Operation manual in PDF format ~650Kb
Contents
1. Amphtfication Harmoruz Options GPIB address 10 Summary number 10 Archive number 41000 GENERATOR 120 180GHZ Noise level 0 13 Message log Power control Amplhtude modulation Mem control 7 fede a i si Spectrum 117 84 182 27 GHz Time 0 01 Resolution 18 1 MHz Sweep Remote Calibration Esi Supplement 19 Fig 3 Options GPIB address L Fix 120 00 1126 00 12200 1135 00 14400 150 00 156 00 16200 16800 17400 180 00 Summary number 10 0 120 00 1126 00 5203 14400 15000 156 00 16200 16800 17401 180 00 Archive number 00 a TT Noise level a _Search_ Calibration jeg ses m Message log E L Awolck 77 Summary sweep trat programm i 5 PIB 15 working properly gt 0z 2 utocabbration done 2 52 not response dms PIB is working properly ound 11 markers anualcabbration done 10 ound 11 markers 0 53 0 a 0 5 I I l 117 8 125 0 120 0 155 0 140 0 145 0 150 0 155 0 150 0 165 0 170 0 175 0 122 3 ie id wi2. 32 Switch on off When the generator is turn Generator Harmonic on LED integrated in the Generator button lights Amplification Corresponding LED integrated in the button lights Generator Waveguide flange on the waveguide input right panel of Receiver Signal Waveguide flange on the waveguide input right panel of Receiver 34 9 8 3 3 Output Front 34 Output Video Signal 100VAC 220VAC Rear 39 Switching of AC switch Input Voltage 100 220 V Generator Rear 38 Input Output signals Control connector of remote control 37 SUPPLEMENT 12 Front panel of the Receiver Plugs and buttons disposition on the front panel of the Receiver 31 Power indicator and on off switch 32 Harmonic generator switch on off 33 Gain control 34 Outputs plug 0 5 V 35 RF input 36 LO input 38 SUPPLEMENT 13 Rear panel of the Receiver GENERATOR 100VAC 220VAC FUSE 1A POWER PLUG Plugs disposition on the rear panel of the receiver 37 Fuse 1A 38 Generator control plug 10 pins 39 Switch 100 220V AC 40 Power plug 39 SUPPLEMENT 14 Block diagram of the Receiver Connector Generator Strobe from G3 X28 X31 Harmonic Generator Power Supply TRANSFORMER 12V 12V 5V 24V sre relay 100 Video Amplifier d Preamplifier e He Keyboard Output 40 SUPPLEMENT 15 Electrica
3. Denial necem EPF cann in Disposition of the plugs and knobs on the front panel of the Generator Power switch Power indicator Ready indicator Reset button Liquid Crystal Display Tuning knob Step knobs Digital keyboard 9 Microwave output 10 External broadband frequency input 2 9 V Il External frequency control switch 12 Menu button 13 Amplitude modulation mode switch 14 External power control switch 15 External power control 0 5V input 16 External Triggering TTL input 17 External VGA monitor and keyboard under left panel De 25 Ground 24 25 26 2 Strobe AM signal output plug TTL 29 30 SUPPLEMENT 2 Rear panel of the Generator C3 e EU COEM X X Disposition of the plugs and knobs on the rear panel of the Generator Operating Time counter GPIB interface plug Fuses Fuse 5A protection 5V Power Plug AC 220V High Voltage Monitor output plug Strobe FM signal output plug TTL Receiver plug for connecting with receiver 21 SUPPLEMENT 3 Disposition of the units in the Generator High Voltage Isolator Oscillator Unit BWO Modulator Unit Control Unit 1 2 V 16 V 5 V BOO BWO current Voltage Sources with tection POM pro BWO heater current circuit protection circuits Controlled High Voltage Source SUPPLEM
4. 6 and then press key Menu 12 Output operation frequency changes synchronously with value indicated on the display Press buttons Step or gt 7 and then press key Menu 12 This way is useful if it is necessary to provide precision tuning One button realising leads to the change of the frequency on the smallest available step Output operation frequency changes synchronously with value indicated on the display Enter frequency from Digital Keyboard 8 A marker will appear on the display just after the realising of one of the keys 8 One can use buttons Step or gt 7 to change the marker 5 8 position That allows edit the frequency on the display Press key Enter to finish editing and change the output operation frequency Press key Menu 12 If one will try to enter a wrong frequency out of operating frequency range max or min one available will be installed correspondingly One can combine these three cases If one enter he frequency using Digital Keyboard Generator sets the nearest frequency from frequency grid that reflects the fact that output voltage of controlling 12 bits DAC s cant be installed with accuracy better then 1 4096 If one try to enter a frequency that isn t fitted to the grid exactly the fitting will be produced automatically Press Menu button 12 to abort local menu C Zoom frequency window mode In this mode Generator provides frequency
