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8-1

Chapter 8

Amplitude Modulation

Title

Page

Introduction........................................................................................................ 8-2

Amplitude Modulation (Internal)....................................................................... 8-2

Modulation Frequency................................................................................... 8-2

Modulation Depth.......................................................................................... 8-2

Modulation Waveform .................................................................................. 8-3

VCA (External).................................................................................................. 8-3

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Summary of Contents for DDS Function Generator 271

Page 1: ...z DDS Function Generator Users Manual January 2005 2005 Fluke Corporation All rights reserved Printed in USA All product names are trademarks of their respective companies 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 2: ...ain return authorization information then send the product to that service center with a description of the difficulty postage and insurance prepaid FOB Destination Fluke assumes no risk for damage in transit Following warranty repair the product will be returned to Buyer transportation prepaid FOB Destination If Fluke determines that failure was caused by neglect misuse contamination alteration a...

Page 3: ...possibility of electric shock This instrument must be earthed Any interruption of the mains earth conductor inside or outside the instrument will make the instrument dangerous Intentional interruption is prohibited The protective action must not be negated by the use of an extension cord without a protective conductor When the instrument is connected to its supply terminals may be live and opening...

Page 4: ...ould be disposed of by a qualified recycler or hazardous materials handler Contact your authorized Fluke Service Center for recycling information Caution Do not wet the instrument when cleaning it and in particular use only a soft dry cloth to clean the LCD window The following symbols are used on the instrument and in this manual Caution refer to the accompanying documentation incorrect operation...

Page 5: ...erformance A d EN61000 4 4 1995 Fast Transient 1 kV peak ac line 0 5 kV peak signal lines and RS232 GPIB ports Performance A e EN61000 4 5 1995 Surge 0 5 kV line to line 1 kV line to ground Performance A f EN61000 4 6 1996 Conducted RF 3 V 80 AM at 1kHz ac line only signal connections 3 m not tested Performance A According to EN61326 the definitions of performance criteria are Performance criterio...

Page 6: ...ections are remade correctly before replacing the cover Always ensure all case screws are correctly refitted and tightened c In the event of part replacement becoming necessary only use components of an identical type Refer to the Service Manual 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 7: ...Multi level Square Wave 1 5 Arbitrary 1 5 Hop 1 5 Noise 1 5 Modulation Modes 1 5 Continuous 1 5 Trigger and burst 1 6 Gated 1 6 Sweep 1 6 Amplitude Modulation 1 6 Frequency Shift Keying FSK 1 6 Start Stop Phase 1 7 Trigger Generator 1 7 Outputs 1 7 Main Output 1 7 Aux Out 1 7 Trig Sweep Out 1 7 Inputs 1 8 Ext Trig 1 8 VCA In 1 8 Phase locking 1 8 Clock In Out 1 8 Sync Out 1 8 Interfaces 1 8 1 888 ...

Page 8: ...trast 4 3 Keyboard 4 3 Principles of Editing 4 4 5 Main Generator Operation 5 1 Introduction 5 2 Main Generator Parameters 5 2 Frequency 5 2 Output Level 5 3 Output Impedance 5 4 DC Offset 5 4 DC Output 5 5 Symmetry 5 5 Warning and Error Messages 5 6 The Auxiliary Output 5 7 Auxiliary Output Phase 5 8 Waveform Generation Options 5 9 Square Wave Generation 5 9 Filter 5 9 Auxiliary Output 5 10 Frequ...

Page 9: ...3 VCA External 8 3 9 FSK 9 1 Introduction 9 2 Frequency Setting 9 2 Trigger Source 9 2 10 Special Waveforms 10 1 Staircase 10 2 Arbitrary 10 3 Recalling Arbitrary Waveforms 10 3 Storing Arbitrary Waveforms 10 3 Noise 10 4 11 Hop 11 1 Introduction 11 2 Setting each Waveform Step 11 2 Defining the Sequence and Timing 11 2 Running the Sequence 11 3 Timing Considerations 11 3 Saving Hop Settings 11 4 ...

Page 10: ... 1 Remote Operation 16 2 Address and Baud Rate Selection 16 2 Remote Local Operation 16 2 RS232 Interface 16 3 Single Instrument RS232 Connections 16 3 Addressable RS232 Connections 16 3 RS232 Character Set 16 4 Addressable RS232 Interface Control Codes 16 4 Full List of Addressable RS232 Interface Control Codes 16 6 GPIB Interface 16 6 GPIB Subsets 16 6 GPIB IEEE Std 488 2 Error Handling 16 6 GPI...

Page 11: ...Miscellaneous Commands 16 16 Phase Locking Commands 16 16 Remote Command Summary 16 17 Appendices A AC Supply Voltage Settings A 1 B DDS Operation and Further Waveform Considerations B 1 C Application Information Notes C 1 D Warning and Error Messages D 1 E Factory System Defaults E 1 F Waveform Manager Plus F 1 G Front and Rear Panels G 1 ix 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 12: ...271 Users Manual x 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 13: ...are Wave 1 5 Arbitrary 1 5 Hop 1 5 Noise 1 5 Modulation Modes 1 5 Continuous 1 5 Trigger and burst 1 6 Gated 1 6 Sweep 1 6 Amplitude Modulation 1 6 Frequency Shift Keying FSK 1 6 Start Stop Phase 1 7 Trigger Generator 1 7 Outputs 1 7 Main Output 1 7 Aux Out 1 7 Trig Sweep Out 1 7 Inputs 1 8 Ext Trig 1 8 VCA In 1 8 Phase locking 1 8 Clock In Out 1 8 Sync Out 1 8 Interfaces 1 8 General 1 8 1 888 475...

