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39

Subject to change without notice

26.1.1

 X POS 

If the pushbutton is dark the HORIZONTAL knob 

27

 functions as 

X position control, i.e. it moves the signal display horizontally. 
The position control is especially useful when the magnifier 
(MAG. x 10 

29

) is switched on. The magnifier will magnify the 

display 10 times around the screen centre. Using the POS 
control, the portion of the signal to be studied can be shifted 
on the screen. 

26.1.2

 DELAY 

In order to change the function of the HORIZONTAL knob 

27

 to 

”Delay“ proceed as follows: 
Press the HOR VAR pushbutton 

30

 

which will present the ”Time 

base“ menu, select ”Search“ or ”B only“, then the function of the 
knob will be changed if the pushbutton is depressed. It will light 
up to show that the knob is now the delay time control. 

In ”Search“ mode both traces (time base A and B) alternate. 
Unlike the former time base ”A only“ mode, a sector with hig-
her intensity is visible on the A trace. This sector can be moved 
continuously by the delay time control. The time between the 
A trace start and the beginning of the intensified sector is the 
delay time. This information is also displayed in the readout (”Dt: 
…“) and is an aid to find the position of the intensified sector 
which may be very small. If time base ”B only“ is chosen the 
intensified sector is no longer visible, but the DELAY function 
still can be used. 
Without activated ”B Trigger“ function, the B time base will be 
started after the A time base delay time ”elapsed“. 

26.2 Digital mode 

The pushbutton will indicate the actual function in accordance 
with the front panel lettering:
dark   =  Post- and Pre Trigger control (moves the trigger point
  

 

in horizontal direction).

green  =  Delay time control for horizontal Zoom position= 

shift.

26.2.1

 X-POS delay

If the pushbutton is dark the HORIZONTAL 

27

 knob functions as X 

position control of the trigger time, i.e. it moves the trigger point 
symbol horizontally. This allows display of signal portions before 
and after the trigger, called Pre Trigger and Post Trigger. If the 
trigger point symbol is located on the screen centre the readout 
will show ”Tt:0s“, hence the trigger time indication is always re-
ferred to the screen centre. Values with a positive sign are Post 
Trigger times, those with a negative sign Pre Trigger times. 
If the X POS DELAY pushbutton is depressed the ”Hor.Knob“ 
menu will be called, it contains the following options: 

1

st

  Centre: Pressing the function pushbutton ”Center“ will set 

the trigger time to the screen centre ”Tt:0s“ which is the 
standard setting. 

2

nd

 Coarse On Off: changes the speed of the HORIZONTAL 

knob. 

26.2.2

 DELAY Zoom Pos

This pushbutton will be illuminated if the ”Time base“ menu was 
called with the HOR VAR 

30

 pushbutton and ”Search“ selected. The 

HORIZONTAL 

27

 knob can then be used to select a portion of the 

time base display which is to be displayed expanded in time. 

In ”Search“ mode the normal and the expanded displays are 
displayed simultaneously, if neither reference nor mathematic 
signals are displayed. The expanded portion of the signal will 
be shown on the normal display as an intensified sector. The 
length of this sector is dependent upon the setting of the 2nd 
”Z“, time base which is shown in the readout as ”Z...“ and is 
equal to the run time of the Z time base.  

27

 HORIZONTAL 

(knob)

 

The various functions of this knob depend on the operating mode 
and are described under X POS DELAY pushbutton 

26

.

FFT (digital mode only)

As in Yt mode this knob moves the display in X direction. This 
changes the frequency range and consequently the center 
frequency setting displayed in the readout.

28

 TIME

/

DIV.–SCALE–VAR 

(knob)

 

This knob is normally used as the time base speed selector, but 
has also other functions dependent on the operating mode. In 
XY mode this control is disabled. 

28.1 Analog mode 

28.1.1

 Time base A time/cm selection 

This function is active if in the ”Time base“ menu (HOR VAR 
pushbutton 

30

 

) ”A only“ is selected and the option ”A variable 

On Off“ is set to Off. 
Turning the knob CCW will decrease, turning it CW will increa-
se the time base speed. The time base speed may be chosen 
between 500 ms/cm... 20 ns/cm in a 1-2-5 sequence and will be 
calibrated. The readout will show the setting (e.g. ”A:20ns“). 

