Good Will Instrument instek GOS-6200 User manual

GOS-6200 OSCILLOSCOPE
USER MANUAL
⎯i ⎯
CONTENTS PAGE
1.
PRODUCT INTRODUCTION................................................. 1-1.Description……………………………………………….
1-2.Feature…………………………………………………....
1
1
2
2. TECHNICAL SPECIFICATIONS…………………………
4
3. PRECAUTIONS BEFORE OPERATION…….…………...
3-1.Unpacking the instrument………………….…………....
3-2.Checking the Line Voltage…………………..…………..
3-3.Environment……………………………………..………
3-4.Equipment Installation and Operation………………....
3-5.CRT Intensity……………………………………………
3-6.Withstanding Voltage of Input Terminals……………...
8
8
8
9
9
9
9
4. PANEL INTRODUCTION……………………..…………...
4-1.Front Panel……………………………………………….
4-2.Rear Panel……………………………………….……….
10
12
34
5. OPERATION METHOD………………………………...….
5-1.Readout Display……………………………………..…...
5-2.Connecting Input Signals..………………………………
5-3.Adjustment and Checks…………………………………
5-4.Function Check…..………………………………………
5-5.Basic Operation………….….…………………………....
5-6.Measurement Application……………………………….
36
36
38
39
41
43
52
6. MAINTENANCE……………………………………………
6-1.Fuse Replacement………………………………………..
6-2.Line Voltage…………………………………………..….
6-3.Cleaning………………………………………………….
56
56
56
57
7. BLOCK DIAGRAM………………………………………... 58
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USER MANUAL
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SAFETY TERMS AND SYMBOLS
These terms may appear in this manual or on the product:
WARNING. Warning statements identify condition or
practices that could result in injury or loss of life.
CAUTION. Caution statements identify conditions or
practices that could result in damage to this product or
other property.
The following symbols may appear in this manual or on the product:
DANGER ATTENTION Protective Earth(ground)
High Voltage refer to Manual Conductor Terminal
Terminal

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USER MANUAL
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FOR UNITED KINGDOM ONLY
NOTE: This lead/appliance must only be wired by competent persons
WARNING: THIS APPLIANCE MUST BE EARTHED
IMPORTANT: The wires in this lead are coloured in accordance with
the following code:
Green/ Yellow: Earth
Blue: Neutral
Brown: Live (Phase)
As the colours of the wires in main leads may not correspond with the
colours marking identified in your plug/appliance, proceed as follows:
The wire which is coloured Green & Yellow must be connected to the
Earth terminal marked with the letter E or by the earth symbol
or coloured Green or Green & Yellow.
The wire which is coloured Blue must be connected to the terminal
which is marked with the letter N or coloured Blue or Black.
The wire which is coloured Brown must be connected to the terminal
marked with the letter L or P or coloured Brown or Red.
If in doubt, consult the instructions provided with the equipment or
contact the supplier.
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USER MANUAL
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This cable/appliance should be protected by a suitably rated and
approved HBC mains fuse: refer to the rating information on the
equipment and/or user instructions for details. As a guide, cable of
0.75mm2should be protected by a 3A or 5A fuse. Larger conductors
would normally require 13A types, depending on the connection
method used.
Any moulded mains connector that requires removal /replacement
must be destroyed by removal of any fuse & fuse carrier and disposed
of immediately, as a plug with bared wires is hazardous if a engaged
in live socket. Any re-wiring must be carried out in accordance with
the information detailed on this label.

GOS-6200 OSCILLOSCOPE
USER MANUAL
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EC Declaration of Conformity
We
GOOD WILL INSTRUMENT CO., LTD.
No. 7-1, Jhongsing Rd., Tucheng City, Taipei County 236, Taiwan
GOOD WILL INSTRUMENT (SUZHOU) CO., LTD.
No.69 Lushan Road, Suzhou New District Jiangsu, China.
declares that the below mentioned product
GOS-6200
is herewith confirmed to comply with the requirements set out in the Council Directive
on the Approximation of the Law of Member States relating to Electromagnetic
Compatibility (89/336/EEC, 92/31/EEC, 93/68/EEC) and Low Voltage Equipment
Directive (73/23/EEC, 93/68/EEC).
For the evaluation regarding the Electromagnetic Compatibility and Low Voltage
Equipment Directive, the following standards were applied:
EN 61326-1: Electrical equipment for measurement, control and laboratory use ––
EMC requirements (1997+A1: 1998)
Conducted and Radiated Emissions
EN 55011 class B: 1998 Electrostatic Discharge EN 61000-4-2: 1995
Current Harmonic
EN 61000-3-2: 1995 Radiated Immunity EN 61000-4-3: 1996
Voltage Fluctuation
EN 61000-3-3: 1995 Electrical Fast Transients EN 61000-4-4: 1995
———————————————— Surge Immunity
EN 61000-4-5: 1995
———————————————— Conducted Susceptibility
EN 61000-4-6: 1996
———————————————— Power Frequency Magnetic field
EN 61000-4-8: 1993
———————————————— Voltage Dips/ Interrupts
EN 61000-4-11: 1994
Low Voltage Equipment Directive 73/23/EEC & amended by 93/68/EEC
Safety Requirements
IEC/EN 61010-1: 2001
GOS-6200 OSCILLOSCOPE
USER MANUAL
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1.PRODUCT INTRODUCTION
1-1. Description
The GOS-6200 is a 200MHz, two-channel, dual-sweep, portable oscilloscope
for general purpose use. A microprocessor-based operating system controls
most of the functions of the instrument, including cursor readout and
digitized panel setting. On-screen alphanumeric readout and cursor function
for voltage, time, frequency and phase measurement provide extraordinary
operational convenience. Also, the function of TV Line select for triggering
setting, auto measurement for frequency, period, pulse width and duty cycle
and auto setting function. Ten different user defined instrument settings can
be saved and recalled without restriction.
The vertical deflection system has two input channels. Each channel has 11
basic deflection factors from 2mV to 5V per division. The horizontal
deflection system provides single, dual or delayed sweeps from 0.5s to 20ns
per division (delayed sweep, 50ms to 20ns per division). The trigger system
provides stable triggering over the full bandwidth of the vertical deflection
system.

