Kenwood CV-1240 User manual

© PRINTED IN JAPAN
KENWOOD
525/60WAVEFORMMONITOR
CV-1240
625/50WAVEFORMMONITOR
CV-1245
INSTRUCTIONMANUAL
KENWOODCORPORATION

CONTENTS
1. FEATURES• • 3
2. SPECIFICATIONS 4
3. PRECAUTIONSFORUSE• 8
4. PANELEXPLANATION• 9
4-1 FRONT PANEL•••• 9
4-2 REARPANEL• 1 2
5. SCALE DESCRIPTION • • 1 4
6. OPERATINGPROCEDURES1 6
6-1PREPARATION• •••• • 1 6
6-2 DISPLAYING WAVEFORMS • 1 6
6-3 CHANGING THE SETTING OFRESPONSE• 1 7
6-4 CHANGING THE SETTING OF SWEEP •••••••• 1 8
6-5LINE SELECTOR1 9
6-6 MEASURING DIFFERENTIAL GAIN(DG)• 2 0
6-7 MEASURING K-FACTOR 2 0
6-8 RGB/YRGB PARADE DISPLAY •••• 2 1
7. MAINTENANCE AND ADJUSTMENT • 2 4
7- 1 MAINTENANCE 2 4
7-2 ADJUSTMENT • 2 5
This manual covers both CV-1240andCV-1245.Most descriptions are common to both,
with the information relating totheCV-1245 enclosed in brackets [ ]. Please read
the descriptions that apply to your model.
Aproduct of
KENWOODCORPORATION
17-5, 2-chome,Shibuya,Shibuya-ku,Tokyo150,Japan
2

1. FEATURES
The waveform monitor CV-1240 [1245], fitted witha 150mm-rectangular high-luminanceCRT
with internal graticule, isanosci1loscopeto monitor a video signal oftheM (B,G,H,
I, orD)systemTV.The CV-1240 [1245]hasthe following features:
#The scale forK-factor measurement isprovided.
#The1ine selector function enablestheuserto select one1inefor display, thereby
enabling theusertoobservetheVIT signal andVIR signal. The field canbeswitched
between 1 and2 in one-touch operation.
$The BLANKING OUTPUT terminalisprovidedtooutputsquare waves synchronouslywitha
selected 1ine.
$RGB parade display is possible. (YRGB is available asoption.)
#TheDC restorer isprovidedtomaintain back porchata constant level regardless of
the video signal type.
# Eight horizontal sweep modes available for selection are2H(2 1ines), 1H(1 1 ine),
1/is/div (enlarged 2-line display), 0.2/^s/div(enlarged1-1ine display), 2VMAG
(enlarged 2-field display), IVMAG(enlarged 1-field display), 2V(2 fields), and
IV (1 field).
#TheA input, B input, and external references ignal input(EXTREF)canbe
terminated at75 ohms by switch operationatthe rear ofthe CV-1240 [1245].
#5-turn controls are used forthe fine adjustmentofthe horizontal and vertical
posit ions.
#The scale rangefor vertical sensitivity isswitchedtothe calibrated IVor4Vful1
scale. Moreover, the vertical sensitivity canbeadjustedto0.25Vor less through4V
using a control.
#Theautofocus funct ionisprovided.
#The built-in calibrator, lVp-p± 1% and 100kHz ±100Hz,enablestheusertocheck
the sweep rangeaswellasamplitude.
#Two CV-1240s [1245s]canbeplacedonthe19-inch rack.
#Thesupplyvoltagecanbe selected from the rear ofthe CV-1240 [1245].
3

