B+K precision 2522B Manual de usuario

20 MHz DIGITAL STORAGE/ANALOG

OSCILLOSCOPE

BK PRECISION

INSTRUCTION

MANUAL MODEL 2522B

BK PRECISION

TEST INSTRUMENT SAFETY

WARNING

Normal use of test equipment exposes you to a certain amount of danger from electrical shock because

testing must often be performed where exposed high voltage is present. An electrical shock causing

10 milliampsof current topass through theheartwill stopmost humanheartbeats.Voltageaslow as 35 volts

dc or ac rms should be considered dangerous and hazardous since it can produce a lethal current under

certain conditions. Higher voltage poses an even greater threat because such voltage can more easily

produce a lethal current. Your normal work habits should include all accepted practices that will prevent

contact with exposed high voltage, and that will steer current away from your heart in case of accidental

contact with a high voltage. You will significantly reduce the risk factor if you know and observe the

following safety precautions:

1. Don’t expose high voltage needlessly in the equipment under test. Remove housings and covers only when necessary.

Turn off equipment while making test connections in high-voltage circuits. Discharge high-voltage capacitors after

removing power.

2. If possible, familiarize yourself with the equipment being tested and the location of its high voltage points. However,

remember that high voltage may appear at unexpected points in defective equipment.

3. Use an insulated floor material or a large, insulated floor mat to stand on, and an insulated work surface on which to

place equipment; make certain such surfaces are not damp or wet.

4. Use the time-proven “one hand in the pocket” technique while handling an instrument probe. Be particularly careful to

avoid contacting a nearby metal object that could provide a good ground return path.

5. When using a probe, touch only the insulated portion. Never touch the exposed tip portion.

6. When testing ac powered equipment, remember that ac line voltage is usuallypresent on some power input circuits such

as the on-off switch, fuses, power transformer, etc. any time the equipment is connected to an ac outlet, even if the

equipment is turned off.

7. Some equipment with a two-wire ac power cord, including some with polarized power plugs, is the “hot chassis” type.

This includes most recent television receivers and audio equipment. A plastic or wooden cabinet insulates the chassis

to protect the customer.When the cabinet is removed forservicing, a serious shockhazard exists if thechassis is touched.

Not only does this present a dangerous shock hazard, but damage to test instruments or the equipment under test may

result from connecting the ground lead of most test instruments (including this oscilloscope) to a “hot chassis”. To make

measurements in “hot chassis” equipment, always connect an isolation transformer between the ac outlet and the

equipment under test. The B+K Precision Model TR-110 or 1604A Isolation Transformer, or Model 1653A or 1655A

AC Power Supply is suitable for most applications. To be on the safe side, treat all two wire ac powered equipment as

“hot chassis” unless you are sure it has an isolated chassis or an earth ground chassis.

8. Never work alone. Someone should be nearby to render aid if necessary. Training in CPR (cardio-pulmonary

resuscitation) first aid is highly recommended.

This symbol on oscilloscope means “refer to instruction manual

for further precautionary information”. This symbol appears in the

manual where the corresponding information is given.

Instruction Manual

for

Model 2522B

20 MHz

Digital Storage/Analog

Oscilloscope

1031 Segovia Circle, Placentia, CA 92870

BK PRECISION

TABLE OF CONTENTS

Page Page

TEST INSTRUMENT SAFETY . . . . . . inside front cover

FEATURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

CONTROLS AND INDICATORS . . . . . . . . . . . . . . . . . . 7

General Function Controls. . . . . . . . . . . . . . . . . . . . . . 7

Vertical Controls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Horizontal Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Triggering Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Digital Storage Controls. . . . . . . . . . . . . . . . . . . . . . . 10

Rear Panel Controls . . . . . . . . . . . . . . . . . . . . . . . . . . 10

OPERATING INSTRUCTIONS. . . . . . . . . . . . . . . . . . . 11

Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Equipment Protection Precautions. . . . . . . . . . . . . . . 11

Operating Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Initial Starting Procedure . . . . . . . . . . . . . . . . . . . . . . 12

Single Trace Display . . . . . . . . . . . . . . . . . . . . . . . . . 12

Dual Trace Display. . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Triggering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Magnified Sweep Operation . . . . . . . . . . . . . . . . . . . 15