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1-2.Features
Additionally, the oscilloscope offers several other features:
1) High intensity and internal graticule CRT
The oscilloscope employs a high intensity 6-inch retangular type
cathode-ray tube with red internal graticule. It displays clear readable
traces even at high sweep speeds. Internal graticule lines eliminate
parallax-viewing error between the trace and the graticule line.
2) Temperature compensation
The oscilloscope uses a temperature compensation circuit to reduce the
drift of base line and DC balance.
3) 20MHz bandwidth limit
When it is hard to observe or trigger a signal because a high-frequency
component is superimposed on the signal, use the 20MHz BWL
function to reduce the bandwidth of the vertical deflection system and
trigger system to 20MHz.
4) Auto-setting
At a press of the AUTOSET button, an optimum time base range is
automatically set to a corresponding change in input signal period. A
signal period from 1.6 to 4 cycles, signal amplitude from 1~7 div
approx. is displayed.
5) TV triggering
Exclusive TV sync separator circuit technology provides stable TV
signal measurements on fields, frames and lines.
6) Z-axis intensity modulation
For applying a blanking signal from an external source. The trace
displayed on the screen may be intensity-modulated where pulse signal
or time-scale marks are required.
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7) Trigger signal output
The signal selected by the TRIGGER SOURCE is available. This
output may be used to connect to a frequency counter or other
instrument.
8) Panel setups lock
To avoid unintentional touch of the setting, the feature is extremely
useful for long term and repetitive measurements that used to be
performed under the same test condition of the oscilloscope setting.
9) LED indicator and buzzer alarm
The LED’s located in the front panel assist operation and indicated
additional information. Incorrect operation and the electrical end
position of control knobs are indicated by a warning beep.
10)SMD manufacturing technology
The instrument is built by using the most advanced SMD technology
so as to reduce the number of internal wiring and shorten the foil route
on the pc board. This will also greatly increase the high frequency
performance and the reliability of the product.
11)Auto Measurement
A built-in 6 digits universal counter is accurate within the range of ±
0.01% and can measure frequency between 50Hz and 200MHz.

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2.TECHNICAL SPECIFICATIONS
Sensitivity 2mV~5V/DIV, 11 steps in 1-2-5 sequence
Sensitivity Accuracy ±3% (5 DIV at the center display )
Vernier Vertical Sensitivity Continuously variable to 1/2.5 or less than
panel-indicated value
Frequency Bandwidth(-3dB) DC ~ 200MHz (5mV/DIV:DC~150MHz)
(2mV/DIV:DC ~ 20MHz)
Rise Time 1.75ns(5mV/DIV:2.33ns) (2mV/DIV:17.5ns)
Signal Delay Leading edge can be monitored
Maximum Input Voltage 400V (DC+AC) at 1kHz or less
Input Coupling AC, DC, GND
Input Impedance 1MΩ±2% // 25pF approx.
Vertical Modes CH1,CH2,DUAL(CHOP/ALT),ADD(DIFF mode can
Be established when the CH2 is in the INV mode)
CHOP Repetition Frequency Approx. 250kHz.
Polarity (INV) CH2 only
Bandwidth Limited 20MHz
VERTICAL
DEFLECTION
SYSTEM
Common-mode
Rejection Ration 50:1 or better at 50kHz
Trigger Modes AUTO, NORM, TV
Trigger Source CH1, CH2, LINE, EXT. EXT/10
Trigger Coupling AC, DC, HFR, LFR, NR
Trigger Slope +/- polarity or TV sync polarity
Mode Frequency INT EXT
10Hz~20MHz 0.35DIV 50mVpp
AUTO 20MHz~200MHz 1.5DIV 150mVpp
DC~20MHz 0.35DIV 50mVppNORM 20MHz~200MHz 1.5DIV 150mVpp
Trigger Sensitivity
TV Sync signal 1DIV 200mVpp
Trigger Level Range INT : ± 4 DIV or more EXT : ± 0.4 V or more
EXT/10 : ± 4 V or more
TV-V, TV-H, TV-L
TV-Line Selection
Standard Field 1 Field 2
NTSC(525H) 1H~263H 1H~262H
PAL (625H)
TV Sync
SECAM(625H) 1H~313H 1H~312H
Max. External Input Voltage 400V (DC + AC peak) at 1kHz
TRIGGER
SYSTEM
External Input Impedance 1MΩ± 5% ∕∕25pF approx.
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Horizontal Modes MAIN(A), ALT, DELAY(B)
A (main) Sweep Time 20ns~0.5sDIV, continuously variable
(UNCAL)
B (delay) Sweep Time 20ns~50msDIV
Accuracy ± 3% (± 5% at × 10 MAG)
Sweep Magnification × 10 (maximum sweep time 2nS/DIV)
Hold Off time Variable
Delay Time 1us~5s
Delay Jitter 1/20000 or less
HORIZONTAL
DEFLECTION
SYSTEM
Alternate Separation Variable
Sensitivity Accuracy
X-axis, Y-axis selectable
X-axis: CH1, CH2Æ2mV~5V/DIV ± 3%
EXT Æ0.1V/DIV ± 5%
EXT/10 Æ1V/DIV ± 5%
Y-axis: CH1,CH2Æ2mV~5V/DIV ± 3%
X-axis Bandwidth DC~500kHz (-3dB)
X-Y
OPERATION
Phase Error 3°or less at DC~50kHz
Cursor Measurement Function ΔV,ΔV%,ΔVdB,ΔT,1/ΔT,ΔT%,Δ
Θ .
Cursor Resolution 1/100 DIV
Effective Cursor Range Vertical: ± 3 DIV; horizontal: ± 4 DIV
CURSOR
READOUT
FUNCTION
Panel setting Vertical: V/DIV (CH1,CH2),UNCAL, ADD,
INV, P10, AC/DC/GND.
Horizontal: S/DIV (MTB, DTB), UNCAL
x10MAG, Delay time, Hold-off.
Trigger: Source, Coupling, Slope, Level ,
TV-V/TV-H/TV-L.
Others: X-Y, LOCK, SAVE/RECALL
MEM0-9.
Parameter Function FREQ, PERIOD,±WIDTH, ±DUTY,
(+ or – polarity selected by trigger slop.)
Display Digits Max. 6-digits, decimal.
Frequency Range 50Hz~200MHz.
Accuracy 1kHz~200MHz: ±0.01%
50Hz~1kHz : ±0.05%
AUTO
MEASUREMENT
FUNCTION
Measuring Sensitivity >2div(measuring source selected from CH1
and CH2 as synchronous signal source.)