5. Lens 8 GHz regime with the chosen central frequency on the Generator and let it warming up for 15 min 4 Switch the Harmonic Generator on Perform the calibration over the two marks 6 Switch the Harmonic Generator off and open the RF attenuator according to point 10 in the present Section Other Lens regimes see Section C of the G4 143 Manual provide better frequency resolution but the calibration based on the frequency marks can not be carried out that results in worse accuracy of the frequency measurement because the preliminary calibration file will be used instead View save Data in arc format by 3DVIEW program Run 3DVIEW exe Press LOAD Fig 4 Sup 19 Choose file for viewing Press Next or Prev for moving thought viewing file Zoom allows to change quantity viewing spectra Use cursor with keys Shift Ctrl and Alt you can change position and scale of plot 49 SUPPLEMENT 17 Calibration of Frequency Analyzer Frequency dependencies of output signal at fixed power of input signal measured during the calibration procedure are presented on the plot below Upper curve corresponds to input power of radio signal 2 mW Each curve corresponds to a power decreasing on 3 dB by means of an external mechanical attenuator Sensitivity at various input powers with step 3 dB INL NE IARI TE ET ETT TTT ALIA ETE TT TT TTT TT EET AA TELAT EE ET ALL VIN AN VIN LELUN dope Een YE
6. Power Level and Fixed Freguency Mode without Amplitude Modulation through GPIB e Step 6 Set Internal Frequency Control mode Read Status String If bit 7 of 7 byte is clear it means that the device is installed in Internal Frequency Control mode and you should go to step 7 4 activate local menu Control if bit 7 is set F set Internal Frequency Control Please pay attention that each of sending symbol F leads to switching between External Internal Frequency control mode q abort local menu Control and return to main menu Read Status String Once more one should check bit 7 of 7 byte Frequency Control in Status String e Step 7 Set Internal Power Control mode Read Status String If bit 6 of 7 byte is clear it means that the device is installed in Internal Power Control mode and you should go to step 8 4 activate local menu Control If bit 6 is set set Internal Power Control Please pay attention that each of sending symbol A leads to switching between External Internal Power control mode q abort local menu Control and return to main menu Read Status String Once more one should check bit 6 of 7 byte Frequency Control in Status String e Step 8 Set Internal Amplitude Modulation OFF Read Status String to check the current operation mode If 3 bit of 7 byte is set it means that the device is installed in Internal Amplitud
7. Saki small akin likeme iile lll 45 6 HOW TURN ON THE ANALY ZER essin leli Pate tapes prete 46 CASS RY ALES d DRE 46 DEUS cus MEMEN N RES N Rush hii anna fabas YEM UE 47 D MEASUREMENT E aisi etidm attese e EIE 49 SUPPE LL Calibration 50 18 FunctionalSchemeoffreguencyAnalyzer 5 9 AVIBGO WS K R R K a MAR Mr LEE PIE 52 43 1 GENERAL REMARKS 1 1 When millimeter wave applications came into many domains of human activity a need for precise measurements of signal frequency spectrum has become critical This need is quite understandable when for example it concerns to exploring extraterrestrial radio sources or micro mm wave background emission radio astronomy measuring chemical composition of the atmosphere through the molecular emission of different its components plasma diagnostics or many military applications Moreover in some cases the spectrum measurements have to be implemented in the real time scale For example the high temperature plasma physics research is just the case because of short plasma life time in experimental devices and poor plasma parameter reproducibility from discharge to discharge also it is important for plasma feedback control purposes As well the real time spectrum measurements are very needed in electronic warfare applications such as object r