2. SPECIFICATIONS
CHARACTERISTICS
CV-1240
CV-1245
Number of scanning 1 ines
525 625
Field frequency
60Hz 50Hz
Subcarrier frequency
3. 58MHz
4. 43MHz
Appl icable system
M
B, G,H, I, D,K
Color system
NTSC, PAL
PAL, SECAM
CRT
Type
150mm rectangularwith internalgraticule
Effective screen
80mmx100mm
Acceleration voltage
12kV
Scale
140IRE full scale with
K factor 1.
0 ful1 scale with
K factor
Vert ica1axis
Inputterminal
Loop through for both A and B, BNC
Deflect ion
sensit ivity
IV full-scale
range ±2%
Deflect ion
sensit ivity
4V full-scale
range ±4X
Input
impedance
IV full-scale
range 15kQ±5X,
50pF or less
Input
impedance
4V fu11 -scale
range
60kQ±5%, 50pF or less
Frequency
response
(IV full-
scale
range)
FLAT
25Hz~5MHz±2X(50kHz REF)
Frequency
response
(IV full-
scale
range)
LUM
In accordance with IEEE STD 205, 1972
* Response (to "FLAT") : Within ±2%
Frequency
response
(IV full-
scale
range)
D* STEP
400kHz band pass fiIter to measure the 1inearity
of luminance component
Frequency
response
(IV full-
scale
range)
CHROMA
3.58MHz band pass fiIter
* Response (to "FLAT") :
Within ± 2%
4.43MHz band pass fiIter
* Response (to "FLAT") :
Within ± 2%
Frequency
response
(IV full-
scale
range)
DG
Theamplitude is about 3 to 5. 5 times that of"CHROMA"
4

CHARACTERISTICS
CV-1240
CV-1245
Verticalaxis
Transitional
response
IV full scale
"FLAT"
2T pulse
2T ber
Preshoot ±2%
Transitional
response
IV full scale
"FLAT"
2T pulse
2T ber
Overshoot ±2%
Transitional
response
IV full scale
"FLAT"
2T pulse
2T ber
Ringing
±2%
Transitional
response
IV full scale
"FLAT"
2T pulse
2T ber
Pulse & bar
rat io ±2%
Transitional
response
IV full scale
"FLAT"
2T pulse
2T ber
Tilt
±2%
Input sensitivity adjustment
(input voltage range at ful1
scale)
IV full scale : 0. 25Vor less toIV
4V ful1 scale : IVor less to4V
AMaximum inputvoltage
±5V(DC + ACpeak)
Horizontal axis
Sweep
2H
2-line display (KWdiv + 3%)
Sweep
1H 1-1
ine display (5/is/div ±3%)
Sweep
1 /is/div
10-magnification enlargement of 2-1ine display
(l/is/div±3X)
Sweep
0.2/Vdiv
25-magnification enlargement of 1-linedisplay
(0. 2/is/div±5X)
Sweep
2V
2-field display
Sweep
IV
1-field display
Sweep
2V MAG
25-magnification enlargement of 2-field display
Sweep
IV MAG
25-magnification enlargement of 1-field display
Sweep
Linearity
±3%
* The first and last divisions are excluded with all regular displays.
Synchronization
Internal reference amplitude Sync
level : 286mV± 6dB
Sync level : 300mV± 6dB
External referenceinput
terminal
BNC, loopthrough
External referenceinput
impedancje
15kQ, 50pF or less
AExternal reference maximum
inputvoltage
±8V(DC + ACpeak)
External reference amplitude Sync,
level : 143mVto5V
Sync, level : 150mVto5V
5

CHARACTERISTICS
CV-1240CV-1245
RGB parade display
Staircase input sensitivity
10V±15V9div
AMaximum inputvoltage
± 12V (DC + ACpeak)
Sweep
2H, 1H 1H
Sweep
2V, IV
IV
Sweep
Sweep trace length
About 3OXof sweep trace length
at composite displayx3
Composite-RGB select ion
Remote control by external or internal controlsignal
Remote controlsignal
10V (or-10V)to15V(or-15V)(5mA)
Signalinputterminal
9P MT socket
YRGB parade display-
Option
About 22% of sweep trace length
at composite displayx4
Video output
Output level
lVp-p±10# (75-ohm termination)
Output impedance
T5Q±10X
Frequencyresponse 25Hz~5MHz±5X(50kHz
REF)
Output terminal
BNC
Calibrator
Amplitude lVp-p±lX
Frequency 100kHz±100Hz
Blanking output
Line selected by1ine select
funct ion
OV
Other 1ines
-2V
Other than 1ine select mode
OV
Output terminal
BNC
Power source
Voltage
100/120/220+10X216V—250V50/60Hz
FUSE
100, 120V 1.0A
FUSE
220, 240V
0. 5A
Powerconsumpt ion
Approx. 40W
6