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Type 6-inch rectangular type with internal graticule 0%, 10%, 90% and 100% markers.
8 x10 DIV (1 DIV = 1 cm)
Phosphor P31
Accelerating Potential 14.5kV approx.
CRT
Illumination Continuous adjustable
External intensity modulation
Coupling DC
Voltage 5V or more
Maximum Input Voltage 30V (DC+AC peak) at 1kHz or less
Z-AXIS
INPUT Bandwidth DC~5MHz
Voltage 25mV/DIV approx. in 50Ωtermination
Frequency Response DC~10MHz
TRIGGER
SIGNAL
OUTPUT Output Impedance 50Ωapprox.
Waveform 1kHz ± 5%, square wave
Voltage 2Vpp ± 2%
CALIBRATOR
OUTPUT Impedance 2kΩapprox.
Auto Set Input Channel: CH1,CH2;
Frequency Response 50Hz~50MHz
Panel Setting Save & Recall 10 sets
SPECIAL
FUNCTION Panel Setups Lock Provided
Voltage AC 100V, 120V, 230V ±10% selectable
Frequency 50Hz or 60Hz
LINE POWER
REQUIREMENT Power Consumption Approx. 90VA, 75W(max.)
OPERATING
ENVIRONMENT
Indoor use
Altitude up to 2000 m
Ambient temperature :
To satisfy specifications : 10°to 35℃( 50°to 95°F )
Maximum operating ranges: 0°to 40℃( 32 °to 104°F )
Relative humidity:85% RH(max.) non condensing
Installation Category II
Pollution degree 2
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STORAGE
TEMPERATURE
& HUMIDITY -10°to 70℃, 70%RH(maximum)
Dimensions 310 W × 150 H × 485 D (mm)
MECHANICAL
SPECIFICATION Weight Approx. 9.5kgs (20.9 lbs)
ACCESSORIES Power cord….............……….. 1
Instruction manual…………… 1
Probe (×1/×10)…………..… 2

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3.PRECAUTIONS BEFORE OPERATION
3-1.Unpacking the Oscilloscope
The product has been fully inspected and tested before shipping from the
factory. Upon receiving the instrument, please unpack and inspect it to
check if there is any damages caused during transportation. If any sign of
damage is found, notify the bearer and/or the dealer immediately.
3-2.Checking the Line Voltage
The oscilloscope can be applied any kind of line voltage shown in the
table below. Before connecting the power plug to an AC line outlet, make
sure the voltage selector of the rear panel is set to the correct position
corresponding to the line voltage. It might be damaged the instrument if
connected to the wrong AC line voltage.
WARNING. To avoid electrical shock the power cord
protective grounding conductor must be connected to ground.
When line voltages are changed, replace the required fuses shown as below:
Line voltage Range Fuse Line voltage Range Fuse
100V
120V 90-110V 108-132V T 1A250V 230V 207-250V T 0.4A250V
WARNING. To avoid personal injury, disconnect the power
cord before removing the fuse holder.
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3-3.Environment
The normal ambient temperature range of this instrument is from 0°to
40°C (32°to 104°F). To operate the instrument over this specific
temperature range may cause damage to the circuits.
Do not use the instrument in a place where strong magnetic or electric
field exists as it may disturb the measurement.
3-4.Equipment Installation, and Operation
Ensure there is proper ventilation for the vents in the oscilloscope case. If
the equipment is used not according to the specification, the protection
provided by the equipment may be impaired.
3-5.CRT Intensity
To prevent permanent damage to the CRT phosphor, do not make the
CRT trace brighten excessively or leave the spot stay for an unreasonably
long time.
3-6.Withstanding Voltages of Input Terminals
The withstanding voltages of the instrument input terminals and probe
Input terminals are shown in the following table. Do not apply voltages
higher than these limits.
Input terminal Maximum input voltage
CH1, CH2, inputs 400V (DC + AC peak)
EXT TRIG input 400V (DC + AC peak)
Probe inputs 600V (DC + AC peak)
Z AXIS input 30V (DC + AC peak)
CAUTION. To avoid damaging the instrument, do not apply input
voltages of the frequency over 1 kHz to the instrument.