8. button Menu 12 to abort local menu Control and return to main menu After that Generator will provide amplitude modulation with frequency of the triggering signal F External Power Control mode In this mode an external positive voltage 0 10 VDC controls output power of Generator Turn on the Generator as directed in part 8 Set output frequency as described in par A or B Set External Power control mode of Generator One should check LED External on the button Power Control 14 If LED glows it means that the device is installed in External Power Control mode If LED not glows one should go to position Control of menu pressing key 4 on keyboard Press button Frequency Control to switch on LED on the button 14 To abort Control presses key Menu Feed the positive 0 10 VDC voltage into the plug Input 15 External Power Control The higher voltage corresponds to the higher output power G External Frequency Control mode In this mode an external positive voltage 2 8 VDC controls output frequency of Generator Turn on the Generator as directed in part 8 Set output power as described in par A oet External Frequency control mode of Generator One should check LED External on the button Frequency Control 14 If LED glows it means that the device is installed in External Frequency Control mode If LED not glows one should go to position Control of 10 menu pressing key A o
9. higher output frequency H Save and or load were saving currently settings through GPIB bus Save current settings in program No 5 and load settings from program No 8 Save current settings in flash memory g activate main menu if it is needed 7 activate command Save Pr from main menu 5 save settings to program No 5 Load settings from flash memory g activate main menu if it is needed 8 activate command Load Pr from main menu 8 load settings from program No 8 J Set device address on GPIB bus GPIB interface card integrated into Controller is initialised automatically in device slave mode One can set Generator s address on GPIB bus from 01 till 20 Generator saves GPIB address in flash memory and installs it automatically after restart oet new GPIB address for example 5 assuming that present address is 14 9 activate menu of GPIB address setting Q 5 set new address 5 Address 5 will be installed after the sending of 5 within few seconds After that one have to communicate with device using the new address K Set regimes of the Receiver through GPIB bus For example for setting Application 100 one should to send symbol E For switching ON OFF the Harmonic Generator one should to send symbol T 17 SUPPLEMENT 1 Front panel of the Generator al Ek Posee Amplitude Modulation Menu
10. power 10 is recommended it is the default level at switching the Generator on Run sweeping 5 Run the SPECTRUM program The upper toolbar left and right panels should be displayed on the PC monitor Ensure that everything is nominal 6 Switch the Harmonic Oscillator on gently open LO attenuator so that the calibration mark was not less than 0 2 V T Perform the calibration Switch the Harmonic Oscillator off 48 9 10 11 12 15 D E F Let the external signal be applied to the Analyzer Gently open RF attenuator to obtain an acceptable amplitude of the measured signal 0 1 to 5 V Use the Autolock option if wish Set number of spectra to be stored on the PC disc in the Archive number line on the left panel of the SPECTRUM screen Enable the File option and complete data saving During for saving Data please don t use anything additional software for excepting to appear breakpoints in save Data Both the frequency resolution and the frequency measurement accuracy may be improved if the operational regime of Lens 8 GHZ is used see Section C of the G4 143 Manual 1 Close the RF attenuator 2 Determine the central Lens frequency denoted as fixed frequency in Section B of the G4 143 Manual so that the analyzed signal together with two adjacent calibration marks were within the Lens frequency band fixed frequency 4 GHz 3 Set
11. programming This program is placed on flexible diskette and contains a example of programming on Pascal language program sample pas uses dos crt include standart units SL ITFA88TP OBJ load interface function ITFA88TP INC include function declaration var dev i integer 00 ch Ghar const port 28 GPIB card address myadr 1 bufflen char 100 procedure SendCharToGPIB Ch char begin barrel writeln ibwrt dev buff Delay 10 end t 4 procedure 5SendStrzngroGPIB lnputotrzng istring var 1 lt Word begin tor eo byte lnputstrzuglol end b begin do SendCharToGPIB InputString l1 writeln GPIB device address readin dev read device address buff 0 bufflen i ibtout l000 clear buff initialisation set timeout HH e clear inteface repeat writeln Enter next regim 1 Initial Freguency wrrtelni 2 Frequency writeln Sweep Time writeln 4 Power Level writeln 5 Switch Ext Int Frequency Control writeln 6 Switch Ext int Power Control writeln 7 Start Sweep writeln OQ Shoo writeln 9 Read Status String writeln Qi c Ekime Ch Readkey case Ch of SI es begin case of 1 SendcharToGPIBE C L 55 to local menu SendCharToGPIB 1 to initial frequency set up delay 3000 S