28.1.2

 Time base B time/cm selection 

This function is active if in the ”Time base“ menu HOR VAR 
pushbutton 

30

) ”Search“ or ”B only“ was selected and the option 

”B variable On Off“ was set to Off. Turning the control CCW will 
decrease, turning it CW will increase the time base speed. The 
speed can be selected between 20 ms/cm.. 20 ns/cm in a 1-2-5 
sequence and will be calibrated. The readout will show the speed 
(e.g. ”B:20ns“). The time base B allows display of portions of 
the time base A display on an expanded time base scale. This 
implies that the speed of TB B must always be greater than that 
of TB A. Therefore with the exception of 20 ns/cm TB B can not 
be set to the same speed as TB A or slower. 

Further information is available in the section ”Time base B (2

nd

 

time base) / Delay / Triggering“ (Analog mode) in the chapter 
”Triggering and time bases“. 

28.1.3

 Variable 

The TIME/DIV–SCALE–VAR control may also be used to change 
the time base speed continuously but uncalibrated. VAR will 
light up on top of the HOR  VAR pushbutton 

30

 in order to warn 

that the time base is uncalibrated and the knob has now that 
function.

In order to arrive at that function press HOR VAR pushbutton 

30

 which calls the ”Time base“ menu. Depending whether time 

base A or B is selected either ”A variable On Off“ or ”B variable 
On Off“ will be shown. The function pushbutton can then be 
used to select On/Off. 

In order to point out that the time base is now uncalibrated 
the readout will replace ”:“ by ”

>

“ preceding the time/cm. (e.g. 

”A

>

500ns“ and ”B

>

200ns“). Also the results of cursor time/pe-

riod measurements will be marked that way. 

28.2 Yt digital mode 

28.2.1

 ZOOM OFF 

(A time base time/cm selection) 
Select the menu ”Zoom“ by pressing HOR VAR pushbutton 

30

 

and then ”Off“ in order to set the function of the knob TIME/DIV–
SCALE–VAR to time base A speed as in analog mode. If ”Zoom 

          C o n t r o l s  a n d  R e a d o u t

Содержание CombiScope HM2008

Страница 1: ...200 MHz Mixed Signal CombiScope HM2008 Manual English...

Страница 2: ...irective des equipements basse tension 73 23 CEE amend e par 93 68 CEE Angewendete harmonisierte Normen Harmonized standards applied Normes harmonis es utilis es Sicherheit Safety S curit EN 61010 1 2...

Страница 3: ...ajous gures 14 Measurement of phase differences in dual channel Yt mode 14 Measurement of amplitude modulation 15 Triggering and time base 15 Automatic peak triggering MODE menu 15 Normal trigger mode...

Страница 4: ...t voltage Time Base 2ns div 50s div Acquisition modes Single Refresh Average Envelope Roll Peak Detect Front USB Stick Connector for Screenshots USB RS 232 optional IEEE 488 or Ethernet USB Signal dis...

Страница 5: ...range 0 250 MHz Coupling DC Level control range 10 10 div Horizontal Deflection Analog Time Base Operating modes A ALT alternating A B B Time base A 20 ns div 0 5 s div 1 2 5 sequence Time base B 20 n...

Страница 6: ...rent positions A and B carrying C horizontal operating D and E operating at different angles F handle removal T shipping handle unlocked A A B B C C D D E E T F PUkT PUkT PUk PUk PUk PUk PUk PUk PUkT...

Страница 7: ...may be 20 C to 70 C Please note that after exposure to such temperatures or in case of condensation proper time must be allowed until the instrument has reached the permissible temperature resp until...

Страница 8: ...V SCALE VAR knob 34 Channel 1 Y de ection coef cient Y variabel and Y scaling setting 17 VOLTS DIV SCALE VAR knob 34 Channel 2 Y de ection coef cient Y variabel and Y scaling setting 18 AUTO MEASURE p...

