INSTRUCTION MANUAL 4080 Series Function and Arbitrary/Function Generators Model 4084AWG, 4086AWG, 4084, 4085, 4086, 4087 4080 series Function & Arbitrary/Function Generators -Instruction Manual Safety Summary The following safety precautions apply to both operating and maintenance personnel and must be observed during all phases of operation, service, and repair of this instrument. Before applying power, follow the installation instructions and become familiar with the operating instructions for this instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design, manufacture, and intended use of the instrument. B&K Precision Corporation assumes no liability for a customer's failure to comply with these requirements. This is a Safety Class I instrument. GROUND THE INSTRUMENT To minimize shock hazard, the instrument chassis and cabinet must be connected to an electrical ground. This instrument is grounded through the ground conductor of the supplied, three-conductor ac power cable. The power cable must be plugged into an approved three-conductor electrical outlet. Do not alter the ground connection. Without the protective ground connection, all accessible conductive parts (including control knobs) can render an electric shock. The power jack and mating plug of the power cable meet IEC safety standards. DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE Do not operate the instrument in the presence of flammable gases or fumes. Operation of any electrical instrument in such an environment constitutes a definite safety hazard. KEEP AWAY FROM LIVE CIRCUITS Instrument covers must not be removed by operating personnel. Component replacement and internal adjustments must be made by qualified maintenance personnel. Disconnect the power cord before removing the instrument covers and replacing components. Under certain conditions, even with the power cable removed, dangerous voltages may exist. To avoid injuries, always disconnect power and discharge circuits before touching them. WARNINGS AND CAUTIONS WARNING and CAUTION statements denote a hazard. Follow all instructions contained in these statements. A WARNING statement calls attention to an operating procedure, practice, or condition, which, if not followed correctly, could result in injury or death to personnel. A CAUTION statement calls attention to an operating procedure, practice, or condition, which, if not followed correctly, could result in damage to or destruction of part or all of the product. WARNING: Do not alter the ground connection. Without the protective ground connection, all accessible conductive parts (including control knobs) can render an electric shock. The power jack and mating plug of the power cable meet IEC safety standards. WARNING: To avoid electrical shock hazard, disconnect power cord before removing covers. Refer servicing to qualified personnel. CAUTION: Before connecting the line cord to the AC mains, check the rear panel AC line voltage indicator. Applying a line voltage other than the indicated voltage can destroy the AC line fuses. For continued fire protection, replace fuses only with those of the specified voltage and current ratings. 2 4080 series Function & Arbitrary/Function Generators -Instruction Manual Table of Contents 1. PRODUCT INTRODUCTION ................................................................................................5 1.1 Description .......................................................................................................................5 1.2 Key features ......................................................................................................................5 2. SPECIFICATIONS ..................................................................................................................6 2.1 Function Generator ...........................................................................................................6 2.2 Universal Counter .............................................................................................................9 2.3 General .............................................................................................................................10 3. PANEL DESCRIPTION ..........................................................................................................11 3.1 Front Panel........................................................................................................................11 3.1.1 Overview of Keys ....................................................................................................11 3.1.2 Display Annunciators ...............................................................................................12 3.1.3 Description of front panel keys ................................................................................13 3.1.3 Description of menu parameters ..............................................................................14 3.2 Rear Panel.........................................................................................................................17 4. OPERATING INSTRUCTIONS ..............................................................................................18 4.1 Installation ........................................................................................................................18 4.2 Main operating modes ......................................................................................................18 4.3 Waveform Selection..........................................................................................................19 4.4 Data entry .........................................................................................................................20 4.5 Output Configuration........................................................................................................21 4.5.1 Set Frequency and Period.........................................................................................21 4.5.2 Set Amplitude ...........................................................................................................21 4.5.3 Set DC Offset Voltage ..............................................................................................22 4.5.4 Adjust duty cycle ......................................................................................................22 4.5.5 TTL Signal ...............................................................................................................23 4.5.6 Signal Store and Recall ............................................................................................23 4.6 Set Modulation and Sweep Parameters ............................................................................24 4.6.1. Sweep mode ............................................................................................................24 4.6.2 FM modulation .........................................................................................................26 4.6.3 AM modulation ........................................................................................................27 4.6.4 Burst modulation ......................................................................................................28 4.6.5 FSK modulation .......................................................................................................30 4.6.6 PSK modulation .......................................................................................................31 4.7 Set System Parameters......................................................................................................32 4.8 Universal Counter .............................................................................................................34 5. REMOTE INTERFACE REFERENCE ...................................................................................35 5.1 Introduction ......................................................................................................................35 5.2 Overview and syntax of SCPI instructions .......................................................................35 5.3 Detailed description of SCPI Instructions ........................................................................39 6. USER PROGRAMMABLE ARBITRARY WAVEFORM MODULE ....................................47 7. APPENDIX ..............................................................................................................................57 A) Declaration of conformity .................................................................................................58 B) Service and Warranty Information .....................................................................................57 3 4080 series Function & Arbitrary/Function Generators -Instruction Manual Intentionally left blank 4 4080 series Function & Arbitrary/Function Generators -Instruction Manual 1. PRODUCT INTRODUCTION 1.1 Description The B&K Precision 4080 Series are laboratory grade synthesized function