12. pulse generator should be applied to corresponding plug 1 16 for the triggering of External Amplitude Modulation mode Button Reset restarts built in microcomputer 4 Button Menu calls operation menu to LCD 12 On the rear panel of generator the following controls are installed see Supplement 2 GPIB for connecting the Generator to GPIB bus 22 Operating Time counter 21 Fuses 24 and 25 Ground socked 23 Power Plug AC 220V 26 High Voltage Monitor output plug 27 intended for an external checking up the frequency of the oscillation Dependence of High Voltage Monitor output voltage versus frequency of oscillations is supplied in Supplement 8 Strobe FM signal output plug TTL 29 Strobe AM signal output plug TTL 28 BWO is a heart of the Generator Electrical Scheme of BWO is presented in Supplement 9 The Generator is functioning properly if the following conditions are met e When turning on the power the current spikes must be restricted e BWO control electrode voltage should appear if only deceleration voltage is present and must be switched off in the opposite case e BWO control electrode voltage must not be higher than 237V BWO is a source of UHF oscillations which a voltage of the decelerating system Anode Voltage controls frequency and output power is controlled by a voltage applied to the control electrode BWO is connected in a grounded cathode cir
13. q to stop sweep and return to main menu B Set Fixed Frequency through GPIB bus For example to set the initial frequency 165 121 GHz and fine adjust it one should to send symbols sequence Set Internal Frequency control mode See par 11 A above Set Internal Power control mode See par 11 A above oet Fixed Frequency 3 activate Manual local menu q 6 5 1 2 1 print frequency value on LCD bb 77 enter Fine adjustment of Fixed Frequency P to decrease fixed frequency one smallest available step left to increase fixed frequency on one smallest available step right Abort setting of Fixed Frequency 66 2 77 q return to main menu C Set Zoom Frequency Window mode through GPIB bus For example to set the zoom window width 1 0 GHz and start sweep one should send symbols sequence Set Internal Frequency and Power control as described in par 11 A Set Power Level as described in par 11 A Set Fixed Frequency as described in par 11 B oet Zoom Frequency Window width D activate local menu Zoom 3 set zoom width 1 0 GHz Start the sweep 6 start sweep Stop the sweep q stop sweep D Set Internal Amplitude Modulation mode through GPIB bus Square wave 100 amplitude modulation with frequency 1 kHz is provided in this mode Set fixed frequency and power level as described in par 11 A 11 B Set Internal
14. sweep in the vicinity of fixed frequency See par B User would program zoom window width 0 25 0 5 1 0 or 2 0 GHz power and time of sweep The sweep is provided by saw tooth voltage Control Unit provides linear increasing of control voltage during Sweep Time and then fast voltage decreasing during approximately 1 ms time Pay attention that the sweep is provided by linear increasing control voltage sweep frequency range is small and linear approximation of the frequency dependence versus control voltage is taken into account within zoom window Tum on the Generator as directed in part 8 Set Internal Frequency and Power control as described in par A Set the desired power level as described in par A Set the desired fixed frequency as described in par B Press key 5 on Digital Keyboard 8 to activate local menu Zoom oet the desired zoom window width using the following command from the local menu 1 0 25 set zoom width 0 25 GHz 2 0 50 set zoom width 0 5 GHz 3 1 00 set zoom width 1 0 GHz 4 2 00 set zoom width 2 0 GHz Press one of four keys from 1 to 4 Generator sets zoom window width and returns automatically to main menu To start the sweep one should press key 6 on Digital Keyboard 8 Generator will indicate initial and final frequencies of sweep calculated using linear approximation and start the sweep At the beginning of each sweep Generator produces TTL strobe pulses Use Strobe Signal output