Page 14: ...erfaces and then used in a similar way to the standard waveforms Up to five arbitrary waveforms of 1024 10 bit words can be stored in non volatile memory The maximum waveform clock frequency is 27 48 MHz This facility considerably expands the versatility of the instrument making it suitable for the generation of highly complex waveform patterns In addition numerous complex waveforms are pre define...

Page 15: ...andwidth 0 03 Hz to 700 kHz with adjustable amplitude and offset Multiple phase locked generators The signals from the reap panel CLOCK IN OUT socket and SYNC OUT sockets can be used to phase lock two or more generators Phase locked generators can be used to generate multi phase waveforms or locked waveforms of different frequencies Easy and convenient to use All of the main generator parameters a...

Page 16: ... harmonic spurious 65 dBc to 1 MHz 65 dBc 6 dB octave 1 MHz to 10 MHz Square Range 0 1 mHz to 10 MHz Resolution 0 1 mHz or 7 digits Symmetry control 1 to 99 0 1 resolution from 0 1 mHz to 30 kHz 20 to 80 0 1 resolution from 30 kHz to 10 MHz Accuracy 10 ppm for 1 year Output level 2 5 mV to 10 V p p into 50 Ω Rise and fall times 22 ns Aberrations 5 2 mV Triangle Range 0 1 mHz to 100 kHz Resolution ...

Page 17: ... programmed in the internal read only memory ROM Waveforms may also be downloaded via the RS232 or GPIB interfaces and stored in the internal non volatile random access memory RAM Frequency range 0 1 mHz to 10 MHz Waveform points are continuously output up to approximately 27 kHz above which they are sampled Output level 5 mV to 20 V p p into an open circuit Sampling frequency 27 48 MHz Number of ...

Page 18: ...rier waveforms All Sweep modes Linear or logarithmic single or continuous Sweep width From 0 1 mHz to 10 MHz in one range Phase continuous Start and stop frequency may be set independently Sweep time 10 ms to 999 s with 3 digit resolution Markers Two variable during sweep available at the rear panel socket Sweep trigger source The sweep may be free run or triggered manually front panel key by an e...

Page 19: ...offset plus signal peak is limited to 10 V from 50 Ω 600 Ω DC offset accuracy typically 3 10 mV unattenuated Resolution 3 digits for both amplitude and dc offset Pulse aberrations 5 2 mV Aux Out CMOS TTL levels with symmetry and frequency of main output The phase relationship between MAIN OUT and AUX OUT is determined by the start stop phase setting Trig Sweep Out The function of this output is au...

Page 20: ...nterfaces RS232 Variable Baud rate 9600 Baud maximum 9 pin D connector As well as operating in a conventional RS232 mode the interface can be operated in addressable mode whereby up to 32 instruments can be addressed from one RS232 port GPIB IEEE 488 Conforms with IEEE488 1 and IEEE488 2 General Display 20 character x 4 row alphanumeric LCD Data Entry Keyboard selection of mode waveform etc Value ...

Page 21: ...ction and Specifications Specifications 1 1 9 Pollution degree 2 Options 19 inch rack mounting kit Safety Complies with EN61010 1 EMC Complies with EN61326 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 22: ...271 Users Manual 1 10 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 23: ...2 1 Chapter 2 Installation Title Page Mains Operating Voltage 2 2 Fuse 2 2 Mains Lead 2 2 Mounting 2 2 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 24: ... earth conductor inside or outside the instrument will make the instrument dangerous Intentional interruption is prohibited The protective action must not be negated by the use of an extension cord without a protective conductor When a three core mains lead with bare ends is provided it should be connected as follows Brown Mains Live Blue Mains Neutral Green Yellow Mains Earth Mounting This instru...

Page 25: ...e Front Panel Connections 3 2 MAIN OUT 3 2 AUX OUT 3 2 EXT TRIG 3 2 Rear Panel Connections 3 2 CLOCK IN OUT 3 2 VCA IN 3 3 SYNC OUT 3 3 TRIG SWEEP OUT 3 3 RS232 3 4 GPIB IEEE 488 3 4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 26: ...IG is the external trigger input for trigger gate sweep FSK and hop operating modes It is also the input used to synchronize the generator as a slave to an external master generator Caution To avoid risk of damage to the instrument do not apply external voltages exceeding 10 V to this input Rear Panel Connections CLOCK IN OUT The function of the CLOCK IN OUT socket is set from the SYStem menu as f...

Page 27: ... the instrument do not apply external voltages to this output TRIG SWEEP OUT The function of this output is automatically determined by the generator s operating mode Except in sweep and hop modes the output is that of the internal trigger generator a fixed amplitude square wave whose frequency is set on the TRIG or GATE menus The rising edge of the trigger generator initiates trigger burst gate e...

Page 28: ...Pin 2 3 and 5 may be used as a conventional RS232 interface with XON XOFF handshaking Pins 7 8 and 9 are additionally used when the instrument is used in addressable RS232 mode Signal grounds are connected to instrument ground The RS232 address is set from the front panel using the REMOTE menu GPIB IEEE 488 The GPIB interface is an option It is not isolated the GPIB signal grounds are connected to...