Страница 9: ...selection of PROBE ADJ square wave signal hard ware and software information and details about interface rear side and USB Stick ash drive connector 42 COMPONENT TESTER 2 sockets with 4 mm 47 Connecto...

Страница 10: ...st be taken however when charging and discharging a large capacitor DC coupling is preferable with all signals of varying duty cycle otherwise the display will move up and down depending on the duty c...

Страница 11: ...ursors may be used for measurement Measurement Adjust the rising portion of the signal to 5 cm Position the rising portion symmetrically to the graticule centre line using both Y and X positioning con...

Страница 12: ...e ground connections of probes are especially critical they should be as short as possible and of large size STOP If a probe is to be connected to a BNC connector use a probe tip to BNC adapter If rip...

Страница 13: ...mind The oscillosco pe vertical ampli ers are two separate ampli ers and do not constitute a true difference ampli er with as well a high CM rejection as a high permissible CM range Therefore please o...

Страница 14: ...and Y signals af ter reading a and b off the screen is possible using the following formulas and a pocket calculator with trigonometric functions This calculation is independent of the signal amplitud...

Страница 15: ...ime base variable or external triggering Reading a and b off the screen the modulation degree will result a b a b m bzw m 100 a b a b a UT 1 m and b UT 1 m When measuring the modulation degree the amp...

Страница 16: ...ange the slope Positive or negative slope may be selected in auto or normal trigger modes Also a setting both may be selected which will cause a trigger irrespective of the polarity of the next slope...

Страница 17: ...Insert a 100 resistor between the center conductor and the BNC connector If possible the coil should be shielded without creating a shorted winding Alternate trigger This mode is selected with SOURCE...

Страница 18: ...time for most of the time the digital will not see the signal Also in analog mode the signal itself will be seen on the screen in real time whereas a digital can only show a reconstruction of the sig...

Страница 19: ...er COMPONENT PROBE 40 and COMPONENT TESTER 41 The scope has a built in component tester The test object is connected with 4 mm banana plugs In this mode the Y ampli ers and the time base are turned of...

Страница 20: ...pend strongly on the kind of FET With depletion type MOSFETs and all JFETs the channel will conduct if prior to testing the gate was connected to the source The Rdson will be shown As this can be very...

Страница 21: ...ependent single event recording with Yt display Single Readout display sgl 4 Trigger independent continuous recording menu VERT XY with XY display XY Readout display XY 5 XY display of previously in Y...

Страница 22: ...value of the sampling interval 1 sampling interval sampling rate 3 The signal frequency value is related to the highest sine wave signal frequency that can be captured with 10 samples per period realt...

Страница 23: ...s shows a straight line in the position of the positive peak value and consequently suggest a positive DC voltage An alias may also take the form of a signal of much lower frequency beat frequency bet...

Страница 24: ...rogram for USB connection test RS 232 The RS 232 interface has the usual 9 pole SubD connector Via this bidirectional interface the scope can be controlled remo tely or its settings may be transferred...

Страница 25: ...ilable submenus In some modes various pushbuttons or INTENS operations are meaningless and will hence not cause a menu display STOP Please note If a menu is shown some other information dis played in...

Страница 26: ...to leave the menu Thereafter only the signal display is activated and the FOCUS TRACE MENU pushbutton will blink as long as the readout is off Pressing the ashing pushbutton calls the Int Knob menu wh...

Страница 27: ...hannel mode Yt in the section First time operation and pre settings One period of a sine wave is equal to 2 hence the dis tance between the two long CURSOR lines must be set to one period If the dista...

Страница 28: ...will be lost after turn off Mathematics offers 7 1 Equations set Using the INTENS knob 5 sets of formulas can be selected for editing This way 5 user de ned formula sets may be created Each set of fo...

Страница 29: ...he display of the former The display will remain on screen until the next acquisition is started by the trigger and causes a new recording This mode is available over the full time base range 50 s cm...