CHARACTERISTICS
CV-1240
CV-1245
Dimentionsandweight
() dimensionsinc1ude protrusion from basic out 1 inedimensions.
Width 215(215)mm
Height
132(147)mm
Depth 430(460)mm
Weight Approx.
7. 8kg
Operating temperatureandhumidity
Within specifications
10°C to 35°C, 85XRH or less
Ful1 operat ion
0°C to 50°C, 85XRH or less
Accessor ies
Instruct ion 1
BNCcap 8
AC power cord
1
9-pin MT plug
1
Replacement fuse
2
7

3. PRECAUTIONS FORUSE
1. Make sure ofthe supplyvoltagebefore use. A
combination fuseholder and vo1tage selector
is located tothe left ofanAC inlet terminal
at the rear ofthe CV-1240 [1245]. A value
pointed bythe• markabove theho lder is
thesupplyvoltage fortheCV-1240 [1245].
Us ing a wrongsupp lyvoltage will cause a
trouble. Before connect ing the power cord,
make sure ofthe supplyvoltage sett ing. To change the supplyvoltage, see Section
7 "Maintenance and Adjustment."
2. Avoid using theCV-1240 [12451 under the followingconditions:
CD Exposure to direct sunlight
(D High temperature and highhumidity
(D Exposure to mechanical vibration
(4) Near a strong magnetic source or impulse voltagesource
(DNear an explosive gas source or storage
3. A voltageapplied to inputterminalsshould not exceed their individual maximum
inputvoltages.
A andB inputterminals : ±5V(DC + ACpeak)
^ EXTREF inputterminal : ±8V (DC + ACpeak)
RGB inputterminal : ± 12V (DC + ACpeak)
Do not apply a voltage from outside to output terminals.
4. Donot increase luminance more than needed.
5. Donot leave a bright 1ine inthe spot state for longtime.
6. Donotputa thing onthe CV-1240 [1245] and avoidblocking the ventilation hole in
thecase.Otherwise, the internal temperature wil1 rise causing a trouble.
7. The CV-1240 [1245] has high-voltageparts inside; when the case istobe removed,
seeSection 7 "Maintenance and Adjustment."
8. GroundtheCV-1240 [1245] at the GND terminal for safety.
9. WhenthePOWER switch is tobe turned ONand OFF, putan interval of about 5 seconds
in between.
Turning the POWER switch ONandOFF continuously may cause malfunction.
10. Warmupthe CV-1240 [1245] for about 20 minutes for accurate measurement.
Thesupplyvoltage
is set to100V.
8

4. PANELEXPLANATION
4-1 FRONT PANEL
(D POWER
A power swi tch. Press ing the switchturns the power on, and another pressturns the
poweroff.
(D POWERLED
This LED interlocks with the POWER switch. Whenthe POWER switch is turned on, the
LED lights.
(D SCALE ILLUNI/PULL TRACE ROTA control
SCALEILLUM : Used to adjust the i1 luminance ofthe scale onthe screen. If the
i1 luminance ofthe scale istoo high,halation willresult at
photographing; adjust it by turning this knob.
TRACE ROTA : Used to correct the inclination of the horizontaltrace line caused with
the Knob pul led, for example, by earth magnet ism.
@ FOCUS/PULL ASTIG control
FOCUS : A focuscontrol.
ASTIG : Used to adjust the trace or spot astigmationwith the knob pulled. Optimize the
waveform condition by astigmation adjustment and focusing. Make adjustment so
that a round spot is observed.
9
Fig. 1-1 Front panel