Page 29: ...Chapter 4 General Operation Title Page Introduction 4 2 DDS Principles 4 2 Switching On 4 2 Display Contrast 4 3 Keyboard 4 3 Principles of Editing 4 4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 30: ... phase continuous frequency switching 6 Non standard waveforms such as multi level square waves are easily generated 7 Basic arbitrary waveform capability in the same instrument In addition being a digital technique it is easier to make every parameter programmable from the keyboard or remotely via RS232 or GPIB interfaces The fundamental limitation of the DDS technique is that as the generator fr...

Page 31: ...g a different key selects the function last selected with that key In this way it is therefore possible to select between for example sine square and triangle with single key presses or between positive pulses and negative pulses etc 2 SET keys permit direct selection of the four main generator parameters shown on the Main menu of the display ready for value entries from the NUMERIC UNIT keys 3 NU...

Page 32: ...pter 12 System Operations DIGIT keys operate in more than one mode When a numeric parameter value field is selected by the FIELD keys DIGIT keys step the edit cursor forwards or backwards through the digits of the field When the edit cursor is positioned in a parameter name for example FREQ pressing either digit key will step the parameter through each of the alternative forms in which a value may...

Page 33: ...xxx xxx Hz in which the most significant digit represents 100 Hz i e the 1 kHz increment would be lost If however the starting setting had been FREQ 1 000000 MHz i e a 100 Hz increment the display would have autoranged at 1 kHz to FREQ 900 0000 Hz and could then be decremented further right down to FREQ 000 0000 Hz without losing the 100 Hz increment Turning the control quickly will step numeric v...

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Page 35: ...put Impedance 5 4 DC Offset 5 4 DC Output 5 5 Symmetry 5 5 Warning and Error Messages 5 6 The Auxiliary Output 5 7 Auxiliary Output Phase 5 8 Waveform Generation Options 5 9 Square Wave Generation 5 9 Filter 5 9 Auxiliary Output 5 10 Frequency Stop 5 10 Trigger Sweep Output 5 10 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 36: ...R 100 0000us VhiZ 20 0 Vpp 50Ω DC 0 00mV 0 00mV SYM 50 0 50 0 When PER shows in the display instead of FREQ the frequency can be set in terms of a period enter the number and units ns µs ms or s in the same way as for frequency Note that the precision of a period entry is restricted to 6 digits 7 digits are displayed but the least significant digit is always zero The hardware is always programmed ...

Page 37: ...e parameter form selected the value is entered as a number followed by units for example 100 mV can be entered as 1 0 0 mV or 1 V etc The firmware acts intelligently in certain situations for example even if VhiZ or V is the selected parameter form entering a number followed by the dBm key will cause the number to be entered as dBm Similarly with dBm as the selected parameter form entering a numbe...

Page 38: ... not move into the DC OFFSET name because the dc offset has no alternative representation With the edit cursor in the numeric field turning the rotary control will increment or decrement the numeric value in steps determined by the edit cursor position within the field The DC OFFSET or FIELD keys move the cursor to the field and the DIGIT keys move it within the field Because dc offset can have ne...

Page 39: ...he dc offset plus signal peak is limited to 10 V to avoid waveform clipping a warning message will be displayed This is explained more fully in appendix D Warnings and Error Messages DC Output The dc offset control can be used to provide an adjustable dc output level if the waveform is off the recommended set up is as follows Select GATE edit mode and set the SOURCE to MAN REMOTE Exit edit mode an...

Page 40: ...LEVEL will be shown temporarily on the screen but the setting will be accepted in this case the actual attenuated offset will be shown in brackets to the right of the set value 2 With the output level set to 10 V p p increasing the dc offset beyond 5 V will cause the message DC OFFSET LEVEL MAY CAUSE CLIPPING The offset change will be accepted producing a clipped waveform and the user may then cho...

Page 41: ...followed by ERRor key the 2 numeric key The ERRor menu is shown below ERROR BEEP ON ERROR MESSAGE ON WARNING BEEP ON WARNING MESSAGE ON The flashing cursor can be moved through each of the four editable fields in turn using the FIELD keys The field can then be toggled between ON and OFF using the DIGIT keys or rotary control to create the desired setting If the new setting is required for future u...

Page 42: ...y rotary control Above 30 kHz the AUX OUT accompanying sine triangle square and pulse waveforms is automatically switched such that it is derived from the comparator driven by the DDS sine wave used to generate higher frequency MAIN OUT square waves and pulses The DDS Principles section gives further information This ensures a jitter free AUX OUT signal up to the maximum frequency of the generator...

Page 43: ...ency mode the square wave and pulse waves are generated digitally in this way precision square waves can be generated down to very low frequencies without the edge uncertainty that would be associated with conventional ramp and comparator techniques Above approximately 27 kHz clock frequency 27 487 MHz divided by 1024 the waveforms are sampled and the 1 clock 36ns uncertainty introduces edge jitte...

Page 44: ... is no automatic mode changeover if ramp staircase or arbitrary waveforms are selected high frequency mode can however be forced by setting AUX HIFRQ Note that there is some second order interaction between the square wave generation filter and auxiliary output settings which demands a little thought before deviations from the default conditions are applied For example if SQWAVE GEN and AUX option...

