................... 61/2 ¥ 15/16 ¥ 3/4 in(165 ¥ 33 ¥ 19 mm)

Weight .............................. About 1 lb, 14.4 oz. (86 g)

Specifications are typical; individual units might vary.Specifications are subject to change and improvementwithout notice.


54

NOTES


55


RADIO SHACKA Division of Tandy Corporation

Fort Worth, Texas 76102

5A6 Printed in the USA

RADIO SHACK LIMITED WARRANTY

This product is warranted against defects for 90 days fromdate of purchase from Radio Shack company-ownedstores and authorized Radio Shack franchisees and deal-ers. Within this period, we will repair it without charge forparts and labor. Simply bring your Radio Shack salesslip as proof of purchase date to any Radio Shack store.Warranty does not cover transportation costs. Nor does itcover a product subjected to misuse or accidental damage. EXCEPT AS PROVIDED HEREIN, RADIO SHACKMAKES NO EXPRESS WARRANTIES AND ANYIMPLIED WARRANTIES ARE LIMITED IN DURATION TOTHE DURATION OF THE WRITTEN LIMITED WARRAN-TIES CONTAINED HEREIN. Some states do not permitlimitation or exclusion of implied warranties; therefore, theaforesaid limitation(s) or exclusion(s) may not apply to thepurchaser. This warranty gives you specific legal rights and you may also haveother rights which vary from state to state.

We Service What We Sell 9/94


Documents

Bio & Station Info - ProbeScope V4.1 for Windows/DOSCat. No. 22-310 OWNER’S MANUAL Please read before using this equipment. ProbeScope V4.1 for Windows/DOS 22-310.fm Page 1 Friday,