generators with a wide frequency range of up to 120 MHz. Direct digital synthesis (DDS) techniques are used to create stable, accurate output signals for clean, low distortion sine waves and an extensive selection of built-in standard and arbitrary waveforms. The instrument supports AM, FM, FSK, PSK and pulse modulation and linear and logarithmic sweep. Modulation parameters can be set precisely and are adjustable over a wide range. The 4080 Series supports internal and external modulation sources as well as internal, external and gated trigger sources. All models are capable of generating complex, predefined arbitrary waveforms. Additionally, models 4084AWG and 4086AWG provide the flexibility to create custom waveforms. The AWG module includes an intuitive, graphical Windows based software tool for creating and editing custom arbitrary waveforms and transferring the waveforms to the instrument's non-volatile memory. The software also provides a direct interface to Tektronix(R) TDS1000, TDS2000 TPS2000 and TDS3000 series digital storage oscilloscopes offering users a convenient means to recreate waveforms originating from the DSO's display or internal memory. The 4080 Series front-panel operation is straightforward. Parameters can be entered using the knob or directly via the numerical keypad and unit keys. The instruments are fully programmable via the standard RS232 interface. The command set is SCPI (standard Commands for Programmable Instruments) compatible. The combination of classical function and arbitrary waveform generator makes this series a versatile solution for many applications in Electronic Test and Design, Sensor Simulation, Education and Training. 1.2 Features Direct Digital Synthesis (DDS) architecture Wide frequency range of 1Hz ~ 120MHz (model 4087, sine wave only) Clean and stable output of very small signals down to 1mV (50) 27 build-in standard and complex waveforms. Eight downloadable 16000 point memories for custom arbitrary waveforms (models 4084AWG and 4086AWG only) Graphical Arbitrary Waveform Generation Software tool for Microsoft(R) WindowsTM (models 4084AWG and 4086AWG only) Convenient data input via knob or numerical keypad. Bright, easy to read display using VFD (Visible Vacuum Fluorescent) technology Fully programmable via SCPI compatible command set 100 MHz Universal Counter with frequency measurement and totalize function 5 4080 series Function & Arbitrary/Function Generators -Instruction Manual 2. SPECIFICATIONS 2.1 Function Generator Waveform Characteristics Main Waveforms: Sine, square Waveform Amplitude resolution: 12 bits Sample Rate: 200MSa/s (4084, 4084AWG, 4085, 4086, 4086AWG) 300MSa/s (4087) Sine: Harmonic Distortion of Sine Wave: - 50dBc (frequency 5MHz) - 45dBc (frequency 10MHz) - 40dBc (frequency 20MHz) - 35dBc (frequency 40MHz) - 30dBc (frequency > 40MHz) Total Harmonic distortion: 0.1% (20Hz ~ 100kHz) Square: Rise and Fall Time of Square Wave: 15ns Note: Test conditions for harmonic distortion, sine distortion, rise/fall time: Output Amplitude 2Vp-p, Environmental temperature: 255 Build in standard and complex (arbitrary) waveforms: 27 build-in standard and complex waveforms. Sine, Square, Triangle, Positive Ramp, Falling Ramp, Noise, Positive Pulse, Negative Pulse, Positive DC, Negative DC, Stair wave, Coded Pulse, Full wave rectified, Half-wave rectified, Sine transverse cut, Sine vertical cut, Sine phase modulation, Logarithmic, Exponential, Half-round, SINX/X, Square root, Tangent, Cardiac, Earthquake, Combination Waveform Length: 4096 dots Amplitude Resolution: 10 bits Pulse Wave: Duty Cycle: Rise/Fall Time: 0.1% ~ 99.9% (below 10kHz), 1% ~ 99% (10kHz ~ 100kHz) 100ns Duty cycle 20% DC signal characteristics: DC range: 10mV - 10V (high impedance) DC Accuracy: 5% of setting +10mV (high impedance) Module for user defined arbitrary waveform generation (models 4084AWG and 4086AWG only) Number of memory locations for arbitrary waveforms: 8 Length of waveforms8~16000 points Resolution of waveform amplitude10 bits Frequency range100Hz~100kHz 6 4080 series Function & Arbitrary/Function Generators -Instruction Manual Frequency Characteristics Frequency Range: Main waveforms (sine, square): Model 4084/4084AWG: 1Hz ~ 20MHz Model 4085: 1Hz ~ 40MHz Model 4086/4086AWG 1Hz ~ 80MHz (sine wave) 1Hz ~ 40MHz (square wave) Model 4087 1Hz ~ 120MHz (sine wave) 1Hz ~ 40MHz (square wave) All other waveforms: All models: 1Hz ~ 100kHz Frequency Stability: 1x10-6 (225 Resolution: Frequency Accuracy: Data entry Units: 1Hz 5x10-6 (225 s, ms, Hz, kHz, MHz Amplitude Characteristics Amplitude Range: 4084, 4084AWG: 2mV ~ 20Vpp (open circuit), 1mV ~ 10Vpp (50) 4085 4086, 4086AWG: for Freq 40MHz: 2mV ~ 20Vpp (open circuit), 1mV ~ 10Vpp (50) for Freq > 40MHz: 2mV ~ 4Vp-p (open circuit), 1mV ~ 2Vpp (50) 4087: for Freq 40MHz: 2mV ~ 20Vpp (open circuit), 1mV ~ 10Vpp (50) for Freq > 40MHz: -76dBm ~ +13.5 dBm50or 0.1mV ~ 3Vpp50 Max. Resolution: 2Vpp (open circuit), 1Vpp (50) Amplitude Accuracy: Amplitude Stability: 1%+0.2mV (sine wave relative to 1kHz) 0.5 % /3 hours Flatness: For amplitude 2Vpp: 3% (frequency5MHz), For amplitude >2Vpp: 5% (frequency5MHz), Models 4086/AWG, 4087 only: 10% (5MHz20MHz) 1dBm (frequency>40MHz) Output Impedance: 50 Output Units: Vpp, mVpp, Vrms, mVrms, dBm 7 4080 series Function & Arbitrary/Function Generators -Instruction Manual DC Offset Characteristics Offset Range (open circuit) Freq 40MHz): 10Vpk ac + dc (Offset 2xpeak-to peak amplitude) Freq > 40MHz): 2Vpk ac + dc (Offset 2xpeak-to peak amplitude) Resolution: 2V (open circuit), 1V (50) Offset Error: 5% of setting +10mV (Ampl. 2Vpp into open circuit) 5% of setting +20mV (Ampl. > 2Vpp into open circuit) AM Characteristics Carrier Waveforms: sine or square Carrier Frequency Range: same as main waveforms Modulation Source internal or external Modulating Waveform: 5 internal waveforms (sine, square, triangle, rising/falling ramp) Frequency of modulating signal: 100Hz ~ 20kHz Distortion: 2% Modulation Depth: 1% ~ 120% 1% ~ 80% (frequency>40MHz, Ampl > 2Vpp into open circuit) Modulation Error: 5%+0.2% (100Hz < frequency 10kHz) 10%+2% (10kHz < frequency 20kHz) Amplitude of ext. input signal: 3Vp-p (-1.5V~ +1.5V) FM Characteristics Carrier Waveforms sine or square Carrier Frequency Range: same as main waveforms Modulation Source: internal or external Modulating Waveform: 5 internal waveforms (sine, square, triangle, rising/falling ramp) Frequency of modulating signal: 100Hz ~ 10kHz Peak Frequency Deviation: Max. 50% of carrier frequency for internal FM Max 100kHz (carrier frequency5MHz) for external FM, with input signal voltage 3Vp-p (-1.5V~+1.5V) FSK Characteristics Carrier Waveform Carrier Frequency Range: Control Mode FSK Rate: PSK Characteristics Waveform: Frequency Range: PSK: Resolution: PSK rate: sine or square same as main waveforms internal or external trigger (external: TTL level, low level F1, high level F2) 0.1ms ~ 800s sine or square same as main waveforms Phase 1 (P1) and Phase 2 (P2), range: 0.0 ~ 360.0 0.1 0.1ms ~ 800s 8 4080 series Function & Arbitrary/Function Generators -Instruction Manual Control Mode: internal or external trigger (external: TTL level, low level P1, high level P2) Burst Characteristics Waveform: sine or square Frequency Range: same as main waveforms Burst Counts : 1 ~ 10000 cycles Time interval between bursts: 0.1ms ~ 800s Control Mode: internal, single or external gated trigger Frequency Sweep Characteristics Waveform: sine or square Start/Stop Freq.: same as main waveforms Sweep Time: 1ms ~ 800s (linear), 100ms ~ 800s (log) Sweep Mode: Linear or Logarithmic External trigger signal frequency: DC ~ 1kHz (linear) DC~10Hz (log) Control Mode: internal or external trigger Rear Panel Terminals (for modulation and sweep) Output MOD OUT Frequency: 100Hz ~ 20kHz Waveform: sine, square, triangle, rising/falling ramp Amplitude: 5Vp-p 5% Output Impedance: 600 Modulation IN 3 Vpp = 100% Modulation External Input Trig/FSK/Burst Level: TTL Main OUTput Impedance: Protection: 50 Short circuit and overload protected State Storage Characteristics Storage Parameters: frequency, amplitude, waveform, DC offset values, modulation parameters Storage Capacity: 10 user configurable stored states Storage Time: more than 10 years 2.2 Universal Counter Frequency Range Frequency Measurement: Totalize mode: 1Hz ~ 100MHz 50MHz max 9 4080 series Function & Arbitrary/Function Generators -Instruction Manual Input Characteristics Sensitivity Input attenuator disabled: Input attenuator enabled: 50mVrms (f: 10Hz ~ 50MHz), 100mVrms (f: 1Hz ~ 100MHz) 0.5Vrms (f: 10Hz ~ 50MHz), 1Vrms (f: 1Hz ~ 100MHz) Max. Input Voltage Allowed: 100Vp-p (f100kHz), 20Vp-p (1Hz~100MHz) Input Impedance: R>500k, C<30pF Coupling: AC Waveform: sine or square Low Pass Filter: cut off frequency about 100kHz (with internal attenuation: -3dB) with external attenuation: -30 dB (f >1MHz) Gate Time Setting: 10ms ~ 10s continuously adjustable Display Bits: 8 (for gate Time>5s) Totalize Capacity: 4.29x109 Control Mode: manual or external gate control Accuracy: time base error trigger error (when signal SNR > 40dB, trigger error 0.3) Time base: Type: small TCXO Frequency: 10MHz Stability: 1 x 10-6 (22C5C) 2.3 General AC Input Power Consumption: Operating Temperature Operating Humidity 198~242V or 99~121V, Frequency: 47~ 63Hz <35VA Storage Temperature -40 to 70 255 mm x 100 mm x 370 mm (10.0 x 3.93 x 14.56 inch) 3 kg (6.6 lbs): models 4084, 4084AWG, 4085, 4086, 4086AWG 3.5 kg (7.7 lbs) model 4087 RS232 Dimensions (W x H x D): Weight: Remote Interface 0 to +40 C 80% R.H Accessories included BNC to alligator cable BNC to BNC cable RS232 communication cable Power line cord Test report Spare fuse Installation disk for Arbitrary Waveform Creation Software (models 4084AWG or 4086AWG only) NOTE: Specifications and information are subject to change without notice. Please visit www.bkprecision.com for the most current product information. 