Page 45: ... sweep is operational or hop mode if HOP is on when SWEEP TGEN TRIG the TRIG SWEEP OUTput always outputs the internal trigger generator signal Note that except when using the internal trigger generator in trigger gate FSK or AM modes this signal is not synchronized with the main generator 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

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Page 47: ... Title Page Introduction 6 2 Connections for Sweep Operation 6 2 Setting Sweep Span and Markers 6 2 Setting Sweep Mode Ramp Time and Source 6 3 Frequency Stepping Resolution 6 4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 48: ...for information concerning the use of sweep with square waves Connections for Sweep Operation Sweeps are usually used with an oscilloscope or hard copy device to investigate the frequency response of a circuit The instrument s MAIN OUT is connected to the circuit input and the circuit output is connected to an oscilloscope or for slow sweeps a recorder To show the markers on the display instrument...

Page 49: ...be changed without interrupting the sweep A second marker is also displayed at the frequency set on the main menu i e at the frequency set for the generator in non sweep mode This offers the advantage of a marker adjustable from the same menu used to control amplitude offset etc The marker signal is output from the rear panel TRIG SWEEP OUT socket The output is low 0 V for the duration of the swee...

Page 50: ...eted before another trigger edge is recognized and a new sweep initiated The minimum trigger pulse width is 1 ms and the repetition rate should be greater than 110 of the sweep time plus 5 ms In MAN REMOTE mode a single sweep is initiated by each press of the MAN SYNC key or by each remote command If the MAN SYNC key is pressed during a sweep continuous or single sweep the sweep will be paused at ...

Page 51: ... generators usually have more restricted capabilities Note also that because the marker pulse duration from the rear panel TRIG SWEEP OUT socket is that of the nearest frequency step fast sweep rates with few steps will have wider marker pulses 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

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Page 53: ...le Page Introduction 7 2 Internal Trigger Generator 7 2 External Trigger Input 7 2 Triggered Burst 7 2 Trigger Source 7 3 Burst Count 7 3 Start Stop Phase 7 3 Gated Mode 7 4 Gate Source 7 4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 54: ... gate is therefore 0 01 ms to 100 s in step with trigger generator periods of 0 02 ms to 200 s External Trigger Input External trigger or gate signals are applied to the front panel EXT TRIG input which has a TTL level 1 5 V threshold In triggered burst mode the input is edge sensitive the rising edge of each external trigger initiates the specified burst In gated mode the input is level sensitive...

Page 55: ... currently displayed Burst Count The number of complete cycles in each burst following the trigger is set with the edit cursor in the BURST COUNT field Entries can be made directly from the keyboard or by rotary control the burst range is 1 to 1023 with a resolution of 1 cycle or 0 5 to 511 5 with a resolution of 0 5 cycles The first cycle starts and the last cycle stops at the phase set in the PH...

Page 56: ...d by pressing the EDIT key followed by the GATE key when gate edit is selected the lamp beside the GATE key flashes to show edit mode regardless of whether gate operation is currently selected to be on or off SOURCE EXT TGEN 1 00ms 1 000kHz Gate Source With the edit cursor in the SOURCE field of the gate edit menu the digit keys or rotary control can be used to select EXTernal MAN REMOTE or TGEN T...

Page 57: ...itude Modulation Title Page Introduction 8 2 Amplitude Modulation Internal 8 2 Modulation Frequency 8 2 Modulation Depth 8 2 Modulation Waveform 8 3 VCA External 8 3 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 58: ...M mode Modulation Frequency Select TGEN in the SOURCE field and move the cursor to the TGEN field to set the period of the internal trigger generator the modulation source for internal AM The internal trigger generator produces a square wave with a period that can be set from 0 02 ms 50 kHz to 200 s 0 005 Hz Period entries that cannot be exactly set are accepted and rounded up to the nearest avail...

Page 59: ... required output level and applying the modulation signal which may be ac coupled if required at the appropriate level to obtain the modulation depth required If the generator output level is changed the amplitude of the modulating signal will have to be changed to maintain the same modulation depth As with internal AM the maximum output setting of the generator at which clipping is avoided is red...

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Page 61: ...9 1 Chapter 9 FSK Title Page Introduction 9 2 Frequency Setting 9 2 Trigger Source 9 2 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 62: ...cursor in the SOURCE field of the FSK edit menu the DIGIT keys or rotary control can be used to select EXTernal MAN REMOTE or TGEN internal Trigger GENerator as the trigger source which controls the frequency shifting With the source set to EXTernal the frequency is switched at each rising edge of the signal applied to the EXT TRIG input The minimum pulse width that can be used with the EXT TRIG i...

Page 63: ...d elsewhere or one of the four letters G F A or T to indicate that the generator is currently set as the source on the GATE FSK AM or TRIG menus respectively in addition to the menu currently displayed 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

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Page 65: ...1 Chapter 10 Special Waveforms Title Page Staircase 10 2 Arbitrary 10 3 Recalling Arbitrary Waveforms 10 3 Storing Arbitrary Waveforms 10 3 Noise 10 4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 66: ... the selected step is rapidly dithered during editing by an amount equivalent to the least significant bit to help identify the correct step on an oscilloscope Move the cursor to the LENGTH field and use the keyboard or rotary control to enter the new length for that step in the appropriate units press ENTER to enter the value If the AUTO field has been left set at YES the default value the cursor...