X−Y Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Video Signal Observation. . . . . . . . . . . . . . . . . . . . . . 15

OPERATING INSTRUCTIONS (Continued)

Digital Storage Operation . . . . . . . . . . . . . . . . . . . . . 15

Applications Guidebook . . . . . . . . . . . . . . . . . . . . . . 17

MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Fuse Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Line Voltage Selection. . . . . . . . . . . . . . . . . . . . . . . . 18

PeriodicAdjustments. . . . . . . . . . . . . . . . . . . . . . . . . 18

Calibration Check . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Instrument Repair Service. . . . . . . . . . . . . . . . . . . . . 19

APPENDIX I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Important Considerations for Rise Time and

Fall Time Measurements . . . . . . . . . . . . . . . . . . . . 20

APPENDIX II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Unique Characteristics of Digital Storage

Oscilloscopes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Aliasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Equivalent Time Sampling . . . . . . . . . . . . . . . . . . . . 21

Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

“Guidebook To Oscilloscopes”

Availability . . . . . . . . . . . . . . . . . . . . . inside back cover

FEATURES

LOW COST, HIGH PERFORMANCE

B+K Precision’s Model 2522B is one of the lowest cost

digital storage oscilloscopes in the industry, yet it includes

all the basic features needed by most technicians and engi-

neers. Unlike other digital oscilloscopes, it has a full analog

modewith infiniteresolution.Digital storagemodesinclude

refresh, roll, and single sweep. Equivalent time storage

techniques allow storage of repetitive waveforms up to

20 MHz. This oscilloscope is built by and backed by B+K

Precision, a company that has been selling reliable,durable,

value priced test instruments for over 50 years.

DIGITAL STORAGE FEATURES

High Resolution

2048 samples across the width of the screen (200

samplesperdivision)assuresgoodresolutionofstored

waveforms. 1024 samples taken at sweep rates of

10 µs/div to 0.1 µs/div.

High Sampling Rate

Sampling Rate up to 10 Ms/s (Megasamples per sec-

ond) for storing one-time events down to 50 nS.

Slow Event Display

X100 time base selections extend sweep time to 50

seconds/division. Excellent for displaying slow speed

events.

Equivalent Time Sampling

Allows repetitive waveforms up to 20 MHz to be

stored.

Pretrigger Capture

Permits viewing activity before the trigger occurs.

Selectable 0%, 25%, 50%, or 75% pre-trigger view.

Plotter Output

Analog output plus TTL Pen-Down control for strip

chart recorder or X-Y plotter.

CRT FEATURES

Rectangular CRT

Rectangular CRT with large 8 x 10 centimeterviewing

area.

Convenience

Trace rotation electricallyadjustable from front panel.

0%, 10%, 90%, and 100% markers for risetimemeas-

urements.

DUAL TRACE FEATURES

Dual Trace

Model 2522B has two vertical input channels for dis-

playing two waveforms simultaneously. Selectable

single trace (either CH 1 or CH 2) or dual trace.

Alternate or chop sweep selectable at all sweep rates.

Sum and Difference Capability

Permits algebraic addition or subtraction of channel 1

and channel 2 waveforms, displayed as a single trace.

Useful for differential voltage and distortion measure-

ments.

HIGH FREQUENCY FEATURES

Wide Bandwidth

Conservatively-rated −3 dB bandwidth is dc to 20

MHz.

Fast Rise Time

Rise time is less than 18 nS.

Fast Sweep

Maximum sweep speed of 10 nS/div (with X10 MAG)

assures high frequencies and short-duration pulses are

displayed with high resolution.

VERTICAL FEATURES

High Sensitivity

5 mV/div sensitivity for full bandwidth. High-sen-

sitivity 1 mV/div and 2 mV/div using PULL X5 gain

control.

Calibrated Voltage Measurements

Accurate voltage measurements (±3%) on 10 cali-

brated ranges from 5 mV/div to 5 V/ div. Vertical gain

fully adjustable between calibrated ranges.

SWEEP FEATURES

Calibrated Time Measurements

Accurate (±3%) time measurements. The main sweep

has 21 calibrated ranges from 0.5 s/div to 0.1 µS/div.

Sweep time is fully adjustable between calibrated

ranges.

X10 Sweep Magnification

Allows closer examination of waveforms, increases

maximum sweep rate to 10 nS/div.