15. to turn on the generator and indicator Power to indicate condition of generator Liquid Crystal Display for indication of various regimes of Generator 5 Tuning knob for frequency and power setting 6 Two buttons for fine setting of frequency or power 7 Digital Keyboard 8 Functions Keyboard 11 14 Button Power Control 14 switches External or Internal Power Control modes If LED on the button is glow it means that External Power Control mode is switched on In External Power Control mode 0 10VDC control voltage should be applied to the corresponding socket Input 15 for a remote electrical manipulation of output BWO s power In Internal Power Control mode the power is controlled by microcomputer using DAC Button Frequency Control 11 switches External or Internal Frequency Control modes If LED on the button is glow it means that External Frequency Control mode is switched on In External Frequency Control mode 2 8VDC control voltage should be applied to the corresponding socket Input 10 for a remote electrical manipulation of output BWO s frequency In Internal Frequency Control mode the frequency is controlled by microcomputer using DAC Buttons Amplitude Modulation 13 switch on different modes of amplitude modulation CW OFF button Internal 1 kHz Amplitude Modulation Internal button Amplitude Modulation with External Triggering External button TTL signal from an external
16. 1 5 1 at the 1 mW output power 3 12 Output waveguide WR 06 3 13 Waveguide flange UG 387 U M 3 14 Internal square wave modulation frequency kHz 1 3 15 External square wave modulation frequency kHz 1 100 3 16 External Power Control Voltage V 0 10 3 17 External Frequency Control Voltage V 2 8 3 18 Operating modes CW Remote frequency and power regulation by an analogue voltage frequency and power regulation from front panel and GPIB interface 3 19 Electrical resistance between primary power line and the cabinet is no less than 100 MOhm at high humidity no less than 3 MOhm at high temperature no less than 5 MOhm 3 20 All parameters mentioned above are valid after 30 min warming up period 3 21 Power consumption is no more than 400 VA 4 RELIABILITY 4 1 Main time to failure no less than 2000 h 4 2 909 life time no less than 2 years 5 CONSTRUCTIVE PARAMETERS 5 1 Dimensions 495x180x480 mm 9 2 Weight no more than 23 kg 6 PRINCIPLE OF OPERATION Generator is made up of the oscillator unit control unit modulator unit and power supply unit Supplement 3 Oscillator unitis made up of BWO and high voltage isolator BWO intended to generate UHF oscillations High voltage isolator intended to isolate the BWO s cabinet being kept under high voltage from grounded output waveguide Control unit is based on PC microcomputer It is used together with digital to analogue converter as triang
17. 46 Robezu str LV 1004 Riga Latvia Fax 371 7 065102 Mm wave Division in St Petersburg Russia Fax 7 812 325 58 56 Tel 7 812 325 58 58 ext 316 E mail korneev exch nnz spb su Real Time Frequency Analyzer 120 180 GHz Part No RTA D 180 Operation manual 2nd edition 10 05 2000 Operation manual Containts Millimeter Wave Generator l Heterodyne Receiver 34 Real Time Analyzer 43 Millimeter Wave Generator G4 143ga User Manual Contents L GENERAL RENLARK S a elena allak melekle 2 2 AMBIENTAL CONDITIONS tiec uo eR dee al eee 2 PARAMETERS lg alm diil nO okla 2 PE e GA Eu Ye A EK E MM 3 5 CONSTRUCTIVE 3 6 PRINCIPLE OF OPERA FI N x kle I sandalla si 3 OPERATION N NO ATE aa a ba Maiores eiue ete ub dl 6 8 HOW TO TURN ON THE GENERATOR eese 6 9 PURSUANCE 0 enne 6 GPIB INTERFACE 12 11 AN EXAMPLE OF OPERATION USING GPIB INTERFACE 13 SUPP IEMET S er E 19 l Front panel ofthe CI ne 19 2 Reat panel or tne Generator eisean an a dalan E A sad 20 3 Disposition of the units in the Generator sss eene 21 4 Block diagram OF UML samara le Delon 22 5 Lhe structure or the calibr
18. ANALYZER To switch on the entire device one should to do the following 6 1 Connect devices according the scheme presented on Supplement 18 Numbers of plugs are mentioned on the scheme according User Manual for Generator and Receiver For connection between the Generator and the Receiver use applied special cable and waveguides 6 2 Switch on all devices according User Manuals 7 PRIMARY TEST 7 1 Turn on the Analyzer as directed in part 6 7 2 Apply video signal from plug 34 on the Receiver to oscilloscope 7 2 Set on the Generator the following parameters Fini 2 118 00 GHz Ffin 181 00 GHz Sweep Time 0 015 Output Power 10 7 3 Switch On the Harmonic Generator for that press button 35 on front panel of the Receiver If LED on button is glows it means that the Harmonic Generator is working 7 3 Run Sweep on the Generator 7 4 Open the LO Variable Attenuator 7 5 You must to see a picture on the oscilloscope is presented below 1 11 12 Time ms 46 8 Software As it has been mentioned above the Analyzer may be controlled manually with aid of the Front Panel controls or externally via PC Remote Control function using data acquisition cards PCI 1800 and PCI 488 as the hardware Following minimum system requirements have to be met Pentium processor 300 MHz RAM 64 MB a vacant RS 232 serial port two available PCI slots PC is operated under Windows 95 The specific PC software is delivered written on CD It cons