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4. PANEL INTRODUCTION
After the instrument is switched on, all the important settings are displayed
in the readout. The LED’s located on the front panel assist operation and
indicate additional information. Incorrect operation and the electrical end
positions of control knobs are indicated by a warning beep.
Except the Power pushbutton (POWER), the Focus control (FOCUS), the
Scale Illumination control (ILLUM) and the Trace Rotation control, all
other controls are electronically selected, and their functions and settings
can therefore be stored.
The front panel is subdivided into six sections:
zDisplay controls
zVertical controls
zHorizontal controls
zTrigger controls
zMeasurement and SAVE/RECALL controls
zInput connectors
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Front panel of GOS-6200

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4-1.Front Panel
Display controls
The display controls adjust the on-screen appearance of the waveform and
provide a probe compensation signal source.
1 KHz
56 34
OFF
2 1
INTEN
CAL
2Vp-p
ILLUM ROTATION
FOCUS TRACE READOUT
TRACE/
ON/OFF POWER
(1).POWER – Pushbutton and symbols for ON(1) and OFF(0).
When switch on the oscilloscope to have all LEDs lighted and the
software version will be displayed on the screen. After the Internal test
is completed successfully, the normal operation mode is present. Then
the last settings become activated and the LED indicates the ON
condition.
(2).INTEN-TRACE/READOUT & READOUT ON/OFF— Control
knob with associated pushbutton and readout display.
The control knob is used for adjusting the traces and readout
intensity. Turning the knob clockwise to increase the intensity and
turning it counterclockwise to decrease the intensity.
The TRACE/READOUT pushbutton is for selecting the intensity
function and indicates the letter “TRACE INTEN” or “READOUT
INTEN” in the readout. Press the pushbutton briefly for the
following sequences:
“TRACE INTEN” — “READOUT INTEN” — “TRACE INTEN”
READOUT ON/OFF
Pressing and holding the TRACE/READOUT pushbutton switches
the readout on or off.
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(3).TRACE ROTATION
The TRACE ROTATION is for aligning the horizontal trace in
parallel with graticule lines. This potentiometer can be adjusted with a
small screwdriver.
(4).FOCUS
The control knob effects both the trace and the readout sharply.
(5).ILLUM
The knob controls the graticule illumination brightness.
(6).CAL
The terminal provides a reference signal of 2Vp-p at 1kHz for probe adjustment.
Vertical controls
The vertical controls select the displayed signals and control the
amplitude characteristics.
CURSOR
POS
CH1
GND
2mV
1917
AC/DC
VAR
Px10
8
13
15
7
5V
20MHz
VOLTS/DIV
BWL
V1/2
POSITION
9
18
AC/DC
VAR
Px10
20
GND
16
ALT / TRACE
VOLTS/DIV
5V
CHOP /
ADD
INV
CH2
2mV
14
SEP
11
12
POSITION
VERTICAL
C2C1
10

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(7).20MHz BWL – Pushbutton with indicator LED.
Briefly pressing the pushbutton, the bandwidth is reduced to approx.
20MHz, and the measurement is made by eliminating undesired high
frequency signal from the waveform. Also the high frequency
component over 20MHz is eliminated from the trigger signal.
(8).CURSOR POS - △V1/2 — Pushbutton with double function and
associated indicator LED.
The function of Cursor Position or CH1/CH2 Position can be selected
only after the pushbutton of Cursor Function is pressed to appear
enabling their cursor measurement. Press the pushbutton once briefly
to have the related LED lighted, the CH1/CH2 POSITION control
knob is then operated as CURSOR 1/CURSOR 2 POSITION control.
△V1/2
The function is required and available only in DUAL mode in
combination with △V (Voltage) measurement. Pressing and holding
the pushbutton, then switch between CH1 and CH2, the measured
result will be displayed by the readout with “△V1…” or “△V2…”
providing the defection coefficient is calibrated. The settings of the
cursors must be related to the signal of the selected channel.
(9).CH1 POSITION – C1 — Control knob with double function.
The vertical trace position of channel 1 can be set with the control knob,
which is also operated as CURSOR 1 position control in cursor
measurement mode.
(10)CH2 POSITION – C2 — Control knob has several functions.
The vertical trace position of channel 2 can be set with the control
knob, which is also operated as CURSOR 2 position control in cursor
measurement mode. In alternate time base mode, this control knob
can be used to separate the DELAY time base trace from the MIAN
time base trace. Please note TRACE SEP (11).
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(11)TRACE SEP
The instrument contains a trace separate function which is required in
the alternate time base mode to separate the DELAY time base trace(s)
from the MAIN time base in vertical direction. Consequently this
function is only available in alternate time base mode. Press the
pushbutton once to have the related LED lighted, the CH1 POSITION
control knob is then operated as vertical position control for the
trace(s) of the DELAY time base.
(12)ALT/CHOP/ADD-INV
The pushbutton has several functions, which are required and available
only when both channels are active.
ALT– Displays in the readout, indicates alternate channel switching.
After each time base sweeps the instrument internally, switches over
from channel 1 and channel 2 and vice versa.
CHOP– Indicates chopper mode.
The channel switching occurs constantly between channel 1 and
channel 2 during each sweep.
ADD– Displays in the readout, indicates additional mode.
Whether the algebraic sum (addition) or the difference (subtraction) of
both input signals is displayed, depends on the phase relationship and
the INV setting. As a result, both signals are displayed as one signal.
For correct measurements, the deflection coefficients for both channels
must be equal.
INV—Pressing and holding the pushbutton to set the channel 2 invert
function on or off. The invert on condition is indicated with a horizontal
bar above “CH2” in the readout. The invert function causes the signal
display of channel 2 to be inverted by 180o.