TRIGGERING FEATURES

Two Trigger Modes

Selectable normal (triggered) or automatic sweep

modes.

Triggered Sweep

Sweep remains at rest unless adequate trigger signal is

applied. Fully adjustable trigger level and (+) or (−)

slope.

AUTO Sweep

Selectable AUTO sweep provides sweep without trig-

ger input, automatically reverts to triggered sweep

operation when adequate trigger is applied.

Five Trigger Sources

Five trigger source selections, including CH 1, CH 2,

alternate, EXT, and LINE.

Video Sync

Frame (TV V) or Line (TV H) triggering selectablefor

observing composite video waveforms.TV-H position

can also be used as low frequency reject and TV-V

position can be used as high frequency reject.

Variable Holdoff

Trigger inhibit period after end of sweep adjustable.

Permits stable observation of complex pulse trains.

OTHER FEATURES

X−Y Operation

Channel 1 can be applied as horizontal deflection

(X-axis) while channel 2 provides vertical deflection

(Y-axis).

Built-in Probe Adjust Square Wave

A 0.5 V p-p, 1 kHz square wave generator permits

probe compensation adjustment.

Channel 2 (Y) Output

A buffered 50Ωoutput of the channel 2 signal is

available at the rear panel for driving a frequency

counter or other instruments. The output is 50 mV/div

(nominal) into 50Ω.

Supplied With Two Probes

FEATURES

SPECIFICATIONS

CRT

Type: 6-inch rectangular with integral graticule, P31

phosphor.

DisplayArea: 8 x 10 div (1 div = 1 cm).

AcceleratingVoltage: 2kV.

Phosphor: P31.

Trace Rotation: Electrical, front panel adjustable.

VERTICAL AMPLIFIERS (CH 1 and CH 2)

Sensitivity: 5 mV/div to 5 V/div, 1 mv/div to 1 V/div at

X5 MAG.

Attenuator: 10 calibrated steps in 1-2-5 sequence. Vernier

control provides fully adjustable sensitivity between

steps; range 1/1 to at least 1/3.

Accuracy: ±3%, 5 mV to 5 V/div; 5%, at X5 MAG.

Input Resistance:1MΩ±2%.

Input Capacitance: 25 pF ±10 pF.

Frequency Response:

5 mV/div to 5 V/div:

DC to 20 MHz (−3 dB).

X5 MAG:

DC to 10 MHz (−3 dB).

Rise Time:

18 nS; 35 nS at X5 MAG.

Overshoot: Less than 5%.

Operating Modes:

CH 1: CH 1, single trace.

CH 2: CH 2, single trace.

DUAL: CH 1 and CH 2, dual trace.

Alternate or Chop selectable at

any sweep rate.

ADD: Algebraic sum of CH 1 + CH 2.

Chop Frequency: Approximately 500 kHz.

Polarity Reversal: CH 2 invert.

Maximum Input Voltage: 400 V (dc + ac peak).

HORIZONTAL AMPLIFIER

(Input through channel 1 input)

X−Y mode:

CH 1 = X axis.

CH 2 = Y axis.

Sensitivity: Same as vertical channel 2.

Input Impedance: Same as vertical channel 2.

Frequency Response:

DC to 1 MHz (−3 dB).

X-Y Phase Difference: 3° or less at 50 kHz.

Maximum Input Voltage: Same as vertical channel 1.

SWEEP SYSTEM

Time Base: 0.1 µS/div to 0.5 S/div in 1-2-5 sequence,

21 steps. Vernier control provides fully adjustable

sweep time between steps.

Accuracy: ±3%, except ±20% on 0.1 µS/div.

Sweep Magnification: X10 ±10%.

Holdoff: Continuously adjustable for main time base from

NORM to 5 times normal.

TRIGGERING

Trigger Modes:

AUTO (free run), NORM, TV-V, TV-H.

Trigger Source:

CH 1, CH 2, Alternate, EXT, LINE.

Slope:

(+) or (–).

Trigger Coupling:

AUTO: Sweep free-runs in absence of

suitable trigger signal.

NORM: Sweep triggered only by adequate

trigger signal.

TV-V: Video vertical sync pulses are

selected. Also usable for high

frequency reject.

TV-H: Video horizontal sync pulses are

selected. Also usable for low

frequency reject.

