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
10milliampsofcurrentto pass throughtheheart will stop most human heartbeats. Voltageas low 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
contactwitha high voltage.Youwillsignificantlyreducetherisk factorifyouknow and observethefollowing
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 usually present 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
toprotect the customer. When the cabinet is removed for servicing, a serious shock hazard exists if the chassis 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.
®
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1031 Segovia Circle, Placentia, CA 92870
TABLE OF CONTENTS
PagePage
TEST INSTRUMENT SAFETY . . . . . . inside front cover
B+K Precision Model 2190B is one of the most economical 100 MHz analog oscilloscopes on the market, yet it has
all of the high performance features needed for most applications,including delayed time base, bandwidth limiter,and
Y axis output. 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.
CRT FEATURES
Rectangular CRT
Rectangular CRTwith large 8 x 10 centimeterviewing
area.
Convenience
Tracerotation electrically adjustable from front panel.
0%, 10%, 90%, and 100% markers for rise time measurements.
DUAL TRACE FEATURES
Dual Trace
Model 2190B has two vertical input channels for displaying 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 differentialvoltageand distortion measurements.
HIGH FREQUENCY FEATURES
Wide Bandwidth
Conservatively-rated −3dBbandwidthisdcto
100 MHz.
Fast Rise Time
Rise time is less than 3.5 ns.
Fast Sweep
Maximum sweep speed of 2 ns/div (with X10 MAG)
assures high frequencies and short-duration pulses are
displayed with high resolution.
VERTICAL FEATURES
High Sensitivity
5 mV/div sensitivityfor full bandwidth. High-sensitivity 1 mV/div and 2 mV/div using PULL X5 gain
control.
Calibrated VoltageMeasurements
Accurate voltage measurements (±3%) on 10 calibrated 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 23 calibrated ranges from 0.5 S/div to 20 nS/div.
The delayed sweep also has 23 calibrated ranges from
0.5 S/div to 20 nS/div. Sweep time is fully adjustable
between calibrated ranges.
X10 Sweep Magnification
Allows closer examination of waveforms, increases
maximum sweep rate to 2 nS/div.
DUAL TIME BASE FEATURES
Dual Sweep Generators
Main sweep gives normal waveform display, delayed
sweepmaybe operated atfastersweep speedtoexpand
a portion of the waveform.
Four Sweep Modes
Choice of main sweep only, delayed sweep only,
main sweep and delayed sweep sharing the trace
(percentage of mai n/d elaye d sweep adjustable), or
X−Y.
Adjustable Start Of Delayed Sweep
DELAYTIME POSition control allows adjustment of
delayed sweep starting point.
TRIGGERING FEATURES
Two TriggerModes
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.
3
FEATURES
AUTO Sweep
Selectable AUTO sweep provides sweep without trigger input, automatically reverts to triggered sweep
operation when adequate trigger is applied.
Five TriggerSources
Five trigger source selections, including CH 1, CH 2,
alternate, EXT, and LINE.
Video Sync
Frame(TV V) or Line (TV H) triggering selectablefor
observingcomposite video waveforms.TV-Hposition
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
Bandwidth Limiter
Selectablefullbandwidthof100mHzorlimitedbandwidth of 20 MHz to filter high frequency noise from
low frequency waveforms.
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 2 V p-p, 1 kHz square wave generator permits probe
compensation adjustment.
Channel 2 (Y) Output
A buffered 50Ω output 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.