19. Amplitude Modulation mode 15 Read Status String to check the current operation mode If 4 bit of 7 byte is set it means that the device is installed in Internal Amplitude Modulation mode 4 activate local menu Control if 4 bit of 7 byte is clear switch on Internal Amplitude Modulation mode Read Status String Once more one should check 4 bit of 7 byte Internal Amplitude Modulation in Status String 66 2 77 q return in main menu E Set external positive pulse modulation mode through GPIB bus oquare wave 10090 amplitude modulation with frequency of an external triggering source is provided in this mode e Setthe frequency and power level as described in par 11 A 11 B e Set External Amplitude Modulation mode Read Status String to check operation mode If bit 6 of 7 byte is set it means that the device is installed in External Amplitude Modulation mode 4 activate local menu Control if bit 6 of 7 byte is clear switch on External Amplitude Modulation mode Read Status String Once more one should check 6 bit of 7 byte External Amplitude Modulation in Status String g return to main menu e Feedthe 5 V TTL positive pulses with a frequency in the range 1 100 kHz and duty ratio 2 square wave into the External Triggering Plug 16 F Set External Power Control mode through GPIB bus In this mode an exter
20. CK DIAGRAM OF THE RECEIVER 15 ELECTRICAL SCHEME OF KEYBOARD AND POWER SUPPLY 35 35 36 37 38 39 40 41 16 ELECTRICAL SCHEME OF AMPLIFIERS AND VIDEO DETECTOR 42 34 Heterodyne receiver Technical description and user manual 1 Technical parameters Frequency Range GHz Input waveguide Waveguide Flange Range of Input Signal Power mW set by RF Variable Attenuator IF Bandwidth MHz Output Video Signal V Input Voltage V Calibrator Frequencies GHz Calibrator Stability Output power long term stability 90 Dimensions mm 120 180 WR6 UG 387 U M 0 001 1000 4 16 5 0 5 100 220 VAC 50 Hz N 20 30 N 6 1 ppm 5 490x360x140 2 Design and principles of operation The functional scheme of the receiver is presented below Power Suppliers Amplifier and Video detector Output Figure 1 The receiver consists of Directional Couplers 10 dB DC1 DC2 Variable Attenuators 0 30dB Broadband Isolator Broadband Detector BD Harmonic Generator Harmonic Generator Signal RF 4 Variable Attenuator Variable Attenuator GENERATOR LO IF Preamplifier Amplifier and Video detector Power Suppliers 35 The first directional coupler is used to apply local oscillator frequency LO and input radio frequency RF signal to the detector that is used in mixer mode The second directional coupler is used to apply signal from harmonic generator to the detector After
21. ENT 4 Block diagram of the control unit GPIB Mouse port Mother External SVGA display Board with SVGA LPT External keyboard LC Display ISA Device Bus Keyboard Grid B converter source DAC 2 Frequency control Anode voltage voltage DAC 3 converter source DAC 4 A simplified block diagram of the Computer Unit is shown on the plot It includes Mothers board Juky 730 Industrial Standard PC compatible microcomputer There are four digital to analog converters in two data acquisition cards ACL 8112 DAC1 sets the amplitude of power control voltage DAC2 sets the amplitude of frequency control voltage It is used for full band sweep DAC3 sets the amplitude of frequency control voltage in Zoom Sweep Window mode DAC4 sets the reference voltage for DAC3 It allows change width of frequency window in zoom sweep mode The device operates as follows Built in microcomputer and data acquisition cards provide voltage for power and frequency control DAC1 is used for the regulation of voltage applied to control electrode grid of BWO and so for the control of the output microwave power DAC2 is used for the regulation of voltage applied to anode of BWO and so for the control of the output frequency Control voltage is constant in Fixed Frequency mode or triangle linear rise voltage in Sweep Frequency mode DAC3 is used in Zoom Sweep Window mode A constant voltage from DAC2 is added to triangle linear rise voltage produced