Page 67: ... edit is selected the lamp beside the ARB key flashes to show edit mode regardless of whether ARB mode is currently selected to be on or off RECALL ARB NO 14 SINX X ENTER TO EXECUTE Recalling Arbitrary Waveforms The default arb edit menu is shown above With the edit cursor in the store number field each store can be stepped through in turn using the rotary control or direct keyboard entry Each sto...

Page 68: ... and AM modes Noise is selected from the noise menu accessed by pressing the EDIT key followed by NOISE on the numeric 4 key Noise is turned on and off with alternate presses of the DIGIT keys or by turning the rotary control When noise is on the lamp beside the last used function will be off and no other function including STAIR and ARB can be selected Having set noise on pressing ESCAPE will ret...

Page 69: ...e Page Introduction 11 2 Setting each Waveform Step 11 2 Defining the Sequence and Timing 11 2 Running the Sequence 11 3 Timing Considerations 11 3 Saving Hop Settings 11 4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 70: ...appropriate For further information see the Main Generator Parameters section in chapter 5 Main Generator Operations earlier in this manual The other parameters of the main menu symmetry and output impedance are set on that menu and are the same for every hop waveform The wave shape for each step is selected directly with the standard function keys or with the cursor in the edit field to the right...

Page 71: ... no editing is possible Exiting hop by pressing ESCAPE automatically sets HOP OFF and returns the generator to the setting used before hop was selected When hop is running the hop display will show the waveform parameters for each step which is manually stepped or has a duration greater than 500 ms the display will not track the changes of shorter steps or externally triggered steps Timing Conside...

Page 72: ... cannot be turned off in the usual way To recover from this situation hold the ESCAPE key down for approximately one second until hop mode is exited Saving Hop Settings The current hop setting is saved in non volatile memory at power down It is not part of the data saved by the STORE function see Storing and recalling set ups in chapter 12 System Operations and therefore only one complete hop sequ...

Page 73: ...RECALL menus To store a set up press the STORE key in the utilities section of the keyboard the display shows the following message SAVE TO STORE NO 1 ENTER TO EXECUTE Nine stores numbered 1 to 9 inclusive are available Select the store number using the rotary control or direct keyboard entry and press ENTER to execute the store function To recall a set up press the RECALL key the display shows th...

Page 74: ... keys to make the rotary control inactive Power Up Setting With the cursor in the POWER UP field the setting can be changed from POWER UP DEFAULTS the default setting to POWER UP POWER DOWN i e settings at power down are restored at power up or to POWER UP any of the settings stored in non volatile memories 1 to 9 POWER UP DEFAULTS restores the factory default settings described in the appendix CL...

Page 75: ...stem Settings12 12 3 press ENTER to execute pressing ESCAPE will return the setting to INPUT or OUTPUT Further details are given in chapter 13 Synchronizing Generators 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

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Page 77: ... Synchronizing Generators Title Page Introduction 13 2 Synchronizing principles 13 2 Connections for synchronization 13 2 Generator set ups 13 2 Synchronizing 13 3 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 78: ...imilarly the preferred synchronizing connection is from the rear panel SYNC OUT of the master directly to each of the EXT TRIG inputs of the slaves The alternative arrangement is to daisy chain from each SYNC OUT to the next generator s EXT TRIG in turn this does not give rise to any data integrity problems but cumulative hardware delays will degrade the phase shift accuracy Generator Set Ups Each...

Page 79: ...pter 12 System Operations The master is set to CLOCK BNC OUTPUT and all the slaves are set to CLOCK BNC PHASE LOCK Synchronizing Having made the connections and set up the generators as described in the preceding paragraphs synchronization is achieved by pressing the MAN SYNC key of each slave in turn Once synchronized only the clock connections need be maintained however any change to the set up ...

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Page 81: ...ntroduction 14 2 Equipment Required 14 2 Calibration Procedure 14 2 Setting the Password 14 2 Using the Password to Access Calibration or Change the Password 14 3 Calibration Routine 14 3 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 82: ... the counter to the AUX OUT socket The accuracy of the frequency meter will determine the accuracy of the generator s clock setting and should ideally be 1 ppm It may be quicker to use an oscilloscope for steps 05 and 15 see Calibration routine below Calibration Procedure The firmware provides for a four digit password in the range 0000 to 9999 to be used to access the calibration procedure If the...

Page 83: ...Routine The CALibration procedure proper is accessed by pressing the EDIT key followed by CAL the numeric 6 key At each step the display changes to prompt the user to adjust the rotary control or the FIELD or DIGIT keys until the reading on the specified instrument is at the value given Two keys and the rotary control are used to make adjustments the FIELD keys provide very coarse adjustment the D...

Page 84: ...r 1 768 V ac 5 mV CAL 14 20 dB intermediate attenuator Adjust for 0 707 V ac 1 mV CAL 15 AM square wave zero Adjust for minimum output CAL 16 AM square wave full scale Adjust for 10 V 10 mV CAL 17 AM sine wave full scale Adjust for 3 54 V ac 10 mV CAL 18 HF square wave symmetry 50 Adjust for 50 µs 0 1 µs CAL 19 HF square wave symmetry 75 Adjust for 75 µs 0 1 µs CAL 20 Clock calibrate Adjust for 10...