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(13)CH1 VOLTS/DIV.
(14)CH2 VOLTS/DIV– Control knob for channel 1/channel 2 has double
function.
Turning the knob clockwise to increase the sensitivity in 1-2-5 sequence
and turning it in the opposite direction (CCW) to decrease. The
available range is from 2mV/div up to 5V/div. The knob is
automatically switched inactive if the related channel is switched off.
The deflection coefficients and additional information regarding the
active channels are displayed in the readout.
ie. “CH1=deflection coefficient, input coupling”. The “=” symbolizes
calibrated measuring conditions and is replaced by the “>” symbol in
uncalibrated conditions.
(15)CH1-VAR.
(16)CH2-VAR — Pushbutton with double function.
CH1/CH2
Pressing briefly the CH1(CH2) button to set the cannel 1 (channel 2) of
the instrument on, the deflection coefficient will be displayed in the
readout indicating the current conditions (“CH1…”/ “CH2…”).
VAR
Pressing and holding the pushbutton to select the VOLTS/DIV function
between attenuator and vernier (variable). The current setting is
displayed by the “>” symbol in the readout.
After switching on the VAR, turn the VOLTS/DIV control knob
counterclockwise to reduce the signal height, and the deflection
coefficient becomes uncalibrated.
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(17)CH1 AC/DC.
(18)CH2 AC/DC
Pressing the pushbutton briefly to switch over from AC (~ symbol) to
DC (= symbol) input coupling. The setting is displayed in the readout
with the deflection coefficient.
(19)CH1 GND– P×10
(20)CH2 GND – P×10 –Pushbutton has two functions.
GND
Each time when the pushbutton is pressed briefly, the input of the
vertical amplifier is grounded. It is displayed in the readout as an earth
(ground) symbol “ ”.
P×10
Pressing and holding the pushbutton to select the indicated deflection
coefficient of the channel displayed in the readout between 1:1 and 10:1.
The probe factor of 10:1 is displayed in the readout with the probe
symbol in front of channel indication (e.g. “P10”, CH1) When proceed
cursor voltage measurement, the probe factor will be automatically
included. The symbol must not be activated unless a 10:1 attenuator
probes are used.

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Horizontal controls:
The horizontal controls select the time base operation mode and adjust the
horizontal scale, position and magnification of the signal.
: PUSH LONG
TIME/DIV
POSITION
HORIZONTAL
22
0.5S
21
23
DELAY
ALT /
MAIN /
SETUPS 24
X-Y
VAR
20nS
LOCK
25
MAG
x10
(21)TIME/DIV– Control knob with double function.
Turning the knob clockwise to reduce the deflection coefficient in a
1-2-5 sequence and turning it in the opposite direction (CCW) to
increase. The time coefficient(s) will be displayed in the readout.
In MAIN time base (MTB) mode, time deflection coefficients between
0.5s/div and 20ns/div can be chosen in 1-2-5 sequence, if the ×10
MAG function is not activated.
During alternate (ALT) and DELAY time base (DTB) operation, the
control knob changes the DELAY time base setting in 1-2-5 sequence.
The available deflection coefficient range is from 50ms/div up to
20ns/div (without ×10 MAG), but the availability depends on the
MAIN time base setting. The internal control of the oscilloscope
prevents the DELAY time deflection coefficient from becoming higher
than the MAIN deflection coefficient, as such an operation condition
would make no sense.
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(22)MAIN/ALT/DELAY— Pushbutton for time base mode selection.
The instrument contains two-time base designated MAIN and DELAY.
With the aid of the DELAY time base, signal parts displayed by the
MAIN time base can be expanded in X-direction. The expansion ratio
depends on the time deflection coefficient ratio of both time bases (ie.
“MTB=0.1ms”, “DTB=1μs”=100:1). With higher expansion ratio the
DELAY time base trace intensity reduces. Each time when press the
pushbutton briefly, the time base mode changes in the sequence of
MAIN-ALT-DELAY-MAIN. The actual setting is displayed in the
readout.
MAIN
The TIME/DIV control knob is operated only under the MAIN time
base mode. The readout then displays the main time coefficient alone.
The time base setting for this condition will be stored if the time base
mode is changed.
ALT
If the alternate time base mode is selected, the TIME/DIV knob only
controls the DELAY time base switch. The alternate time base mode is
a sub-function of the DELAY time base mode and both time base
traces can be displayed simultaneously. Consequently the readout can
display both time deflection coefficient. A window sector which
indicates part of signal is also visible on the MAIN trace and is
displayed by the DELAY time base.
The window segment can be shifted horizontally by the DELAY TIME
control continuously. The difference between the beginning of both the
MAIN time base trace and the window sector shows the delay time.
The information is also displayed in the readout with an approximate
value (e.g. “DLY=0.125ms”) related to the calibrated MAIN time
coefficient (uncalibrated i.e. “DLY>0.125ms”). The width of the