10 4080 series Function & Arbitrary/Function Generators -Instruction Manual 3. PANEL DESCRIPTION 3.1 Front Panel 3.1.1 Overview of Keys: Summary: Most keys have multiple functions. Primary functions are written on the key. Simply press the respective key to enable a primary functions. All Function/Mode keys and some of the numerical entry keys have associated secondary functions indicated above each key in blue. To activate a secondary function, press the shiftkey followed by the desired key. The bottom row of the Function/Mode keys can be used to enter units directly. The unit is indicated below each key. To enter a unit, enter a numerical value via the numerical keypad then press the corresponding unit key. The unit key also serves as Enter function. Data entry keys: Key Name *: Main Function 0 Input Digit 0 1 Input Digit 1 2 Input Digit 2 3 Input Digit 3 4 Input Digit 4 5 Input Digit 5 6 Input Digit 6 Secondary Function Key Name Enter SW mode 7 Input Digit 7 8 Input Digit 8 9 Input Digit 9 Not available Input decimal point Reset Unit Input negative symbol Move arrow key to left * Move arrow key to right ** Enable ARB1 waveform *** Enable ARB2 waveform *** Enable ARB3 wave *** Enable ARB4 waveform*** Enable ARB5 waveform *** Enable ARB6 waveform*** Main function Secondary Function Enable ARB7 waveform ***. Enable ARB8 waveform *** Enter system menu Select pulse Select Arblist waveform Direct number entry: Press this key to clear the least significant bit of the displayed number. Useful for correcting number entry before entry is confirmed with unit key. External totalize mode: Press this key to stop counting and display present counting value. Press again to resume counting. 11 4080 series Function & Arbitrary/Function Generators -Instruction Manual **: External totalize mode: Press this key to reset and resume event counter *** models 4084AWG and 4086AWG only Function/Mode Keys: Key name Freq./Period Toggle between Frequency & Period. Ampl./Pulse width Amplitude Select. FSK/PSK FSK/PSK Function Select Menu Menu Selection FM Enable FM mode AM Enable AM mode Enable Sweep mode Enable Burst mode Sweep Burst Secondary Function Main Function Enable Sine Wave Enable Square Wave. Enable Triangle Wave Enable positive ramp Enter Storage menu Enter Recall menu Enter Counter Mode DC Offset Select Secondary Function for Counter Mode Unit Entry Not Available Not Available Not Available Not Available Not Available Not Available Not Available Not Available Attenuation Selection Low Pass Select Freq. Meas./ Totalize Enable Gate Select ms, mVpp MHz, Vrms kHz, mVrms Hz, dBm Other Keys: Key Name Main Function Output Main OUTPUT signal On/Off Shift Select secondary function Other Function Generate single trigger in sweep and burst mode Enter units in s, Vpp, N 3.1.2 Display Annunciators: Display areas: Waveform Indication Main Alphanumeric Display Frequency Measurement/Totalize Settings Instrument states 12 4080 series Function & Arbitrary/Function Generators -Instruction Manual Waveform states Sine waveform is enabled (,main waveform) Square waveform is enabled (main waveform) Triangle waveform is enabled Ramp waveform is enabled Arb Arbitrary waveform mode is enabled Frequency Measurement/Totalize states Filter: Low Pass Filter is enabled ATT: Input Attenuator is enabled GATE: Gate received trigger Function Generator states Adrs: The instrument is in remote state. Trig: Function Generator is waiting for a single trigger or external trigger. FM: FM modulation is enabled AM: AM modulation is enabled Sweep: Sweep mode is enabled Ext: Generator is configured for external signal input Freq: Frequency measurement function is enabled Count: Totalize function is enabled FSK: FSK (frequency shift keying) modulation is enabled FSK: PSK modulation is enabled Burst: Burst mode enabled. Offset: DC offset of output signal is not 0. Shift: Shift key has been pressed, Shift mode is active Rmt: The instrument is in remote state. 3.13 Description of front panel keys shiftkey Access secondary functions or to enter units "seconds", Vpp and "N" Numerical key pad: Keys are used for direct entry of numerical values. Keys0 -are assigned secondary functions to enter the systems menu, reset the unit to its default values or revert to Standard Waveform ("SW") mode. arrow keys The primary function is to move the flashing digit left or right or to select the desired arbitrary waveform from the Arb List (secondary function). When in Counter Mode, these 2 keys are used to start/stop or reset/resume the counter. Freq/Periodkey: Toggle between frequency and period display (primary function) or to enable sine waveform. Ampl/Pulse Widthkey: Display and adjust the amplitude of waveforms or, when in pulse mode, toggle the display 13 4080 series Function & Arbitrary/Function Generators -Instruction Manual between amplitude and pulse width. The secondary function activates the square waveform FSK/PSKkey: Toggle between FSK and PSK modulation (primary function). Activate triangle waveform Menukey: Enter modulation parameters for FSK, PSK, FM, AM and burst modulation and for sweep mode. When in standard waveform mode (no modulation, main waveforms enabled), this key can also be used to toggle the units for the amplitude display value between Vpp, Vrms and dBm. (Press the Amplitude key first, then the Menu key to toggle between the units). The secondary function enables the ramp waveform. FMkey: Activate FM modulation (primary function). Enter Storage mode (secondary function). Enter units ms or mVpp after entering the desired value by numerical key pad. In Counter Mode, this key turns the input attenuator on or off. AMkey: Activate AM modulation (primary function). The secondary function is used to recall and recreate signals stored in status memory. Enter units "MHz and "Vrms" after entering the desired value by numerical key pad. Enable the low pass filter when in Counter mode. Sweep key: Activate sweep mode. Select frequency measuring and totalize mode (secondary function) . Enter units kHz or mVrms after entering the desired numerical value directly via the keypad. Use the Shift key to toggle between frequency measurements and totalize mode. Burstkey: Activate burst mode (primary function). Enter DC offset mode (secondary function). Enter units Hz or dBm. When in frequency measurement mode, press this key to enter the gate time. Outputkey Press this key to toggle the main OUTPUT signal between the ON and OFF state. By default the output is turned on, indicated by the green LED and the currently active wave form is available at the OUTPUT terminal. In Burst or Sweep mode, this key is also used to generate a single trigger. 3.14 Description of menu parameters Use this key to configure modulation parameters, sweep mode parameters and system parameters. Modulation and Sweep mode: After enabling modulation or sweep mode, press "menu" to configure the related parameters. Each time you press the menu key, the parameter will flash for 1 second, followed by the currently active value of that parameter. Use the knob or numerical keys to enter a new value. Once the parameter is set, press menu to advance to the next parameter. Continue pressing the menu key to cycle through all parameters. Press Shift SWto return to the main waveform mode and to set the carrier waveform parameters. Sweep Mode: MODE --> START F --> STOP F --> TIME -->TRIG ______________14 4080 series Function & Arbitrary/Function Generators -Instruction Manual MODE: Select LINEAR or LOGarithmic sweep START F :Sweep start frequency STOP F: Sweep stop frequency TIME: Sweep time TRIG: Select trigger source, INTernal or EXTernal FM modulation: FM DEVIA--> FM FREQ --> FM WAVE --> FM SOURCE FM DEVIA: Peak frequency deviation FM FREQ: Modulating signal frequency FM WAVE: Modulating signal waveform (sine, square, triangle rising or falling ramp) FM SOURCE: Toggle between internal and external modulating signal. AM modulation: AM LEVEL --> AM FREQ --> AM WAVE --> AM SOURCE AM LEVEL: Modulation depth AM FREQ: Frequency of modulating signal AM WAVE: Modulating signal waveform (sine, square, triangle rising or falling ramp) AM