Page 85: ...2 Simple Main Generator Operation 15 2 Pulse Trains 15 2 Low Duty Cycle Pulse Trains 15 3 Multiple Pulses 15 4 Variable Transition Pulse Waveforms 15 4 Slew Limited Transitions 15 4 Band Limited Pulses 15 5 Pulses With Overshoot 15 5 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 86: ...cope to 1 V div the timebase to 200 µs div select dc coupling and observe the waveform Select the other waveforms in turn using the FUNCTION keys and observe the differences between SQUARE and the two PULSE options The oscilloscope trigger may need resetting when changing between wave shapes Select STAIR and ARBitrary wave shapes to view the default settings With SINE or TRIANGLE selected move the...

Page 87: ...esponds to the top of the rising edge of the pulse and starting at this phase will not give the desired result set the phase to 90 by moving the cursor to the PHASE field with the FIELD keys and enter 9 0 ENTER Whilst still in the trigger menu press TRIG again to turn Trigger mode on sha0012f emf A single cycle of the main generator i e a single pulse will now be output at the default frequency of...

Page 88: ...of different edge shapes Three examples are shown one with straight slew limited transitions and two with sinusoidal transitions where different start stop phase settings give quite different effects Slew Limited Transitions The edges of this slew rate limited pulse train are straight lines produced by half cycles of the main generator triangle wave The interval between the edges is again defined ...

Page 89: ...er parameters have been changed from the above example re enter them sha0015f emf Pulses With Overshoot Again the edges and overshoot peaks in this waveform are made up of sine wave segments The amount of overshoot depends on the starting phase angle which will be from 89 to about 30 The main generator amplitude determines the amplitude of the peaks the amplitude of the flat portions depends on th...

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Page 91: ...Event Status and Standard Event Status Enable Registers 16 8 Status Byte Register and Service Request Enable Register 16 8 Status Model 16 9 Power on Settings 16 9 Remote Commands 16 10 RS232 Remote Command Formats 16 10 GPIB Remote Command Formats 16 10 Command List 16 11 Function Selection 16 12 Main Generator Parameters 16 12 Sweep Parameters 16 12 Trigger and Gate 16 13 AM Parameters 16 13 FSK...

Page 92: ... address is selected with the edit cursor in the ADDRESS field using the DIGIT keys or rotary control Lastly the baud rate is selected with the edit cursor in the BAUD RATE field again using the DIGIT keys or rotary control When operating on the GPIB all device operations are performed through a single primary address no secondary addressing is used Note GPIB address 31 is not allowed by the IEEE ...

Page 93: ...32 interface with XON XOFF handshaking Pins 7 8 and 9 are used when the instrument is connected for addressable RS232 operation as described below Addressable RS232 Connections Using a simple cable assembly a daisy chain connection system between any number of instruments up to the maximum of 32 can be made as shown below INSTRUMENT 1 INSTRUMENT 2 INSTRUMENT 3 CONTROLLER TO NEXT INSTRUMENT sha0017...

Page 94: ...able RS232 interface control In this manual 20H etc means 20 in hexadecimal Addressable RS232 Interface Control Codes All instruments intended for use on the addressable RS232 bus use the following set of interface control codes Codes between 00H and 1FH which are not listed here as having a particular meaning are reserved for future use and will be ignored Mixing interface control codes inside in...

Page 95: ...nt 03H Universal Unaddress control code 04H Lock Non Addressable mode control code 18H Universal Device Clear Before a response can be read from an instrument it must be addressed to talk by sending the Talk Address control code 14H followed by a single character which has the lower 5 bits corresponding to the unique address of the required instrument as for the listen address control code above O...

Page 96: ...e Trigger DT1 Controller C0 Electrical Interface E2 GPIB IEEE Std 488 2 Error Handling The IEEE 488 2 UNTERMINATED error addressed to talk with nothing to say is handled as follows If the instrument is addressed to talk and the response formatter is inactive and the input queue is empty then the UNTERMINATED error is generated This will cause the Query Error bit to be set in the Standard Event Sta...

Page 97: ...so be configured so that the value of ist can be returned to the controller during a parallel poll operation The instrument is configured by the controller sending a Parallel Poll Configure command PPC followed by a Parallel Poll Enable command PPE The bits in the PPE command are shown below bit 7 x don t care bit 6 1 bit 5 1 bit 4 0 parallel poll enable bit 3 sense sense of the response bit 0 low...

Page 98: ...sed Bit 0 Operation Complete Set in response to the OPC command Status Byte Register and Service Request Enable Register These two registers are implemented as required by the IEEE standard 488 2 Any bits set in the Status Byte Register which correspond to bits set in the Service Request Enable Register will cause the RQS MSS bit to be set in the Status Byte Register thus generating a Service Requ...

Page 99: ...limited use in an RS232 environment The instrument will be in local state with the keyboard active The instrument parameters at power on are determined by the setting of the POWER UP field on the SYStem menu as described in the System Operations chapter If POWER UP POWER DOWN or POWER UP RECALL nn has been set and a defined state is required by the controller at start up then the command RST shoul...

Page 100: ...commands list Each response is terminated by 0DH carriage return CR followed by 0AH WHITE SPACE is defined as character codes 00H to 20H inclusive with the exception of those which are specified as addressable RS232 control codes WHITE SPACE is ignored except in command identifiers for example C LS is not equivalent to CLS The high bit of all characters is ignored Commands are not case sensitive G...