Trigger Sensitivity:

AC: 1.0 div (internal)

≥0.5 Vp-p (external)

30 Hz – 30 MHz

TV-V: 1.0 div (internal)

≥0.5 Vp-p (external)

20 Hz – 30 kHz

TV-H: 1.0 div (internal)

≥0.5 Vp-p (external)

3 kHz – 100 kHz

Maximum External Trigger Voltage: 300 V (dc + ac

peak).

DIGITAL STORAGE FACILITIES

Storage Word Size:

2048 38 bits/channel (2 k/channel with direct sam-

pling, 1 k/channel with equivalent time sampling).

Vertical Resolution:

8 bit (1 in 256) approximately 25 steps/div.

Horizontal Resolution:

1 in 2048, approximately 200 samples/div.

Sampling Rate:

10 M samples/sec to 4samples/sec, reducedin propor-

tion to time base. Direct sampling at time base settings

of 20 µs/div and slower, equivalent time sampling at

time base settings of 10 µs/div and faster.

Time Base Expander:

For storage of slow time events, time base steps

10 ms/div andslower have selectable1/1 or 1/100 rate.

1/100 rate expands time base from 1 sec/div to 50

sec/div in 1-2-5 sequence.

Equivqlent Time Sampling Bandwidth:

20 MHz for repetitive waveforms.

Dot Joining:

Linear interpolation between samples.

Digital Display Modes:

Roll:

Stored data and display updated continually.

Refresh:

Storeddataanddisplayupdatedbytriggeredsweep.

Hold:

Freezes channel 1 and channel 2 data immediately.

Save CH 2:

Freezes channel 2 data immediately.

Pretrigger Storage:

Available in single sweepmode, switchable to 0%,

25%, 50%, or 75%.

PLOT OUTPUT

Analog output of the stored display.

CH 1 and CH 2 Outputs:

Selected by PLOT switch. Output via CH1 OUTPUT

and CH2 OUTPUT jacks on rear panel. Amplitude

0.2 V/div (2 V maximum).

Output Sweep Rate:

Output sweep rate is 1/10 of TIME/DIV setting (and

1/100 switch when applicable).

Pen Lift Output:

AvailableatPENDOWNjackonrearpanel,TTLhigh,

pen up. TTL low, pen down.

OTHER SPECIFICATIONS

Cal/Probe Compensation Voltage: 0.5 V p-p ±3% square

wave, 1 kHz nominal.

CH 2 (Y) Output:

Output Voltage: 50 mV/div (nominal into 50 ohm

load).

Output Impedance: Approximately 50 ohms.

Frequency Response: 20 Hz to 20 MHz, −3 dB.

Power Requirements: 100–130 VAC or 200–260 VAC,

50/60 Hz, 55 watts.

Dimensions (H 3W3D):

5.2″312.8″315.7″

(132 3324 3398 mm).

Weight: 18.7 lbs (8.5 kg).

Environment:

Within Specified Accuracy: +10° to +35° C, 10–80%

relative humidity.

Full Operation: 0° to +50° C, 10–80% relative

humidity.

Storage: −30° to +70° C, 10–90% relative humidity.

ACCESSORIES SUPPLIED:

Two Switchable X1/X10 Probes.

Instruction Manual.

AC Line Cord.

SPECIFICATIONS

CONTROLS AND INDICATORS

GENERAL FUNCTION CONTROLS

1. ON Indicator. Lights when oscilloscope is “on”.

2.POWER Pushbutton. Turns oscilloscope “on” and

“off”.

3.INTENSITY Control. Adjusts brightness of trace.

4.TRACE ROTATION Control. Adjusts to maintain

trace at a horizontal position.

5. FOCUS Control. Adjusts trace focus.

6. GND Terminal. Oscilloscope chassis ground

jack, and earth ground via three-wire ac power cord.

7. CAL Terminal. Terminal provides 0.5 V p-p, 1 kHz

(nominal) square wave signal. This signal isuseful for

checking probe compensation adjustment, as well as

providing a rough check of vertical calibration.

VERTICAL CONTROLS

8. VERTical MODE Switch. Selects vertical display

mode. Four-position lever switch with the following

positions:

CH1:

Displays the channel 1 signal by itself.