SOURCE Select internal or external modulating signal Burst modulation: TRIG --> COUNT --> SPACE T --> PHASE TRIG Select trigger source, internal or external COUNT: Number of burst cycles SPACE T:Burst time spacing PHASE: starting phase of the burst FSK modulation: START F --> STOP F--> SPACE T --> TRIG START F STOP F SPACE T TRIG Primary frequency (same as carrier wave) the second frequency (hop frequency) FSK rate Select trigger source, external or internal PSK modulation P1 --> P2 --> SPACE T --> TRIG P1 P2: phase value #1 phase value #2 15 4080 series Function & Arbitrary/Function Generators -Instruction Manual SPACE T: TRIG: PSK rate trigger mode, internal or external System Function Mode: POWER ON --> ADDRESS --> OUT Z --> INTERFACE-->..... ............BAUD --> PARITY --> BEEP POWER ON "Power on" state ADDRESS: set GPIB address (option) OUT Z: Configure amplitude display value for 50 or high impedance load termination INTERFACE: Select RS232 or GP-IB (IEEE-488) interface (option) BAUD: Baud rate for the RS232 interface PARITY: Parity and Data Bits configuration for RS232 BEEP: Toggle the key beep on/off 16 4080 series Function & Arbitrary/Function Generators -Instruction Manual 3.2 REAR PANEL Ext. Trig/FSK/Burst: Input Terminal for external trigger signals for FSK/PSK Burst modulation and sweep mode MOD In Apply modulating signal for AM and FM to this Input terminal Meas Freq/TOT In Input terminal for Universal Counter which operates in frequency measurement or Totalize mode MOD OUT The internally generated modulating signal when in AM mode will be available at this output RS232C RS232 interface for remote control of instrument (all models) or for download of custom arbitrary waveforms (models 4084AWG and 4086AWG only) AC Socket and fuse compartment Connect the supplied power line cord to this receptacle. Make sure to install the appropriate fuse according to the selected AC voltage. AC Input Selector switch Set this switch to the corresponding AC voltage in your area 17 4080 series Function & Arbitrary/Function Generators -Instruction Manual 4. OPERATING INSTRUCTIONS 4.1 Installation This section contains installation information, power requirements and initial inspection and signal connections for the 4080 series generators. Mechanical Inspection This instrument was carefully inspected before shipment. Upon receipt, inspect the instrument for damage that might have occurred in transit. If any sign of damage is found, notify your B+K Precision distributor. Instrument Mounting The 4080 Series is intended for bench use. The instrument includes a handle adjustable for optimum panel viewing angle. The instrument does not require special cooling when operated within conventional temperature limits. Power Requirements The 4080 Series can be operated from any source of 99V to 242V AC and frequency of 48Hz to 63Hz. The maximum power consumption is 35 VA. Replace fuses with the same type, according to the rating indicated on the rear panel of the instrument. The instrument power fuse is located in a fuse compartment below the AC input receptacle. To access the fuse, first disconnect the power cord and then remove the fuse cartridge. Power-on procedure Turn on the instrument by pressing the power key on the front panel of the unit. The display should be flashing "BK PRECISION" for 2 seconds followed by the model number. e.g. ."4084AWG" for 1 second. By default, the instrument will enter the standard waveform ("SW") mode with the frequency set to 10.00000000 kHz and the waveform annunciator displaying the "~ " symbol. If the Power ON configuration in the systems menu was modified, the parameters of the last operation before power-down will be displayed. 4.2. Main operating modes "SW" standard waveform mode In this mode, the generator outputs any of the 27 build-in waveforms, including the 2 "main waveforms" sine and square. This also includes the 8 user programmable arbitrary waveforms (models 4084AWG and 4086AWG only). For most waveforms, you can set frequency, amplitude and DC offset. In this mode, modulation and sweep is not active and all annunciators in status area 4 are turned off. When modulation or sweep is enabled, pressshift SWto return to this mode. Modulation, Pulse and Sweep Mode In this mode, the generator operates like a conventional function generator and the Arb annunciator is turned off. The user can select one of the modulation modes AM, FM, FSK, PSK, Burst or sweep mode. The 2 main waveforms sine and square can be used as carrier signal. There is a close, reciprocal relationship between the modulation/sweep mode and the standard 18 4080 series Function & Arbitrary/Function Generators -Instruction Manual waveform mode used to set the sine or square wave parameters. When one of the modulation modes is active, the parameters of the carrier wave are carried over from the Standard Waveform Settings (for sine or square). Pressshift SWto toggle between any of the modulation/sweep modes (to set the modulation parameters) and the standard waveform mode (to define the carrier settings for frequency, amplitude and DC offset). On the other hand, the carrier frequency can also be set in the modulation/sweep menus and if changed, will overwrite the standard waveform frequency setting. Example: When transitioning from standard waveform mode to FM modulation mode, (by pressing the FM button) the parameters set previously in "SW" mode carry over to the FM mode and are now defining the FM carrier. If the FM carrier frequency in the FM modulation menu is changed, it will also "overwrite" the frequency setting of the standard waveform" settings. To adjust the duty cycle, enable pulse mode by pressing shift . Note that the duty cycle can only be adjusted in pulse mode. 4.3 Waveform Selection: Enabling common waveforms Pressshift followed by the waveform key to select one of the 5 common waveforms sine, square, triangle, ramp and pulse. The corresponding waveform annunciator will be displayed in the waveform display area. Note that the instrument operates in Function Generator mode when selecting sine and square and in ARB mode for the remaining functions. (Arb annunciator is lit). Note: The 5 common waveforms can also be output by selecting the corresponding number from the ArbList in this section. Example: Press Shift FSK/PSKto enable the triangle waveform Enabling stored waveforms from the Arb List Make sure you are in "SW" mode. (All area 4 status annunciators are off). If modulation or sweep is active, pressshift SWto return to the standard waveform mode. Pressshift to enter the ArbList: Waveform,"6: NOISE" is enabled and appears on the display. Use the knob or the numeric keypad to select one of the 27 stored waveforms from the ArbList according to the table in this section. Example: To select negative ramp DOWN_RAMP, do the following: Press shift (enter ArbList) Press 5 N(enable DOWN_RAMP) or select waveform with the knob Models 4084AWG and 4086AWG only: Locations 28-35 are reserved for the storage of user defined arbitrary waveforms. The display name for these waveforms is ARB1-ARB8. These memory locations can be accessed in one of 2 ways: a) Enter the ArbList, then use the knob or the numeric keypad to enable waveforms ARB1 - ARB8 b) Press Shiftfollowed by any number between 1-8. Example: Press Shift 2to enable waveform stored in memory location ARB2 19 4080 series Function & Arbitrary/Function Generators -Instruction Manual Table of stored waveforms (ArbList) and their memory locations No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Waveform Sine wave Square wave Triangle wave Ramp Falling ramp Noise Pulse wave Positive pulse Negative pulse Positive DC Negative DC Stair wave Coded pulse Full wave rectified Display Name SINE SQUARE TRIANG UP_RAMP DOWN_RAMP NOISE PULSE P_PULSE N_PULSE P_DC N_DC STAIR C_PULSE No. 15 16 17 18 19 20 21 22 23 24 25 26 27 COMMUT_FU 28~35* Waveform Half-wave rectified Sine transverse cut Sine vertical cut Sine phase modulation Logarithmic function Exponential function Half-round function SINX/X function Square root function Tangent function Cardiac wave Earthquake wave Combination wave User programmable Arbitrary waveforms Display Name COMMUT_HA SINE_TRA SINE_VER SINE_PM LOG EXP ROUND_HAL SINX/X SQU_ROOT TANGENT CARDIO QUAKE COMBIN ARB1~ARB8 Note: *No 28~35: memory location for user programmable waveforms, models 4084AWG and 4086AWG only. Refer to chapter 7 for more details 4.4 Data entry Using the arrow keys and the knob Use the knob and arrow keys to modify the displayed number. Use the keys to move the flashing digits left or right then adjust the value with the knob. Using this method of entry, the output signal will be updated immediately. Move the arrow keys left for coarse adjustment and right for fine adjustment. To disable the knob, use the key to move the cursor all the way to the left or right until the digits stop flashing. Now data entry via the knob is disabled. Direct entry using the numerical key pad Use the numerical keypad to enter a number with the appropriate unit. Enter numbers from left to right. Use the key to enter a decimal point. Enter -for negative numbers. Repeatedly pressing this key will toggle between positive (no sign visible) and negative numbers. Numerical entries do not update the output signal until a unit key has been pressed. Once you entered the correct numerical value, press the appropriate unit key to assign a unit and to make the entry effective. The instrument will now output a signal according to the displayed data. For entries not associated with a unit, press the shift key ("N" = "no unit") to make the entry effective. Note: Numerical values entered via the keypad are not effective until a valid unit key or shift ("N") has been pressed. 