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USER MANUAL
⎯20 ⎯
window segment decreases when the DELAY time coefficient is set to
a lower value (higher time deflection speed).
For better reading, the vertical position of the DELAY time base trace
position can be shifted (please note TRACE SEP (11)).
DELAY
In the DELAY time base mode, the display of the MAIN traces, the
window sector and the MAIN time coefficient will disappear from the
readout. As the trace separation is no longer required under the
circumstances, the function would be switched off too. Consequently,
only the DELAY time coefficient is displayed by the readout.
(23)H POSITION
The control knob enables a horizontal position shift of the signals. In
combination with ×10 MAG the function makes it possible to shift any
part of the signal on the screen.
(24)×10 MAG—SETUPS LOCK— Pushbutton has double function and
associated MAG LED.
Each time when this pushbutton is pressed, the MAG LED located
above will be switch on or off. If the MAG LED is lighted, the signal
display in all time base modes will be expanded 10 folds and
consequently only a tenth part of the signal curve is visible. The
interesting part of the signal can be made visible with the aid of the H.
POSITION control.
SETUPS LOCK
Pressing and holding the pushbutton, then switch the panel setups lock
function on or off. To avoid unintentional touch of the setting, the
feature is extremely useful for long term and repetitive measurements
that need to be performed under the same test condition of the
oscilloscope setting.
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⎯21 ⎯
(25)X-Y-VAR – Pushbutton with double function.
X-Y
Set to X-Y mode to select three functions sequentially by pressing the
button briefly.
VAR
Pressing and holding the pushbutton to select the TIME/DIV (21)
control knob function between time base switch and vernier (variable).
The variable function is activated in the MAIN time base only.
After switching on the VAR, the time deflection coefficient is still
calibrated until further adjustments are made. Turn the TIME/DIV (21)
control knob counter clockwise to increase the time deflection
coefficient (reduce the deflection speed) and the deflection coefficient
becomes uncalibrated. Instead of “A=10μs”, the readout then displays
“A>10μs” indicating the uncalibrated condition. This setting is stored
if the instrument is switched to ALT or DELAY time base mode.
Switch off the VAR by pressing and holding the pushbutton of time
base mode again, then set the time deflection coefficient back into the
calibrated condition.

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⎯22 ⎯
Trigger controls
The trigger controls determine the sweep start timing for both signal and
dual trace operation.
TV
POLA
SYNC
32 31
27
26
HO
DELAY TIME
EXT
E/10
CH2
SLOPE
NML
TV
TV-H /
TV-V /
TV-L STD
FLD1/2
LFR
NR
HFR
DC
SOURCE
CH1
LEVEL
TRIGGER
MODE
ATO
-
COUPLING
TV LINE
AC
SELECT+
28
29
30
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⎯23 ⎯
(26)MODE – Pushbutton and indicator LEDs.
Pressing the pushbutton to select the trigger mode. The actual setting
is indicated by a LED.
Each time when the MODE pushbutton is pressed the trigger mode
changes in the sequence:
ATO—NML—TV—ATO
ATO (Auto)
Select the automatical mode, the sweep free-runs will display a
baseline trace when there is no trigger signal or the frequency is below
10Hz. The setting of triggering level changed only when the
TRIGGER LEVEL control is adjusted to a new level setting.
NML (Normal)
Select the normal mode, the input signal will trigger the sweep when
the TRIGGER LEVEL control is set within the peak-to-peak limits of
an adequate trigger signal. When the sweep is not triggered, no
baseline trace will be displayed.
TV
Separate the video sync signal from the composite waveform and
direct it to the triggering circuit. The horizontal or vertical sync signals
are selected by TV-V/TV-H/TV-STD pushbutton. Please refer to the
TV-V/TV-H/TV-STD (31).

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⎯24 ⎯
(27)TRIGGER LEVEL/TV LINE SELECT—Control knobs
TRIGGER LEVEL
Turning the control knob causes a different trigger input setting
(voltage), and set to a suitable position for the starting of triggered
sweep of the waveform. An approximate trigger level setting (voltage)
value will be displayed in the readout. When rotate clockwise the
control knob, the trigger point moves toward the positive peak of the
trigger signal and rotate it counterclockwise to move the trigger point
toward the negative peak of the trigger signal.
When the setting (voltage) value is out of the changing portion of the
observation waveform, the synchronization sweep stops. Sometimes a
“?” will be displayed on the left of the valued display, that indicates
that direct reading is impossible if AC, HFR, LFR, NR coupling or
VAR of vertical deflection is set.
TV LINE SELECT
If in the TV LINE trigger mode, the knob can only control the TV line
numbers.
(28)COUPLING/FLD 1/2 –Pushbutton and indicator LEDs.
Pressing the pushbutton to select the trigger coupling. The actual
setting is indicated by a LED and by the readout (“source, slope, AC”).
Each time when the COUPLING pushbutton is pressed the trigger
coupling changes in the sequence:
AC—DC—HFR—LFR—NR—AC
AC
Attenuates trigger signal frequency components below 10Hz and
blocks the DC component of the signal.
AC coupling is useful for triggering on AC waveforms that have a
large DC offset.
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⎯25 ⎯
DC
Couple DC and all frequency components of a triggering signal to the
trigger circuitry.
DC coupling is useful for most signals, especially for providing a
stable display of low-frequency or low-repetition-rate signals.
HFR (High Frequency Reject)
Attenuates high-frequency triggering signal components above 40kHz.
HFR coupling is useful for providing a stable display of low-frequency
components of complex waveforms and eliminates high-frequency
interference from the trigger signal.
LFR (Low Frequency Reject)
Attenuates low-frequency triggering signal components below 40kHz
and blocks the DC component of the trigger signal.
LFR coupling is useful for producing stable triggering on the
high-frequency components of complex waveforms and rejecting
low-frequency interference or power supply hum from the trigger
signal.
NR (Noise Reject)
Decrease the maximum trigger bandwidth for high frequency signals,
as in DC coupling condition, lower frequency signal parts are not
affected.
FLD 1/2
If set to TV LINE trigger mode, select the video field 1 or 2 (even or
odd) by pressing the pushbutton. When the pushbutton of FLD 1/2 is
pressed, the field 1 or 2 will be changed in the sequence as follows:
FLD 1—FLD 2—FLD 1