22. R INSANE d RE ES C o B O D SN AA A JJ LL MAAST ALAN LL 22 p i ii PE Hi sere PAA ALN Specially designed RF source with fixed output power was used An electric attenuator supported constant output power 2 mW in frequency region from 120 till 180 GHz Power Level of Generator LO was 10 LO and RF Variable Attenuators were opened Generator sweeps with time 40 mS Amplitudes of output signal are presented on the diagram It is important to note that the presented sensitivity of the Receiver is valid only if LO and RF Variable Attenuators are opened If one will apply another LO power the sensitivity will be changed accordingly Calibration data are supplied on flexible disk in Excel format file CalReceiver xls 50 SUPPLEMENT 18 1 Functional Scheme of Frequency Analyzer SYNC CONTROL Generator RF Input 4 GPIB PCI 1800 L Data Acquisition Card SYNC Output Video Signal CON3 pin1 PCI 488 Data Acquisition Card 2 Waveguide s connection between the Generator and the Receiver 51 Es Spectrum 117 84 197 27 GHz Hesolution 148 1 MHz gt Spectrum 117 84 187 27 GHz Time 0 01 18 1 MHz Sweep Remote Calibration Esi FLA Supplement 19 Fig 2 HETERODINE RECE VER a
23. ation files io er E att ER HERE EHE at ba b s 23 6 The diagram of the Control Voltage and nn 24 Te Output power Versus Trequeltic eae ias etes e Lec tont olaran Ces 25 8 Frequency versus Control voltage Frequency versus High voltage monitor 26 9 BlectticabschemeobBWOJLTUbe c eb Oa ven al animal du RU 24 LOL Example or DEOPEAUBEDHITIE ada pel 28 11 Step by step instruction Setting Power Level and Fixed Frequency 30 1 GENERAL REMARKS 1 1 Microwave generator G4 143ga hereinafter called Generator is intended to be used as a signal source in the millimetre range of wavelengths for tuning and adjustment of the radio electronic device 1 2 The Generator may be used in laboratory conditions 2 AMBIENTAL CONDITIONS Conditions operations temperature 5 40 C relative air humidity up to 95 at the temperature 30 C primary power AC 220 10 V 50 0 5 Hz atmospheric pressure 84 112 kPa Some abbreviation used hereinafter BWO Back Wave Oscillator VSWR Voltage Standing Wave Ratio CW Continuous Wave OA Operating Amplifier LCD Liquid Crystal Display 3 PARAMETERS 3 1 Frequency range is 120 180 GHz Device has a reserve more then 1 at the edges of the range 3 2 Full band sweep time less then 200 microseconds with external frequency control 10 milliseconds with internal frequ
24. by DAC3 Output voltage of DAC3 is divided on coefficient 1 20 DACA controls amplitude of Zoom Sweep Circuit switches between various modes are provided by relays Parallel port LPT1 is used for control of liquid crystal display LCD RS 232 serial port COM3 is mouse port It serves the operation of tuning knob 23 SUPPLEMENT 5 The structure of the calibration files The structure of the file We calibrate the output frequency of Generator through DAC2 See Supplement 4 We change DAC code from 0000 till OFFF and measure output frequency at 100 Power Level Maximum Power Level 100 corresponds to code OFFF DAC1 Measured results are presented in file frequen dat This file is stored in flash memory of Control Unit Example There are 4096 strings in the file Each string presents the frequency in GHz Data presented at the first string corresponds to DAC2 code 0000 The code is increasing on 1 with increasing of string number For example DAC2 code 0006 corresponds to output frequency 117 08 GHz 116 96 116 99 117 00 117 03 117 06 117 08 24 SUPPLEMENT 6 The diagram of the Control Voltage and strobes Uout F out Ustrob I The diagram of the internal triangle wave control voltage on plug 27 2 The diagram of the output frequency 3 The diagram of TTL output strobe signal on plug 29 T sweep time set by Digital Keyboard 8 or by GPIB bus command o strobe time durat
25. cuit In this case the output waveguide of the BWO as well as its cabinet has a high electric potential relative the Generator cabinet so the special high voltage isolator is used to isolate the BWOT s output waveguide from the Generator s cabinet Setting the proper voltage on the BWO decelerating system provides the setting of the Generator s frequency For this purpose the circuit is used which consists of the next parts e commutator e control unit e controlled high voltage source e BWO decelerating system Commutator provides a connection between control input of the High voltage power supply and external broadband frequency tune input 10 if External Frequency Control 11 is switched on Commutator provides a connection between control input of the High voltage power supply and control unit output if External Frequency Control 11 is switched off Control unit provides Linear control voltage with different full band Sweep Times 0 01 0 02 0 04 0 08 0 1 0 2 0 4 0 8 1 2 4 8 10 20 80 100 Sec in sweep frequency mode see Supplement 6 Fixed DC voltage in fixed frequency mode There are two possibilities of the Control unit programming Manual control using front panel controls Remote control using GPIB bus Built in microcomputer serves an indication of Initial and Final frequencies on the LCD display 5 The computer calculates corresponding frequency from the code of DAC that serves frequ