20 4080 series Function & Arbitrary/Function Generators -Instruction Manual Entry of invalid key presses or invalid values If the entered value exceeds the rated range, a beep sound will be heard. If the entered value is below the lower limit, the instrument will automatically change the entry to the lowest possible value. If the entered value exceeds the upper limit, the instrument will automatically revert to the maximum value. Example: When trying to entering 90MHz in a model 4086 (80 MHz max), a beep will be heard and the value will be forced to 80 MHz. Invalid keys: A beep sound will inform the user that the key entry is invalid. The instrument will simply ignore the key pressed. Example: Key-is pressed when trying to enter a frequency value. The instrument will ignore the entry and respond with a "beep" sound. 4.5 Output Configuration 4.5.1 Set Frequency and Period Thefrequency/periodkey is used to toggle between Frequency and Period display of the standard waveform or the carrier waveform. Frequency Press the frequency key to display the current frequency value. The value can be modified using the numerical keypad or the knob. Example: To set a frequency value of 5.8 kHz, enter the following key sequence: frequency 5 8 kHz or frequency 5 8 0 0 Hz or use the knob and keys The display will be 5.80000000 kHz. Period Setting: The signal frequency can also be displayed or entered as a period value. If the current display is frequency, press thefrequency/periodkey to display the current period value. Values can be entered with the numerical key pad or using the knob. Example: To set a period value of 10ms, enter the following sequence of keys: Period 1 0 ms Or use the knob and keys 4.5.2 Set Amplitude Press theAmplitudekey to display the current amplitude value. Modify the value using the knob or the numerical keypad. Example: Set amplitude to 4.6V peak-to-peak: PressAmplitude 4 6 Vpp or modify values using the knob and arrow keys 21 4080 series Function & Arbitrary/Function Generators -Instruction Manual In case of standard waveforms "sine", "square", "triangle", "rising ramp" and "pulse", numbers can be entered and displayed as Peak-to-peak value (Vpp or mVpp) , root mean square value (Vrms and mVrms) or dBm value. All other waveforms can only be edited or displayed using Vpp or mVpp units only. 4.5.3 Set DC Offset Voltage Pressshift offsetto display the current DC offset value. If the current DC offset value is not equal to zero, the annunciator "Offset" will turn on. The DC offset value can be entered directly or using the knob. Example: Set an offset value -1.6V peak-to-peak Pressshift offset - 1 6 Vpp or shift offset 1 6 - Vpp or use the knob for value entry Zero Point Adjustment: For zero point adjustment of the output signal, using the knob is more convenient than direct entry via the numerical keypad. The transition of the DC offset Voltage from plus to minus sign will be automatic when passing through the zero point. The input range of the signal amplitude and DC offset should satisfy the following equation: |Voffset| + Vpp/2 Vmax, with the parameters defined as followed: Vpp is the peak-to-peak value of the amplitude |Voffset| is the absolute value of the DC offset Vmax is 10V at high impedance and 5V at 50 load. The following table shows the corresponding relationship between the Vp-p value of the amplitude and the absolute DC offset value at high impedance: Vp-p value of AC signal 1.001 V ~ 20.00 V 316.1 mV ~ 1.000 V 100.1 mV ~ 316.0 mV 31.01 mV ~ 100.0 mV 2.000 mV ~ 31.00 mV Absolute value of DC offset 0 ~ (10.000-Vpp/2) V 0 ~ 2.000 V 0 ~ 632.9 mV 0 ~ 200.9 mV 0 ~ 62.99 mV 4.5.4 Adjustment of duty cycle If the current waveform is pulse, and the current display value is amplitude, use the Ampl/Duty button to toggle between Amplitude and Duty cycle display. When the pulse width is displayed, enter a value via the numeric keypad or the knob. The valid range is 0.1% ~ 99.9% for frequencies below 10kHz with a maximum resolution of 0.1%. For frequencies between 10kHz~100kHz the range is 1% ~ 99% and the maximum resolution is 1%. Example: Enter a duty cycle value of 60.5% Press Pulse 6 0 5 N or use the knob and arrow keys 22 4080 series Function & Arbitrary/Function Generators -Instruction Manual 4.5.5 TTL Signal A TTL signal output is provided on the front-panel TTL terminal. All signals, including modulated signals and arbitrary waveforms (except DC and noise) have an associated TTL signal. This signal is a TTL "high" when the waveform's output (on the main terminal) is positive, relative to zero volts. The signal is a TTL "low" when the output is negative. The TTL signal is generated by passing the main output signal through a comparator configured as a Schmitt Trigger. The TTL signal will transition to high or low once the main output signal exceeds a certain threshold value, which causes a time delay between the main output signal and the TTL signal. 4.5.6 Signal Store and Recall Up to 10 different instrument states can be stored in non-volatile memory. This enables you to recall the entire instrument configuration with a single command from the remote interface or with just a few key presses from the front panel. The state storage feature "remembers" the function (including arbitrary waveforms), frequency, amplitude, DC offset, duty cycle, as well as any modulation parameters. To recall a stored state, you must use the same memory location used previously to store the state. The last state of the instrument before power-off is automatically stored in location #0, therefore a total of 11 groups locations ranging from 0 ~ 10 can be recalled. Example: Store the current output signal in group location #1: ShiftStore 1 N The following prompt will be displayed for a few seconds: "STORE Previously stored signal configurations will be overwritten. 1" To recall group location #1 and make it the active output signal: PressShift recall 1 N The following prompt will be displayed for a few seconds: "RECALL: 1" The stored signals can be continuously recalled and reproduced by scrolling through each location using the knob. 23 4080 series Function & Arbitrary/Function Generators -Instruction Manual 4.6 Set Modulation and Sweep Parameters 4.6.1. Sweep mode In the frequency sweep mode, the function generator "steps" from the start frequency to the stop frequency at a sweep rate which you specify. You can sweep up or down in frequency, and with either linear or logarithmic spacing. You can also configure the function generator to output a single sweep (one pass from start frequency to stop frequency) by applying an external trigger. The function generator can produce a frequency sweep for sine or square waveforms. Press Sweep to enable the frequency sweep mode. The display shows a preset frequency (start frequency) and the "Sweep" symbol appears in the state display area. The carrier frequency will be displayed and the frequency, amplitude, waveform and DC offset of the carrier signal can be set as described in previous sections of this chapter. The main functions sine or square wave can be selected as a carrier signal. Press the menukey repeatedly to cycle through the sweep menu parameters listed below. MODE --> START F --> STOP F --> TIME -->TRIG MODE Select LINEAR or LOGarithmic sweep mode START F sweep start frequency STOP F: sweep stop frequency TIME: sweep time TRIG: Select trigger source INTernal or EXTernal Each time you press the menu key, the parameter will flash for 1 second, followed by the value of that parameter. Sweep mode parameters can be entered via numerical keypad or the knob. Once the parameter is set, press menu to advance to the next parameter. Sweep mode MODE parameter: Select LINear (No.1) or LOGarthimic (No.2). In linear sweep mode, the output frequency changes in a linear fashion during a sweep, whereas in LOG mode the frequency changes exponentially. The spacing is calculated automatically based on start frequencies, stop frequencies and sweep time. Start frequency "START F": The frequency where the sweep starts is the start frequency. After displaying "START F" for 1 second, the current start frequency is displayed automatically and can be modified via knob or direct data entry. By default, the start frequency will carry over from the setting for the main wave form . Stop frequency "STOP F" The sweep stops at the frequency "STOP F" When the start frequency is lower than the stop frequency, the frequency sweep increases gradually from start frequency (low frequency) to stop frequency (high frequency); When the start frequency is higher than stop frequency, the frequency sweep decreases gradually from the start frequency (high frequency) to stop frequency (low frequency). 