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⎯26 ⎯
(29)SOURCE—Pushbutton and associated LEDs.
Pressing the pushbutton to select the trigger signal source or the X
signal for an X-Y operation. The actual setting is indicated in a LED
and by the readout (“SOURCE”, slope, coupling).
CH1
The signal applied to the channel 1 input connector is the source of
the trigger signal.
CH2
The signal applied to the channel 2 input connector is the source of
the trigger signal.
(Line)
The triggering signal is obtained from a sample of the AC power
source waveform. The trigger source is useful when the displayed
waveform frequency is time related to the AC power source
frequency.
EXT
The external signal applied through the EXT input connector is used
for the external triggering source signal. When in the dual X-Y
operation, the X-axis operates with the external signal.
E/10(EXT/10)
The external signal applied through the EXT input is attenuated to
10:1 and connector is used for the external triggering source signal.
When in the dual X-Y operation, the X-axis operates with the
external signal.
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USER MANUAL
⎯27 ⎯
(30)HO-DELAY—Control knob with a double function and associated
LED.
The control knob has two different functions depending on the time
base mode.
HO (Hold-off time)
In MAIN time base mode, the control knob applies to the hold off
time setting, the HO-LED associated with the knob is dark, the hold
off time is set to minimum.
Switch on the LED by turning the control knob clockwise and extend
the hold off time until the maximum is reached. An approximate hold
off time value will be displayed in the readout (i.e.“HO= 25 %”).
The hold off time is automatically set to minimum (LED is dark), if
the MAIN time base setting is changed. The hold off time setting is
stored and deactivated if ALT (MAIN and DELAY) or DELAY time
base mode is selected.
DELAY TIME
In ALT (MAIN and DELAY) and DELAY time mode, the knob
controls the delay time setting.
Under the ALT time base mode, the delay time is visible on the main
trace, beginning at the trace start and ending at the start of the
window sector. An approximate delay time value will be displayed in
the readout (“DLY=0.125ms”).
If only select DELAY time base, the delay time can also be varied,
but there would be no window sector as the main trace is not visible.

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⎯28 ⎯
(31)TV-V/TV-H/TV-STD—Pushbutton for video sync signal selection.
In the TV trigger mode, each time when the pushbutton of
TV-V/TV-H/TV-STD is pressed, the video sync signal is displayed in
the sequence as follows:
TV-V—TV-H—TV-L(NTSC)—TV-L(PAL)—TV-L(SECAM)—TV-V
TV-V
Start the main trace at the beginning of a video signal field. SLOPE
polarity must match the composite sync polarity (i.e, “ ” for
negative sync) to obtain TV field triggering on the vertical sync
pulse.
TV-H
Start the main trace at the beginning of a video signal line. SLOPE
polarity must match the composite sync polarity to obtain TV line
triggering on the horizontal sync pulse.
The current setting is displayed in the readout under item “source,
video polarity, TV-H”.
TV-STD
Start the main trace at the beginning of a video signal line. SLOPE
polarity must match the composite sync polarity to obtain TV line
triggering on the horizontal sync pulse.
The current setting is displayed in the readout “SYSTEM, field, line
number”.
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⎯29 ⎯
(32)SLOPE ( )/TV SYNC POLA( )—Pushbutton for
the triggering slope or video polarity selection.
If in the AUTO or NML trigger mode, briefly pressing the pushbutton
to select the slope of the signal which is used for triggering the time
base generator. Each time when the pushbutton is briefly pressed, the
slope direction will switch from falling edge to rising edge, and vice
versa.
The current setting is displayed in the readout under item “source,
SLOPE, coupling”.
If in the TV trigger mode, briefly pressing the pushbutton to select the
video polarity, which will be displayed in the readout with a “ ”
symbol of positive video signal and a “ ” symbol of negative
video signal.
Measurement and Panel setting Control
The measurement section controls the on-screen readout and the cursor
measurements. For more information, please refer to page 9 “PANEL
INTRODUCTION” section for the instrument to store and recall the
panel setting.
33
AUTOSET
35
ON/OFF
CURSOR
MEAS'MT
FUNC
34
SETUPS RECALLSAVE
MEM 0 9