CH2/X-Y:

CH2: displays the channel 2 signal by itself.

X-Y: used in conjunction with the X-Y control and

Trigger SOURCE switch to enable X-Y display

mode.

DUAL:

Displays the channel 1 and channel 2 signals simul-

taneously. Dual-trace mode may be either alternate

orchoppedsweep;seethedescription underCHan-

nel 1 POSition/PULL CHOP control.

ADD:

The inputs from channel 1 and channel 2 are

summed and displayed as a single signal. If the

Channel 2 POSition/PULL INVert control is

pulled out, the input from channel 2 is subtracted

from channel 1 and the difference is displayed as a

single signal.

9. CH1 AC-GND-DC Switch. Three-position lever

switch with the following positions:

AC:

Channel 1 input signal is capacitively coupled; dc

component is blocked.

GND:

Opens signal path and grounds input to vertical

amplifier. This provides a zero-volt base line, the

position of which can be used as a reference when

performing dc measurements.

Fig. 1. Model 2522B Controls and Indicators.

1313 26 14 25 24 23 22 21

2718

37 30 31 36 33

29 32 34

38 35

DC:

Direct coupling of channel 1 input signal; both ac

and dc components of signal produce vertical de-

flection.

10. CH1 (X) Input Jack. Vertical input for channel 1.

X-axis input for X-Y operation.

11.CH1 (X) VOLTS/DIV Control. Vertical attenuator

for channel 1. Provides step adjustment of vertical

sensitivity. When channel 1 VARiable control is set

to CAL, vertical sensitivity is calibrated in 10 steps

from 5 mV/div to 5 V/div in a 1-2-5 sequence. When

the X-Y mode of operation is selected, this control

provides step adjustment of X-axis sensitivity.

12. CH1 VARiable/PULL X5 MAG Control:

VARiable:

Rotation provides vernier adjustment of channel 1

vertical sensitivity. In the fully-clockwise (CAL)

position, the vertical attenuator is calibrated. Coun-

terclockwise rotation decreases gain sensitivity. In

X-Y operation, this control becomes the vernier

X-axis sensitivity control.

PULL X5 MAG:

When pulled out, increases vertical sensitivity by a

factor of five. Effectively provides two extra sensi-

tivity settings: 2 mV/div and 1 mV/div. In X-Y

mode, increases X-sensitivity by a factor of five.

13. CH1 POSition/PULL CHOP Control:

POSition:

Adjusts vertical position of channel 1 trace.

PULL CHOP:

When this switch is pulled out in the dual-trace

mode, the channel 1 and channel 2 sweeps are

chopped and displayed simultaneously (normally

used at slower sweep speeds). When it is pushed in,

the two sweeps are alternately displayed, one after

the other (normally used at higher sweep speeds).

14. CH2 POSition/PULL INVert Control:

POSition:

Adjusts verticalposition of channel 2 trace. In X-Y

operation, rotation adjusts vertical position of X-Y

display.

PULL INVert:

When pushed in, the polarity of thechannel 2signal

is normal. When pulled out, the polarity of the

channel 2 signal is reversed, thus inverting the

waveform.

15. CH2 VOLTS/DIV Control. Vertical attenuator for

channel 2. Provides step adjustment of vertical sensi-

tivity. When channel 2 VARiable control is set to

CAL, vertical sensitivity is calibrated in 10 steps from

5 mV/div to 5 V/div in a 1-2-5 sequence. When the

X-Y mode of operation is selected, this control pro-

vides step adjustment of Y-axis sensitivity.

16. CH2 VARiable/PULL X5 MAG Control:

VARiable:

Rotation provides vernier adjustment of channel 2

vertical sensitivity. In the fully-clockwise (CAL)

position, the vertical attenuator is calibrated. Coun-

terclockwise rotation decreases gain sensitivity. In

X-Y operation, this control becomes the vernier

Y-axis sensitivity control.

CONTROLS AND INDICATORS

Fig. 2. Rear Panel Controls and Indicators.

41 42

43 43

++ +

+ +

SELECTOR LINE VOLTAGE FUSE

+ +

LINE VOLTAGE SLELCTOR

110

WARNING

SERIALNO’

CH1

OUTPUT CH2

OUTPUT PEN

DOWN

(ANALOG)

OUTPUT

PLOT OUTPUT

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