24 4080 series Function & Arbitrary/Function Generators -Instruction Manual The frequency range from start frequency to stop frequency is 1Hz ~ Fmax in linear sweep mode and 1mHz ~ Fmax in log sweep mode. (Fmax see specification section for main waveform) Sweep time "TIME" The time needed to complete one sweep from start to stop frequency is called sweep time. The sweep time range is 1ms ~ 800s in linear sweep mode or 100ms ~ 800s in LOG sweep mode. Trigger mode "TRIG": A sweep can be triggered internally or externally. The corresponding display values are "1: INT" and "2: EXT". The default value is INTernal trigger. In internal trigger mode, the instrument will continuously sweeps from the start frequency to the stop frequency according to the Sweep parameters. An external trigger signal can be generated in one of two ways. a) Press theoutputkey to trigger a single sweep. The signal frequency will in/decrease from start frequency to stop frequency, then sweep will stop. b) Apply an input trigger signal to the "EXT Trig" terminal on the rear panel. A rising edge will trigger a single sweep. In external trigger mode, symbols "Trig" and "Ext" are displayed in the status field. Start and stop of sweep The sweep will start automatically once sweep mode is selected. If you don't want to output the sweep signal, simply press the outputkey to disable the signal output (LED above Output button is OFF). Once all the parameters are set, you can make the sweep signal available at the output by pressing the Output button again. In external trigger mode, the Outputkey functions only as a single pulse trigger key, the Output On/Off functionality is now disabled and the output LED will always be lit. Sweep configuration example Sweep parameters are as followed: Frequency range 100Hz~200kHz, sweep time 10s, linear sweep, internal trigger mode. Set the carrier frequency parameters Presssweep Pressmenu Select "MODE", wait, then enter1 N(linear sweep) Pressmenuto select "START F", press1 0 0 Hz Pressmenuto select "STOP F", press2 0 0 kHz Pressmenuto select "TIME, press1 0 s Pressmenu to select "TRIG", press1 N Hint: The frequency displayed immediately after pressing [Sweep] is the start frequency. Any changes to that value will automatically update parameter "START F" 25 4080 series Function & Arbitrary/Function Generators -Instruction Manual 4.6.2 FM modulation A modulated waveform consists of a carrier waveform and a modulating waveform. In FM, the frequency of the carrier is varied by the amplitude of the modulating waveform. The function generator will accept an internal or external FM modulating signal. Press the FMkey to enter into FM mode. The display will indicate the carrier frequency and the "FM" annunciator will be lit. The frequency, amplitude, waveform and DC offset of the carrier signal can be set as described in the previous section. Only the main functions sine or square wave can be selected as a carrier signal. Press the menu key repeatedly to cycle through the FM modulation parameters listed below. FM DEVIA --> FM FREQ --> FM WAVE --> FM SOURCE FM DEVIA FM FREQ: FM WAVE: FM SOURCE Peak frequency deviation Frequency of modulating signal Waveform of modulating signal Toggle between internal or external modulating signal Each time you press the menu key, the parameter will flash for 1 second, followed by the value of that parameter. FM modulation parameters can be entered directly or via the knob. Once the parameter is set, press menu to advance to the next parameter. Peak frequency deviation "FM DEVIA" Explanation: The variation in frequency of the modulating waveform from the carrier frequency (center frequency). Range of deviation: For internal FM modulation, the maximum value should not exceed 50% of the carrier frequency. In external FM mode, the maximum deviation is 10% of the carrier frequency. Additionally, the frequency deviation plus carrier frequency should not exceed the maximum operating frequency of the instrument. (Fc + Fd <= Fmax + 100 kHz) For Fmax refer to the specifications for main waveforms. This parameter applies only when "FM SOURCE" is set to "INTernal". Modulating signal frequency "FM FREQ": The frequency range of the modulating signal is 100Hz ~ 10kHz. This parameter applies only when "FM SOURCE" is set to "INTernal". Modulating signal waveform "FM WAVE" Waveform of the modulating signal: Waveforms sine, square, triangle, rising and falling ramp can be used as the modulating signal. Waveforms are selected by entering the corresponding number, numbers 1 - 5. This parameter applies only when "FM SOURCE" is set to "INTernal". Modulating signal source "FM SOURCE": The modulating signal could be an internal signal and external input signal. The corresponding prompts are "1: INT" and "2: EXT", the default is INTernal signal. The external modulating signal is applied to terminal "Mod In" on the rear panel (max signal amplitude is 3Vp-p). When 26 4080 series Function & Arbitrary/Function Generators -Instruction Manual modulating signal source "external" is selected, the symbol "Ext" is displayed and parameters FM DEVIA, FM FREQ and FM WAVE do not apply (disabled) Start and stop of FM modulation An FM signal is generated once FM function mode is selected. The instrument will automatically output a signal according to the preset parameters. If you do not want to output the FM signal, simply press theoutputkey to disable the signal output (LED above Output button is OFF). Once all the parameters are set, you can turn make the FM signal available at the output by pressing the Output button again. FM example: Example configuration: Carrier signal is square, frequency is 1MHz, amplitude is 2V, modulating signal is generated internally. Carrier waveform is sine (No. 1), Frequency is 5kHz. Peak frequency deviation is 200kHz. PressFM Pressfrequencythen1 MHz (set carrier frequency) Pressamplitude, then2 V (set carrier amplitude) PressShiftand square (set carrier waveform) Pressmenu, select "FM DEVIA", enter2 0 0 kHz (set FM deviation) Pressmenu, select "FM FREQ", press5 kHz (set FM frequency) Pressmenu, select "FM WAVE, press1 N (set FM waveform as sine) Pressmenu, select "FM SOURCE", press1 N (set FM source as internal) 4.6.3 AM modulation AM stands for amplitude modulation. PressAMto enable AM modulation. The carrier frequency and the AM annunciator is displayed. Frequency, amplitude, waveform and DC offset of the carrier signal can be set as described in the previous section of this chapter. The parameters carry over from the parameter settings of the main waveforms sine and square. In AM only sine and square waves can be selected for carrier. Press the menu key repeatedly to cycle through the AM modulation parameters listed below. AM LEVEL--> AM FREQ --> AM WAVE-->AM SOURCE AM LEVEL: AM FREQ: AM WAVE: AM SOURCE: Modulation depth Frequency of modulating signal Waveform of modulating signal internal or external modulating signal In AM mode, to ensure normal signal output at 100% modulation depth, the instrument reduces the peak-to-peak value of the carrier by 50%. Only sine and square waves can be selected as AM carrier. 27 4080 series Function & Arbitrary/Function Generators -Instruction Manual Modulation depth "AM LEVEL": The range of modulation depth is 1% ~ 120%. Modulating frequency "AM FREQ" Frequency of the modulating signal. Range is 100Hz ~ 20kHz. Parameter does not apply when "AM SOURCE" is set to "EXTernal" Modulating signal waveform "AM WAVE": Waveforms sine, square, triangle, rising and falling ramp can be used as the modulating signal. Waveforms are selected by entering the corresponding number, numbers 1 - 5. Parameter does not apply when "AM SOURCE" is set to "EXTernal" Modulating signal source "AM SOURCE" Select internal signal and external input signal. The number and prompt symbols are 1: INT, 2: EXT. The default of the instrument is internal signal. The external modulating signal is input through the rear panel "Modulation Input" terminal (with a maximum signal amplitude of 3Vp-p). Enabling and disabling the AM signal: An AM signal is generated once AM modulation is selected. The instrument will automatically output a signal according to the preset parameters. If you do not want to output the AM signal, simply press theoutputkey to disable the signal output (LED above Output button is OFF). Once all the parameters are set, you can make the AM signal available at the output by pressing the Output button again. AM example: Configuration: carrier signal is square wave, frequency 1MHz, amplitude 2V, internal signal, modulating waveform sine wave (No.1), modulating signal frequency 5kHz, modulation depth 50%: PressAM (activate AM modulation) Pressfrequency, then1 MHz (set carrier frequency) Pressamplitude, then2 V (set carrier amplitude) Pressshift thensquare (set carrier waveform) Pressmenu, select "AM LEVEL", press5 0 N (set modulation depth) Pressmenu, select "AM FREQ", press5 kHz (set modulating signal frequency) Pressmenu, select "AM WAVE", press1 N (set AM wave as sine) Pressmenu select "AM SOURCE", press1 N (set AM source to internal) 4.6.4 Burst modulation You can configure the function generator to output a waveform with a specified number of cycles, called a burst. You can output the burst at a rate determined by the internal rate generator or an external signal applied to the rear-panel connector. The function generator can produce a burst using sine or square waveforms. PressBurstto enter into burst mode. The carrier frequency and the Burst annunciator are displayed. Frequency, amplitude, waveform and DC offset of the carrier signal can be set as 28 4080 series Function & Arbitrary/Function Generators -Instruction Manual described in the previous section of this chapter. The parameters carry over from the parameter settings of the main waveforms sine and square. Press the menu key repeatedly to cycle through the burst menu parameters listed below. TRIG --> COUNT --> SPACE T --> PHASE TRIG: COUNT: SPACE T: PHASE: Trigger source Number of cycles Burst time spacing The starting phase of the burst Select trigger source "TRIG" Three trigger sources are available. Internal trigger and 2 types of external triggers sources, external gated and single. The corresponding menu parameters are 1: INT, 2: EXT and 3: SINGLE. The default is internal triggering. a) Internal trigger When the internal trigger source is selected, the frequency at which the burst is generated depends on parameter SPACE_T, burst count and the burst carrier frequency. b) Single trigger mode Generate a single trigger event by pushing the outputkey once or by applying a single TTL pulse at the "Ext.Trig" input terminal in the rear panel. A single burst with predefined parameters will be generated. c) External gated burst mode The TTL signal applied to "Ext. Trig" input terminal in the rear panel will enable or disable the output of the generator. When the TTL level of the gate signal is high, the generated will generate burst pulses according to the parameters of the set carrier frequency. Burst parameters COUNT and SPACE_T are ignored in this mode. Anunciators "Trig" and "Ext" turn on when this mode is active. Burst count "COUNT": Definition: The number of cycles to be output per burst. Range: 1 ~10000 cycles in 1 cycle increments. Additionally, the minimum number of cycles must also satisfy FC/50khz +1Parameter does not apply when "TRIG" is set to "EXTernal". Burst spacing time "SPACE T": Definition: Time interval between the 2 consecutive groups of bursts (time interval during which there is no burst signal present) Parameter does not apply when "TRIG" is set to "EXTernal" or "SINGle". Range: 0.1ms ~ 800s. Starting phase of the burst "PHASE" Burst phase: 0.0 ~ 360.0 in 0.1 increments 29 4080 series Function & Arbitrary/Function Generators -Instruction Manual Enabling/disabling the burst signal The generator outputs a burst as soon as the burst key is pressed. The instrument will automatically output a signal according to the preset parameters. If you do not want to output the burst signal, simply press theoutputkey to disable the signal output (LED above Output button is OFF). Once all the parameters are set, you can make the burst signal available at the output by pressing the Output button again. Note that the output on/off function does not apply when single trigger mode is selected. Burst example: Configuration: Burst is sine wave with frequency 20kHz, amplitude 2V, 10 cycles per group, spacing time between each group 10 ms, start phase 90.0 Pressburst (enter into burst mode) Pressfrequency, press2 0 kHz (set wave form frequency) Pressamplitude, press2 V (set waveform amplitude) Pressshiftandsine (set waveform) Pressmenu, select "TRIG", press1 N (set trigger mode as internal) Pressmenu, select "COUNT", press1 0 N (set number of bursts/cycles) Pressmenu, select "SPACE T", press1 0 ms (set space time) Pressmenu, select "PHASE", press9 0 N (set the start phase of burst) 4.6.5 FSK modulation You can configure the function generator to "shift" its output frequency between two preset values using FSK modulation. The rate at which the output shifts between the two frequencies ("carrier frequency" and "hop frequency") is determined by the internal rate generator or the signal level on the rear-panel ext Trig/FSK/Burst terminal. PressFSK/PSK to enable FSK modulation. A preset frequency and the FSK annunciator is displayed. The preset frequency is identical to the "START F" parameter. Any changes automatically update "START-F" and vice versa. Frequency, amplitude, waveform and DC offset of the carrier signal can be set as described in the previous section of this chapter. In FSK/PSK only sine and square waves can be selected as carrier wave. Press the menu key repeatedly to cycle through the FSK menu parameters listed below. START F --> STOP F--> SPACE T --> TRIG START F: STOP F: SPACE T: TRIG: First frequency or carrier frequency Second frequency (hop frequency) FSK rate Trigger source Trigger source "TRIG" Select internal signal and external input signal, 1: INT or 2: EXT. The default of the instrument is 30 4080 series Function & Arbitrary/Function Generators -Instruction Manual "internal". In internal mode, the rate at which the signal shifts between the carrier and hop frequency is determined by the FSK rate. In external trigger mode, the trigger signal applied to the trigger input terminal on the rear panel determines the FSK rate. Logical "high" of the trigger signal is associated with frequency 2, while the "Low" level of the trigger signal is associated with frequency 1. Frequency 1 "START F" The first frequency or carrier frequency. Frequency 2 "STOP F" Second frequency or hop frequency Frequency input range of frequency 1 and frequency 2 is 1Hz ~ Fmax. Spacing time "SPACE T": This parameter sets the FSK rate with a range of 1ms ~ 800s. FSK example: Configuration: Sine signal of 2V output amplitude, carrier frequency 20kHz and hopping frequency 600 kHz, FSK rate 10ms PressFSK/PSK (enter into FSK function mode) PressAmpl/Duty, press2 V (set waveform amplitude) Pressshiftandsine (set waveform) Pressmenu, select "TRIG", enter1 N (set trigger mode as internal) Pressmenu, select "START F", enter2 0 kHz (set carrier frequency F1) Pressmenu, select "STOP F", enter6 0 0 kHz (set hop frequency F2) Pressmenu, select spacing time "SPACE T", press1 0 ms (set spacing time) 4.6.6 PSK modulation You can configure the function generator to "shift" its output phase between two preset values using PSK modulation. The rate at which the output shifts between the two phases is determined by the internal rate generator or the signal level applied to the trigger input terminal on the rear-panel. Press FSK/PSK twice to enter phase shift keying (PSK) mode. The carrier frequency will be displayed along with the symbol "" and "FSK". Frequency, amplitude, waveform and DC offset of the carrier signal can be set as described in the previous section of this chapter. The parameters carry over from the parameter settings of the main waveforms sine and square. If FSK mode was already active, press this key only once, (this key toggles the modulation between FSK and PSK mode). In FSK mode only sine and square waves can be selected as a carrier signal. Press the menu key repeatedly to cycle through the burst menu parameters listed below. P1 --> P2 --> SPACE T --> TRIG P1 Phase value #1 31 4080 series Function & Arbitrary/Function Generators -Instruction Manual P2: SPACE T TRIG phase value #2 PSK rate Trigger source for PSK Trigger source "TRIG" Select internal signal and external input signal 1: INT or 2: EXT. The default of the instrument is internal. In internal mode, the phase of the output signal shifts according to the PSK rate parameter. In external trigger mode, the trigger signal is applied to the Ext. Trig" Input terminal on the rear panel. In external trigger mode, the trigger signal applied to the trigger input terminal on the rear panel determines the PSK rate. Logical "high" of the trigger signal is associated with phase value #2, while the "Low" level of the trigger signal is associated with phase value #1. Phase 1 "P1" The first start phase value of the PSK output signal. Input range of phase 1 and phase 2 is 0.0~ 360.0. Phase 2 "P2" The second start phase value of the PSK output signal. Input range of phase 1 and phase 2 is 0.0~ 360.0. Spacing time "SPACE T" PSK rate: Range is 0.1ms ~ 800s. PSK example Configuration: Sine signals with 600 kHz output frequency, 2V amplitude, phase alternating between 90.0 and 180.0, PSK rate is 10ms PressFSK/PSK (2 times if necessary to enter PSK