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⎯30 ⎯
(33)AUTOSET—
Pressing briefly the AUTOSET pushbutton to set the instrument to the
last time base mode of CH1, CH2 and DUAL.
At the same time, the attenuators VOLTS/DIV are automatically set at
a signal display height of approx. 3-6 div in mono channel mode or at
approx. 3 div height in DUAL mode for each channel.
The time range would change automatically and approx. 1.6 to 4
waveforms are displayed on the screen. For signal of 100Hz or in the
absence of a trigger, the time range is set to 5ms/div, and for the
signals of approx. 8MHz or more, it is set to 50ns/div. The time range
change automatically following the different incoming signal.
Proceed AUTOSET function to operate the instrument automatically
according to the following condition:
1. Set input coupling to AC.
2. Set internal triggering(CH1 or CH2).
3. Set deflection coefficients between 5V/div and 2mV/div calibrated
condition.
4. With main time base alternate and set off delay time base mode.
5. Automatic CH1 and CH2 horizontal position settings.
6. Trace and readout visible.
7. Set trigger level to zero, trigger mode to AUTO, and trigger
coupling to AC.
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⎯31 ⎯
(34) MEMO- 9 —SAVE/RECALL
The instrument contains 10 non-volatile memories, which can be used
by the operator to save instrument setting and to recall them. It relates
to all controls which are electronically selected.
Press or pushbutton to select the memory location. The
readout then indicates the letter “MEN” followed by a cipher between
0 and 9. Each time the pushbutton is briefly pressed the memory
location cipher increases until the number 9 is reached.
The pushbutton is similar but decreases the memory location
cipher until the number 0 is reached. Pressing and holding SAVE for
approx. 3 seconds to write the instrument settings in the memory and
indicate the associated readout information of “SAVED”.
To recall a front panel setup, select a memory location as described
above. Recall the settings by pressing and holding the RECALL
pushbutton for approx. 3 seconds, the readout then indicates the
associated readout information of “RECALLED”.
(35)MEAS’MT FUNC-CURSOR—
Pressing and holding the pushbutton to set Cursor measurement mode
on, then press briefly the pushbutton, the seven measurement functions
listed below will be selected in the sequence. Pressing and holding the
pushbutton again to set the Cursor measurement mode off.
The seven Cursor measurement functions:
△V : Voltage difference measurement.
△V% : Voltage difference percentage measurement
(5div=100% reference)
△VdB : Voltage gain measurement.
(5div=0dB reference,△VdB=20 log (△V div/5div)).

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⎯32 ⎯
△T : Time difference measurement.
△T% : Time difference percentage measurement.
(5div=100% reference).
1/△T : Frequency measurement.
△θ : Phase measurement.
(5div=360oreference).
OFF :
During the Cursor measurement going, the function of Auto-measurement
is still working at the same time automatically, and the screen is always
appeared “auto-measurement” at the right down corner. After the Cursor
measurement mode is set off, there are four measurement parameters
available for selection in the sequence as follows:
FREQ—PERIOD—±WIDTH—±DUTY—OFF
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⎯33 ⎯
Input connectors
The input section is where the input signals are commonly connected to
the oscilloscope.
(36)CH1—Input BNC socket
This BNC socket is the signal input for channel 1. In X-Y mode,
signals at this input are used for the Y or X deflection. The outer
(ground) connection is galvanically connected to the instrument
ground and consequently to the safety earth contact of the line/mains
plug.
(37)CH2—Input BNC socket
This BNC socket is the signal input for channel 2. In X-Y mode,
signals at this input are used for the X or Y deflection. The outer
(ground) connection is galvanically connected to the instrument
ground and consequently to the safety earth contact of the line/mains
plug.
(38)Ground socket—Banana Socket galvanically connected to safety
earth.
This socket can be used a reference potential connection for DC and
low frequency signal measurement purposes.

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⎯34 ⎯
(39)EXT—This BNC socket is the external trigger signal input.
In dual X-Y mode, signals at this input are used for the X deflection.
Pressing the TRIG. SOURCE (29) pushbutton until the information of
“EXT, slope, coupling” is shown up in the readout and the TRIG.
SOURCE “EXT or E/10” LED is lighted, switches the input on.
The outer (ground) connection is galvanically connected to the
instrument ground and consequently to the safety earth contact of the
line/mains plug.
The maximum input voltages of the instrument input terminals and probe
input terminals are listed in the section of 3-6. “Withstanding voltage of
Input terminals”. Do not apply voltage higher than the limit.
4-2.Rear Panel
The rear panel provides input power and additional signal connections.
TYPE AND RATED FUSE.
COVERS. REFER SERVICING TO
CONDUCTOR MUST BE CONNECTED TO GROUND.
FOR CONTINUED FIRE PROTECTION. REPLACE ONLY WITH SPECIFIED
NO OPERATOR SERVICEABLE COMPONENTS INSIDE. DO NOT REMOVE
TO AVOID ELECTRIC SHOCK THE POWER CORD PROTECTIVE GROUNDING
42
TRIGGER SIGNAL
OUTPUT
25mV/DIV
IEC1010 250V CAT
100
SELECTION
POWER MAX. 70 WATTS, 90VA
THE INSTRUMENT BEFORE REPLACING THE FUSE
ENSURE THE POWER IS REMOVED FROM
LINE VOLTAGE
40
230V
QUALIFIED PERSONNEL.
100V
120V
207~250V T 0.4A
250V
41
(50/60Hz)
RANGE
90~110V
108~132V T 1A
FUSE
250V
230
120
AC
WARNING
43
Z-AXIS
INPUT
30Vpk MAX.WINTO 50 CAT
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USER MANUAL
⎯35 ⎯
(40)Line voltage selector and input fuse holder—Select power source
and contain the primary power fuse
The fuse rating is shown in the section of 3-2 Checking the line
voltage.
(41)AC power input connector
Connect the AC power cord to the power supply of instrument, the
power cord protective-ground connection is connected to the exposed
metal part of the instrument. The power cord must be connected to a
proper grounded source for electrical-shock protection.
(42)TRIGGER SIGNAL Output—BNC socket
The signal selected by the TRIG. SOURCE (29) is available. This
output may be used to connect to a frequency counter or other
instrument.
(43)Z-Axis Input—BNC socket
Connect external signals to the Z-axis amplifier for intensity
modulating the CRT display. This terminal is DC-coupled. The
intensity is lowered by a positive signal, while it is increased by a
negative signal.