(D INTEN control
Used to adjustthe luminous intensity of waveform.
®, ©,(D LINE SELECTOR switches
With push-button switch (D held down, a 1inespecified by digital rotaryswitch ® is
selected.
Push-button switch CD is a selectorswitchfor field 1 (odd) and field 2 (even).
With theswitchheld down, counting starts from field 2.
© RESPONSE switches
Used to select the type of frequency response from thefollowing five:
FLAT : Displayis made over the entire band.
LUM : A low pass filter conforming to IEEE STD205 1972isinserted.
D' STEP : A 400kHz band pass filter is used to measure the 1inearity ofthe luminance
component.
CHROMA: A 3.58 [4. 43] MHz band pass filter isinserted.
DG : A 3.58 [4.43] MHz band pass fi1ter is inserted. The amplitude is about
three to five times larger than CHROMA.
® REF switch
Used to select an internal or externalreference signal. Pressthe knob to select an
external reference signal.
© DC REST switch
With this knob set toON, the back porch is maintained ata constant level to prevent
adisplayed waveform from fluctuating upand down even when an input waveform changes.
(g) GAIN (switch)
Used to turn on (VARI) or off(CAL)thegaincontrolfunction.
@UNCALLED
When the GAIN switch © is pressed, this LED 1 ightsind i catingthat theun-
calibration stateisestablished.
@ ^•POSITION control
Used to adjustthehorizontalposition of waveform.
© ^POSITION control
Used to adjustthe vertical position of waveform.
® GAIN (control)
Againcontrol.Thiscontrolis effective only when the GAIN switch® isheld down.
When theIV ful1-scale range is used, a signal of 0.25V toIVin input level canbe
adjusted to full scale.
10

© SWEEP selector switch
Used to select the display modeofthe horizontal axis.
2H :
Two lines are displayed.
1H
One line is displayed.
l^s/div
The 2H display is enlarged at10 magnifications.
0. 2/is/div
The 1H display is enlarged at25 magnifications.
2V Two
fields are displayed.
IV
One field is displayed.
2V MAG
. The 2-field display is enlarged at25 magnifications.
IV MAG
: The 1-field display is enlarged at25 magnifications.
— Note
Whenthe 1ine selector is turned ON,the1H sweep is conducted atany setting of2H,
1H, 2V,andIV.
The 1H display is enlarged at10 magnifications when the display modeissetto
1/^s/div. The1H display is enlarged at25 magnifications when the display mode
is set to 0. 2/is/div, 2VMAG,orIVMAG.
In the RGB parade display, the1H sweep is conducted at either setting of1Hand2H,
and theIV sweep is conducted at either sett ing ofIVand2V.
© INPUT selectorswitch
Used to select theA orB input andto set sensitivity. With the knob set totheCAL
position, a calibration signal is displayed. "1" indicates theIV full-scale range, and
"4" the4V ful1-scale range.
11

4-2 REAR PANEL
® A INPUT terminals
Signalinputterminals ofthe loop through type. The input impedance is15 kiloohms
at theIV full scale, and60 kiloohms atthe4V ful1 scale.
Connect a cab 1 e of75ohmsin characterist ic impedance. Terminate oneoftwo
terminals at75ohms using the75-ohm switch ®,or connect itto equipment of75-ohm
fami ly.
(§) B INPUT terminals
SameasA INPUT. Select theA orB inputusing the INPUT knob © onthe frontpanel.
® EXTREF terminals
External referencesignalinputterminals. Two terminals are loop through type.
@VIDEOOUT terminal
A signalinput totheA orB terminalpasses the internal amplifier andis output from
this terminal. The amplitude is lVp-p per ful1 scale at75-ohm termination.
© BLANK OUT terminal
In the1ine select ingoperat ion, pulses are output from this terminal synchronously with
aselected1ine. The voltage is0V during the select ingoperation and—2Vin other
than the select ingoperation.
© 75-ohm switches
Used to terminate theA INPUT, B INPUT, andEXTREF terminals at75ohms.
Fig. 1-2 Rear panel
12

® RGB/YRGB INPUT terminal
A terminal for receiving a staircase signal anda remote controlsignalthat selects a
circuit intheCV-1240 [1245].
®J-
A grounding terminal.
@ Fuseholder and suppIy voltageselector
The fuse holder contains a 1. OA fuse foruseinthe100Vand120V commercial voltage
regions anda 0. 5A fuse foruseinthe220Vand240V commercial voltageregions. To
change the supply voltage, disconnect thepower cordfrom the outlet andsetthe voltage
selector toa desired supply voltage. (See Section 7 "Maintenance and Adjustment".)
® Power connector
AnACpower input connector.
13