mode) PressFreq/Period, enter6 0 0 kHz (set waveform frequency) PressAmpl/Duty, enter2 V (set waveform amplitude) Pressshift sine (set waveform) Pressmenu, select "TRIG", enter1 N, (set trigger mode as internal) Pressmenu, select "P1", enter9 0 N (set phase 1) Pressmenukey, select "P2", enter1 8 0 N (set phase 2) Pressmenu, select "SPACE T", enter1 0 ms (set PSK rate) 4.7 Set System Parameters PressShiftandsystemto enter the Systems menu. "SYSTEM" will flash on the display. Repeatedly pressmenuto cycle through the system parameters indicated below. POWER ON --> ADDRESS --> OUT Z --> INTERFACE-->.... ............BAUD --> PARITY --> BEEP 32 4080 series Function & Arbitrary/Function Generators -Instruction Manual POWER ON "Power on" state ADDRESS: set GPIB address (option) OUT Z: Configure amplitude display for 50 or high impedance load termination INTERFACE: Select RS232 or GP-IB (IEEE-488) interface (option) BAUD: Baud rate for the RS232 interface PARITY: Parity and Data Bits configuration for RS232 BEEP: Toggle the key beep on/off After the selected system parameter flashes for 1 second, the parameter value will be displayed and the value can be edited using the knob or via direct entry using the numerical keypad. Power on state "POWER ON: This parameter has 2 possible values, "1: DEFAULT" or "2: LAST STATE". In determines the initial setting of the instrument after power up. The factory setting is "1: DEFAULT". The default state is main waveform sine wave, 10kHz, 2Vpp which is identical to the state the instrument is in after pressing "Reset". When selecting "2: LAST STATE", the instrument will "remember" the last state the unit was in before power was turned off. The power on state is stored in non-volatile memory, location 0 (see Store/Recall section) GPIB address "ADDRESS" The default of GPIB interface address is 1. It can be set within 0 ~ 30. Output impedance "OUT Z" The generator has a fixed output impedance of 50 ohms on the OUTPUT terminal. You can specify whether you are terminating the output into a 50 ohm load or an open circuit. Incorrect impedance matching between the function generator and your load will result in amplitude or offset which does not match the specified signal level. Select "1: HIGH Z" or "2: 50 OHM" according to your load configuration. "INTERFACE" selection Select RS232 ("2: RS232"), GPIB ("1: GP-IB") or USB ("3: USB"). The default is RS232. "BAUD" rate setting Set the baud rate for the RS232 interface. Possible baud rates are 9600, 4800, 2400, 1200, 600 and 300. The default rate is 9600 ("1: 9600") "PARITY" setting Set parameters parity bit and number of data bits. Possible configurations are: None/ 8 data bits ("1: NONE 8 BITS") Odd/ 7 data bits ("2: ODD 7 BITS" Even/ 7 data bits ("3: EVEN 7 BITS"). The default setting is None/ 8 data bits. 33 4080 series Function & Arbitrary/Function Generators -Instruction Manual "BEEP" setting Turns the key beep on or off. Select OFF("1: CLOSE") or ON ("2: OPEN"). The default is ON. Example for system function setting Configuration: Set power on state [POWER ON] to default and output impedance to 50 PressShift system (enter systems menu) Pressmenu, "POWER ON", press1 N (set power on state to default) Pressmenu, select "OUT Z", press2 N (configure for load impedance of 50) 4.8 Universal Counter Overview of Counter functions This instrument contains a counter with frequency measurement and totalize functionality which is completely independent from the Arbitrary/function generator section. The range of the frequency measurement function is 1Hz ~ 100MHz. Repeatedly pressingShift Countwill toggle between Frequency measurement and Totalize mode. PressShiftandF.C./TOTonce to activate the frequency measurement mode. Symbols "Ext" and "Freq" will be displayed in the state field and "WAITING" will flash on the main display. The unit is now ready to measure and display the frequency of a signal applied to the input terminal "Meas Freq/TOT IN" in the rear panel. When totalize mode is active, symbols "Ext" and "Count" will be displayed on the status field along with the result for the count on the main display ("0" is displayed until a valid signal is detected). The unit is now ready to totalize events represented by the signal applied to input terminal "Meas Freq/TOT IN" in the rear panel In event counting mode, press the key to start and stop the event counter. When stopped, the current count will be displayed. Presskey to reset the event counter to zero and resume counting. Gate time Only applies to frequency measurement mode. PressShift gateto enter a gate time setting. Either the numerical keypad or the knob can be used to enter a gate time value. If the gate is open, the symbol "GATE" is displayed in the counter state field on the right. The range of gate times is 10ms ~ 10s Low pass filter By pressing Shift LPF, the input signal will be passed through a low pass filter before being passed onto the counter circuit. The word "Filter" appears on the right display field to indicate that the Low Pass Filter is active. Attenuation PressShift ATT to activate the attenuator which attenuates the input signal by a factor 10:1. "ATT" is displayed on the right to indicate that the input attenuator is active. 34 4080 series Function & Arbitrary/Function Generators -Instruction Manual 5. REMOTE INTERFACE REFERENCE 5.1 Introduction An Introduction to the SCPI Language SCPI (Standard Commands for Programmable Instruments) is an ASCII-based instrument command language designed for test and measurement instruments. SCPI commands are based on a hierarchical structure, also known as a tree system. In this system, associated commands are grouped together under a common node or root, thus forming subsystems. A portion of the SOURCE subsystem is shown below to illustrate the tree system. SOURce: FREQuency: STARt {|MINimum|MAXimum} FREQuency: STARt? [MINimum|MAXimum] FREQuency: STOP {|MINimum|MAXimum} FREQuency: STOP? [MINimum|MAXimum] SOURce is the root keyword of the command, FREQuency is the second-level keywords, and STARt and STOP are third-level keywords. A colon (: ) separates a command keyword from a lower-level keyword. Preparations for Remote Operation The Arbitrary/Function Generator series 4080 can be remotely controlled from a PC via the standard RS232 interface. Make sure to configure the RS232 interface to match the settings on your PC by setting the parameters in the Systems menu accordingly. The instrument enters the remote state after any remote command is received at which time all keys except of theLocalkey (Shift) are locked When in Remote mode, the instrument can be returned to Local mode by pressing the Local key or by sending a "LOCAL instruction via the RS232 interface. 5.2 Overview and syntax of SCPI instructions This section summarizes the SCPI commands available to program the function generator over the remote interface. Refer to the later sections in this chapter for more details on each command. Throughout this manual, the following conventions are used for SCPI command syntax. * Square brackets ([ ]) indicate optional keywords or parameters. * Braces ({ }) enclose parameters within a command string. * Triangle brackets (< >) indicate that you must substitute a value for the enclosed parameter. * A vertical bar (|) separates multiple parameter choices. Command Summary APPLY instruction 35 4080 series Function & Arbitrary/Function Generators -Instruction Manual APPLy:SINusoid [, , ] APPLy:SQUare [, , ] APPLy:TRIangle [, , ] APPLy:UP_RAMP [, , ] APPLy:DOWN_RAMP [, , ] APPLy:NOISe [*, , ] APPLy:P_DC [,* , ] APPLy? *: if waveform is Noise or DC, the frequency data contained in the command is not invalid. OUTPUT instructions [SOURce:] FUNCtion SHAPe {SINusoid|SQUare|TRIangle|UP_RAMP|DOWN_RAMP| NOISe|PULSe|P_PULSE|N_PULSE|P_DC|N_DC|STAIR| C_PULSE|COMMUT_FU|COMMUT_HA|SINE_TRA| SINE_VER|SINE_PM|LOG|EXP|ROUND_HAL| SINX/X|SQU_ROOT|TANGent|CARDIO|QUAKE|COMBIN} FUNCtion:SHAPe? [SOURce:] FREQuency FREQuency? [SOURce:] PULSe:DCYCle PULSe:DCYCle? [SOURce:] VOLTage VOLTage? VOLTage: OFFSet VOLTage: OFFSet? [SOURce:] OUTPut:LOAD {50|INFinity} OUTPut:LOAD? INPUT:FILTER INPUT:FILTER? INPUT:ATTenuator INPUT:ATTenuator? *SAV {0|1|2|3|4|5|6|7|8|9|10}. State 0 is the working state of the instrument before power off *RCL {0|1|2|3|4|5|6|7|8|9|10}. States 1--10 are user defined working states RF:STATe RF:STATe? MODULATION instructions [SOURce:] 36 4080 series Function & Arbitrary/Function Generators -Instruction Manual AM:DEPTh AM:DEPTh? AM:INTernal:FUNCtion {SINusoid|SQUare|TRIangle|UP_RAMP|DOWN_RAMP|} AM:INTernal:FUNCtion? AM:INTernal:FREQuency AM:INTernal:FREQuency? AM:SOURce {INTernal|EXTernal} AM:SOURce? AM:STATe {ON|OFF} AM:STATe? [SOURce:] FM:DEViation FM:DEViation? FM:INTernal: FUNCtion {SINusoid|SQUare|TRIangle|UP_RAMP|DOWN_RAMP|......} FM:INTernal: FUNCtion? FM:INTernal: FREQuency FM:INTernal: FREQuency? FM:SOURce {INTernal|EXTernal} FM:SOURce? FM:STATe {ON|OFF} FM:STATe? [SOURce:] BM:NCYCles <#cycles> BM:NCYCles? BM:PHASe BM:PHASe? BM:INTernal: Space