Страница 30: ...size is 0 25 s between the samples at a time base setting of 50 s cm The advantage of Peak Detect is that signals are sampled with the highest possible sampling rate to reduce the gap size so that eve...

Страница 31: ...RE1 RE1 the signal will be displayed twice on the same spot Associated settings Pressing this function key causes the oscilloscope to take over the settings parameter stored when the signal was store...

Страница 32: ...s will remain The digital modes Roll Envelope or Average will be changed to refresh mode AUTOSET will further set the intensity to an average value if it was set too low If a menu was opened it will b...

Страница 33: ...control if Yt mode time base mode is present and the CH1 2 CURSOR MA REF ZOOM pushbutton 15 is not lit 14 1 2 Y Position of the FFT display only in digital mode measured with channel 2 Position 2 allo...

Страница 34: ...he CH1 menu the de ection coef cient becomes calibrated the CH1 VAR pushbutton 31 does not light any longer and the VOLTS DIV SCALE VAR knob 16 returns to 1 2 5 sequence 16 3 Scaling the FFT display d...

Страница 35: ...at V rms the range is from 5mV cm to 20V cm also switched in 1 2 5 sequence Please note that in contrast to Yt and XY mode signal display no peak to peak values but rms values are displayed 18 AUTO ME...

Страница 36: ...me base set B trigger to positive or negative slope Thereafter the LEVEL A B control will control the time base B trigger a second trigger point symbol will be shown and marked with B 19 2 FFT mode Th...

Страница 37: ...mpli er bandwidth and consequently less trigger signal noise Readout Tr Source Slope AC or DC NR 21 1 2 Slope SLOPE determines whether the rising or falling portion of a signal shall trigger the level...

Страница 38: ...5 External In this mode the trigger signal comes from the AUXILIARY INPUT TRIG EXT 38 Readout Tr ext Slope Filter 22 1 6 AC Line The trigger signal is taken from the line mains supply which feeds the...

Страница 39: ...ither reference nor mathematic signals are displayed The expanded portion of the signal will be shown on the normal display as an intensi ed sector The length of this sector is dependent upon the sett...

Страница 40: ...ave form become digitised and at least show spectrum displays spectra that do not exist in reality If the sampling rate is too low the readout displays ALS if the signal is too high overrange will be...

Страница 41: ...nly B The TIME DIV SCA LE VAR knob then only affects time base B By aid of the MAG x10 pushbutton 29 the signal display can be expanded 10 fold reducing the time de ection coef cient by factor 10 30 1...

Страница 42: ...sensitivity setting is for AC and is for DC 31 1 1 DC coupling The signal will be directly coupled from the BNC connector via the attenuator to the vertical ampli er The input resistance is 1 M in all...

Страница 43: ...DUAL trace alt chop In dual trace mode both channels are turned on and the para meters of both are shown in the readout Between the sensi tivity indications there is an indication whether alternate al...

Страница 44: ...It is recommended rst to look at the signals in DUAL mode and to set the sampling rate such that at least one signal period will be displayed Then XY should be selected In XY digital mode both channe...

Страница 45: ...he VOLTS DIV SCALE VAR knob 17 returns to 1 2 5 sequence switching and CH2 to calibrated condition 34 INPUT CH1 BNC connector This is the CH1 signal input connector In Yt mode it is a Y input in XY mo...

Страница 46: ...accuracy of the FFT calculations in the following averageing process Numbers between 2 and 512 can be chosen by aid of the INTENS 2 knob which are displayed by the readout e g avg 256 The accuracy in...

Страница 47: ...ive is connected with the USB Stick connector 43 41 4 1 USB Stick Save Front Panel current oscilloscope parameters The current parameters are saved on the USB ash drive by pressing the function key Sa...

Страница 48: ...D 63533 Mainhausen A Rohde Schwarz Company Tel 49 0 61 82 800 0 DQS Certi cation DIN EN ISO 9001 2000 Fax 49 0 61 82 800 100 Reg Nr 071040 QM sales hameg com w w w h a m e g c o m 41 2008 00E1 authori...

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