5. SCALE DESCRIPTION
The CV-1240 usesa scale forthe NTSC system of525 lines and 60Hz. The CV-1245 usesa
scale forthePAL system of6251inesand 50Hz. Both scales are marked ontheinner
surface ofthescreenagainst parallax duringobservationand photographing. Adjustthe
illuminance ofthe scale for easy observationusingthe ILLUM control.
Figure 2-1isthe scale ofthe CV-1240. The left scale is marked inIREand ranges
from -50IREto+120IREatan interval of10IRE.140IRE corresponds to 1. 0V.
• There isa scale graduated atan interval of2 IRE siightly tothe left ofthecenterof
—40IRE line andthecenterof+100IRE1ine. These scales are used to measure the
amplitude ofa synchronizing signal andwhite level.
•Theblack level is marked inthe7.5 IRE position andthe15% whiteinthe77IRE
position bya dotted1ine.
•The rightscale is used to measure the modulation degree. +120IRE corresponds to
01and-40IRE1001
• Frames located siightly tothe right ofthecenterofthe+100IRE1ineare used to
measure the1ine time distortion. Thedotted-1ine frame indicates 21andthe solid-
line frame 41The2Tbarof18/^sinhalf-amplitude level is used for measurement.
•A dotted line anda solid1ineatthecenterofthe+100IRE1ineare used to measure
thepulse-to-bar ratio. They are weighted witha K-factorof2% and4% respectively.
14
Fig. 2-1Scaleofthe CV-1240

Fig. 2-2Scaleofthe CV-1245
Figure 2-2isthe scale ofthe CV-1245. The left scale ranges from -0.IVto+1.2Vatan
interval of0.IV.
• There isa scale graduated atan interval of0.02V siightly tothe left ofthecenterof
theOV1ineandthecenterofthe+1.OV1ine. These scales are used to measure the
amplitude ofa synchronizing signal andwhite level.
•The +0.15V and+0.45Vdotted1 inesindicate a burst ampl itude.
•The+0. 825V dotted line indicates the amplitude of15% white.
• Frames located s1ightly tothe left ofthecenterofthe+1.OV line are used to
measure the1ine time distortion. Thedotted-1ine frame indicates 2%, andthesolid-
line frame 41The2T trar of18/^sinhalf-amplitude level is used for measurement.
•A dotted1ineanda solid 1ineatthecenterofthe+1.OV1ineare used to measure
the pu1se-to-bar rat io. They are weighted withthe2% K-factorand4% K-factor
respectively.
For details ofthese scales,refer to CCIR STDVOL 5-1966.
15

6, OPERATING PROCEDURE
6-1 PREPARATION
1. Project theknobof POWER® (OFF).
2. Set INPUT® toA-l.
3. Project theknobof GAIN© (CAL).
4. Press theFLATknobof RESPONSE®.
5. Project theknobof REF© (INT).
6. Set SWEEP MODE© to1H.
7.Set ^POSITION© and ^•POSITION® tothe center position.
8. Project theknobofDC RESTORER© (OFF).
9. Set INTENSITY© tothe center position.
10. Hold theknobofFOCUS/PULL ASTIG© down.
11. Hold theknobofSCALEILLUM/PULLTRACE ROTA© down.
6-2DISPLAYING WAVEFORMS
After completing the preparation in 6-1, make sure ofthe supply voltage and insert the
power plug into an outlet.
1. Press POWER® to turn thepoweron. POWER LED® willlight.
2. When a bright 1ine appears onthe screen,adjust the luminous intensity ofwaveformby
turning INTENSITY©. Adjust the tracerotation,focus, and astigmation asneeded.
3. SetINPUT(DtoCAL.The following calibration signal will be displayed.
4.Supply a video signal toA INPUT®. Supply the signal to either oftwoBNCs.
Connect another BNCto equipment of 75-ohm family or turn the 75-ohm switch ON.
Calibration signal
16