Page 101: ... the function groups Note that there are no dependent parameters coupled parameters overlapping commands expression program data elements or compound command program headers each command is completely executed before the next command is started All commands are sequential and the operation complete message is generated immediately after execution in all cases The following nomenclature is used rmt...

Page 102: ...t level to nrf pd V p p PDRMS nrf Set output level to nrf pd V rms DBM nrf Set output level to nrf dBm ZOUT nrf Set output impedance to nrf only 50 and 600 are legal DCOFFS nrf Set dc offset to nrf Volts SYMM nrf Set symmetry to nrf PHASE nrf Set phase to nrf degrees Sweep Parameters SWEEP cpd Set sweep mode to ON or OFF SWPBEGFRQ nrf Set sweep begin frequency to nrf Hz SWPBEGPER nrf Set sweep beg...

Page 103: ...selected first GPIB Group Execute Trigger command GET will perform the same function as TRG AM Parameters AM cpd Set AM mode to ON or OFF AMSRC cpd AM source to EXT or TGEN TGEN nrf Set trigger generator period to nrf seconds AMDEPTH nrf Set internal AM depth to nrf AMWAVE cpd Set internal AM wave to SINE or SQUARE FSK Parameters FSK cpd Set FSK mode to ON or OFF FSKFRQA nrf Set main generator fre...

Page 104: ... ARBRCL nrf Recall arbitrary waveform from store nrf ARB Query the selected arbitrary waveform responds SETARB 1024 nr1 rmt Waveform Generation Options SQRWAVGEN cpd Set square wave generation mode to AUTO HF or LF FILTER cpd Set filter mode to AUTO ON or OFF AUX cpd Set AUX output mode to AUTO HF or LF SWPTRGOUT cpd Set sweep tgen output bnc mode to AUTO SWEEP or TGEN Hop Commands HOP cpd nrf Set...

Page 105: ...strument are not affected by execution of the LRN command LRN character data Install data for a previous LRN command EER Query and clear execution error number register The response format is nr1 rmt QER Query and clear query error number register The response format is nr1 rmt CLS Clear status Clears the Standard Event Status Register Query Error Register and Execution Error Register This indirec...

Page 106: ...ted before the next is started this command takes no additional action Miscellaneous Commands IDN Returns the instrument identification The exact response is determined by the instrument configuration and is of the form NAME model 0 version rmt where NAME is the manufacturer s name MODEL defines the type of instrument and VERSION is the revision level of the software installed TST The generator ha...

Page 107: ...r default values SAV nrf Saves the complete instrument set up in the store number nrf SRE nrf Set the Service Request Enable Register to nrf SRE Returns the value of the Service Request Enable Register in nr1 numeric format STB Returns the value of the Status Byte Register in nr1 numeric format TRG Executes a trigger which will have the same effect as pressing the MAN SYNC key TST The generator ha...

Page 108: ...B to nrf Hz FSKPERA nrf Set main generator period to nrf seconds for completeness only FSKPERB nrf Set FSK period B to nrf seconds FSKSRC cpd Set FSK source to EXT MAN or TGEN GATE cpd Set gate mode to ON or OFF GATESRC cpd Set gate source to EXT MAN or TGEN HOP cpd nrf Set hop status to RUN or OFF with last step set to nrf LRN character data Install data from a previous LRN command NEGPUL Set neg...

Page 109: ... nrf seconds SWPLAW cpd Set sweep law to LOG or LIN SWPMKRFRQ nrf Set sweep marker frequency to nrf Hz SWPMKRPER nrf Set sweep marker period to nrf seconds SWPMODE cpd Set sweep mode to BTOE beginning to end or ETOB end to beginning SWPSRC cpd Set sweep source to CONT continuous EXT external or MAN manual SWPTIME nrf Set sweep time to nrf seconds SWPTRGOUT cpd Set sweep tgen output bnc mode to AUT...

Page 110: ...271 Users Manual 16 20 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 111: ... B DDS Operation and Further Waveform Considerations B 1 C Application Information Notes C 1 D Warning and Error Messages D 1 E Factory System Defaults E 1 F Waveform Manager Plus F 1 G Front and Rear Panels G 1 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 112: ...271 Users Manual 2 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 113: ...e sources 2 Remove the screws which retain the top cover and lift off the cover 3 Change the transformer connections as follows for 230V operation connect the live brown wire to pin 15 for 115V operation connect the live brown wire to pin 14 for 100V operation connect the live brown wire to pin 13 4 Refit the cover and the secure with the same screws 5 Change the fuse to one of the correct rating ...

Page 114: ...230V operation 250 mA T 250 V HRC for 100V or 115V operation 500 mA T 250 V HRC To replace the fuse disconnect the mains lead from the inlet socket and withdraw the fuse drawer below the socket pins Change the fuse and replace the drawer The use of makeshift fuses or the short circuiting of the fuse holder is prohibited A 2 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 115: ...hich reconstructs the waveform as a series of voltage steps Sine waves and triangle waves are subsequently filtered to smooth the steps in the DAC output The frequency of the output waveform is determined by the rate at which the RAM addresses are changed in a DDS system the address changes are generated as follows The RAM contains the amplitude values of all the individual points of 1 cycle 360 o...