6-3 CHANGING THE SETTING OF RESPONSE
5. Set INPUT © to A-l. The supplied video signal will be displayed. Adjust the
waveform position using ^POSITION© and^•POSITION®.
6.Ifmodulated staircase wavesareaddedtothe video signal, the resultant waveform
is as shown below.
7.If RESPONSE® issettoLUM,theluminance component of waveforms iswe11
represented as shown below.
8.If RESPONSE® issettoD'STEP,the following waveform appears. Thewaveformis
useful formeasuringthe 1inearity oftheluminance component.
9.If RESPONCE ® issetto CHROMA, the following waveform appears.
17

10. If RESPONSE® issetto DIFF GAIN, thewaveformabout three to five times as large as
CHROMA is obtained. Thewaveformis useful for measuring the differential gain.
6-4 CHANGING THE SETTING OF SWEEP
11. Set RESPONSE® backtoFLAT,andchangethe video signalsupplied toA INPUT® toa
pulse-and-bar signal. The following waveform will appear.
12. If SWEEP© issetto2H, lyus/div, or0. 2/is/div, the fol lowing waveformswi11be
observed.
13. If SWEEP© issetto2V,thewaveformofone frame is displayed. If SWEEP© issetto
IV, thewaveformofone field is displayed.
Thewaveforminthephotoisa video sweep signal.
18

14. If SWEEP© issetto2VMAG,the vertical blankingperiod canbewel observed.
15. IfDC REST© is turned ON,the pedestal level becomes constant,therebyenabling the
user to stably observe waveforms whose average picture level (APL)is fluctuating
and waveforms disturbed byhum.
16. Tousean external synchronizing signal, supply a composite sink signal or video
signal toEXT REF@ onthe rear panel, andset REF® toEXT.The terminals ofEXT
REF@ areofthe loopthroughtype:cableconnection is identical to that forthe
AINPUTandB INPUT terminals.
6-5 LINE SELECTOR
17. Set SWEEP© to1H,2H,IV,or2V.
The 1ine selector enables the user to easily observeVITS and VIRS.Pressswitch©
to turn the line selector ON. Select a field containing a signal tobe observedusing
switch©. The waveform corresponding toa 1 ine number indicated by switch®appears
onthe screen. Set switch® tothe line number ofa desired signal. Pulses are
output from the BLANK OUT terminalsynchronouslywith the selected 1 ine. Input the
pulses totheZ INPUT terminal ofthe vectorscope CV-1250/1255for vector display of
the 1 ine. Theuseofthe1ine selector causesluminance to drop below the regular
display.
19

6-6 MEASURING DIFFERENTIAL GAIN (DG)
18. Turn LINE SELECTOR© off, and set SWEEP© to1Hor2H. Input modulated staircase
waves toa device tobe measured, and input the output from the device toA INPUT®.
Adjust the level to match the scale using GAIN© and GAIN®. The photo isan
example of waveform with a differential gain of101
6-7 MEASURINGK-FACTOR
19. Set RESPONSE© to FLAT and SWEEP© to2H.
20. Usea test signalincluding 2T pulses andbar signal.
21. To measure the 1 ine time distort ion and pulse-to-barrat io, match the pedestal level
of the signalwith the pedestal1ine(01RE10.3) ofthe scale. Match the rising edge
of the composite test signal's bar with an upward arrow located siightly tothe
right ofthe scale center.Adjust the signal amplitude between the base 1ine and
thewhite bar center to 100IRE using the GAIN control ©. Check that the falling edge
of thebar is ona downward arrow.
22. To obtain the K-factor ofa line time distortion, measure the maximum deviation of
barswithin a frame. The first and last l^s divisions areignored andnot included in
the frame because of potential ringing, overshoot, or undershoot. The outer solid-
line frame indicates the4% K-factor, andthe innerdotted-1ine frame the2% K-factor.
(For a signalhaving a barof over 18y"sin half-amp 1 itude level, measure a
deviation within the frame when a rising edge is matched with an upward arrow anda
deviation within the frame when a falling edge is matched with a downward arrow.)
23. Measure the pulse/barK-factor(Kpb)using solid lines and dotted-lines atthe scale
center. These solid lines and dotted-linesare graduated according tothe following
formulas:
1 . 1
(1-4K)
an
(1 + 4K)
K = 0.02 ... 2% K-factor (dashed line)
K - 0.04 ... 4% K-factor (solid line)
20