Page 116: ... used to address the RAM At a waveform frequency of fCLK 1024 approximately 26 84 kHz the natural frequency the RAM address increments on every clock At all frequencies below this i e at smaller phase increments one or more addresses are output for more than one clock period because the phase increment is not big enough to step the address at every clock Similarly at waveform frequencies above the...

Page 117: ...o that all or none respectively of the waveforms will be filtered Interaction of Various Option Settings Important points to consider when setting the option menu fields to anything other than AUTO are as follows 1 The comparator which generates HF square waves and pulses for the MAIN OUT socket is driven by default by a filtered sine wave If the filter is set OFF the waveform driving the comparat...

Page 118: ... the filter 7 Setting square waves or pulses to LF mode at higher frequencies will also introduce an uncertainty of one clock edge at the AUX OUT socket even if this is still set to AUTO or HF because the comparator is now being driven by an LF mode waveform instead of the filtered sine wave Frequency Modes for Sweep and FSK For sweep and FSK operation the MAIN OUT and AUX OUT waveform modes are f...

Page 119: ...linear sweep will not function at all and a log sweep will reverse in direction The points at which these effects occur depend on the numerical values involved and cannot be defined precisely but the following serves as a guide if FINC 6 START 10 F stop frequency accuracy will be affected if FINC 7 START 10 F the sweep may not function at all In the above FSTART and FSTOP are the actual frequencie...

Page 120: ...m but as the frequency rises above 30 kHz some points get missed If either of the two points which define the edge of the square wave are missed then the edge will shift in time However due to the apparently random sampling phase which changes every cycle the points are not always missed in the same way so the edge appears to move on a cycle by cycle basis i e it jitters The total jitter from one ...

Page 121: ...e later of the two is reported first Warning and error messages are reported with a number on the display only the number is reported via the remote control interfaces The following is a complete list of messages as they appear on the screen In most cases they are self explanatory but where doubt may arise some further explanation is given Warning Messages 00 No errors or Warns have been reported ...

Page 122: ...in DC Offset exceeded 106 Max DC Offset exceeded 108 Symmetry value is illegal 112 Trigger generator period too big 113 Trigger generator period too small 115 Burst count value out of range 116 Phase angle value out of range 118 Trigger generator fixed by am sine 119 Mod depth value out of range 121 System ram error battery flat 126 Sweep time is too long 127 Sweep time is too short 128 No GPIB in...

Page 123: ...R or by the remote command RST Main menu parameters Frequency 10 kHz Output 20 V p p and output OFF Zout 50 Ω DC offset 0 V Symmetry 50 Trigger parameters Source EXT TGEN 1 ms Burst count 1 Phase 0 Gate parameters Source EXT TGEN 1 ms FSK parameters Freq A 10 kHz Freq B 10 MHz Source EXT TGEN 1 ms 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 124: ...ameters Default waveform from store 14 i e sin x x Sweep parameters Begin frequency 100 kHz End frequency 10 MHz Marker frequency 5 MHz Mode Beginning to end Law Log Ramp time 50 ms Trig Source Continuous Noise Noise OFF Hop parameters Hop OFF All parameters are unaffected by RECALL 0 or RST except Last Step which is set to 01 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 125: ... is very free and will allow most lists of numbers with or without intervening text to be read as waveform data points Waveform data may also be pasted to the clipboard for insertion into other programs Waveforms are displayed in fully scaleable windows and may be manipulated graphically Any number of waveforms in any of the supported types may be displayed simultaneously On line help is available...

Page 126: ... your hard drive A project may be placed anywhere in any directory folder and all waveform files for that project will be stored in a structure below that directory A project is identified by a user defined name Each project maintains its own library of expressions 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 127: ...Appendix G Front and Rear Panels Front panel sha0025f gif G 1 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 128: ...271 Users Manual Rear panel sha0027f gif G 2 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 129: ...3 4 rear panel 3 2 RS232 3 4 contrast display 4 3 control codes remote 16 5 controls 4 3 frequency 5 2 period 5 2 rotary 4 3 4 4 12 2 crystal master clock 14 2 cursor style 12 2 D daisy chain 13 2 16 3 dc offset 5 4 defaults E 1 digit keys 4 4 direct digital synthesis DDS 1 2 B 1 principles 4 2 display contrast 4 3 duty cycle low 15 3 E editing principles 4 4 error messages 5 6 D 1 errors handling...

Page 130: ...lation 1 5 8 2 VCA 8 3 mounting 2 2 multiple generators synchronization 13 2 N noise generation 10 4 O options waveform generation 5 9 output impedance 5 4 output level 5 3 outputs 1 7 auxiliary 5 10 trigger sweep 5 10 P password 14 2 phase auxiliary output 5 8 control signal 7 3 errors C 2 start stop 7 3 power on 16 2 16 9 power up display 4 2 power up settings 12 2 R ramp time 6 3 rear panel dra...

Page 131: ...weep menu 6 2 sweep mode 6 2 symmetry 5 5 sync out 3 3 synchronization 13 2 system settings 12 2 T trigger external 7 2 source 7 3 trigger generator 7 2 trigger sweep output 3 3 5 10 V VCA in 3 3 W warning messages D 1 warnings 5 6 Waveform Manager Plus F 1 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

Page 132: ...4 1 888 475 5235 info Fluke Direct com Fluke Direct com ...

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