26. e option If the Remote option is enabled the Remote screen is displayed on the right panel of the PC monitor image Fig 2 Sup 19 It simulates Front Panels of the Heterodyne Receiver and the BWO Generator The Analyzer may be controlled and the operational regimes are chosen with pressing the buttons on the screen in the same way as it has been described in the previous part of the Manual simulated on the screen LCD exhibiting the same communications as the display on the Generator Front Panel Sweep option If the Sweep option is enabled the Sweep screen is displayed on the right panel of the PC monitor image Fig 1 Sup 19 It consists of two amplitude V vs frequency GHz graphs The upper one Last sweep represents spectrum of the measured signal obtained during last individual heterodyne sweep The lower one Summary sweep is the spectrum averaged over the number of sweeps set on the left panel in the Summary number window Autolock option here and in Calibration see below if enabled shows white vertical mark which stands at the centered signal frequency Its digitalized value in GHz is seen in the Autolock window Calibration option This option is operated when the Calibration Harmonic Generator is switched on with pressing the Harmonic button on the Receiver Front Panel and the frequency window is chosen with setting the lower and upper sweep frequencies of the Generator If the Calibratio
27. e Modulation mode and you should go to step 9 32 SUPPLEMENT 11 A activate local menu Control if 3 bit of 7 byte is clear D switch on Internal Amplitude Modulation OFF mode Symbols D and B C define Amplitude Modulation Mode one valued Read Status String Once more one should check 3 bit of 7 byte Internal Amplitude Modulation in Status String 11 5 q abort local menu Control and return in main menu e Step 9 Set Fixed Output Frequency For example to set the fixed frequency 135 121 GHz 3 activate Manual local menu Wait few seconds 3 5 172 1 print frequency value on LCD e enter Fixed frequency should changed Abort setting of Fixed Frequency 11 5 q return to main menu e Step 10 Set Power Level For example to set the Power Level 100 000 1 enter to local menu Set Up 4 enter to local menu Power lvl Wait few seconds 1 0 0 0 0 print power level on LCD e enter Output power should changed 11 7 q return to local menu 11 5 q return to main menu 33 Heterodyne receiver Technical description and user manual Contents 1 TECHNICAL PARAMETERS 2 DESIGN AND PRINCIPLES OF OPERATION 3 PRINCIPLES OF UNITS OPERATION 4 CONTROL SUPPLEMENTS 12 FRONT PANEL OF THE RECEIVER 13 REAR PANEL OF THE RECEIVER 14 BLO
28. e of 3 to local menu to sweep time set up Please wait Sweep time 0 01 s Enter to local menu to main menu case 3 case of 4 to local menu to power level set up Please wait power level 71 Enter to local menu to main menu case 4 case of 5 to control menu Switch ext rnt requency control to main menu case 5 case of 6 to control menu switch ext int power control to main menu case 6 receiver data 13 then buff i 32 30 SUPPLEMENT 11 Step by step instruction Setting Power Level and Fixed Frequency Mode without Amplitude Modulation This supplement describes how to set Power Level and Fixed Frequency mode without Amplitude Modulation using device keyboard steps 1 5 and trough GPIB interface steps 6 10 e Step 1 Set Internal Frequency control mode One should check LED External on the button Frequency Control 11 If LED not glows it means that the device is installed in Internal Frequency Control mode and you should go to step 2 If LED glows one should run command Control of menu pressing key A on keyboard Press button Frequency Control to switch off LED on the button 11 To abort Control menu presses key Menu e Step 2 Set Internal Power control mode One should check LED External on the button Power Control 14 If LED not glows it means that the device is installed in Internal Power Control mode a
29. ecognising or electronic countermeasures to millimeter wave weapons However real time broad band analyzers with direct frequency spectrum measuring continue to be a rare bird in catalogues of leading world manufacturers of mm wave products ELVA 1 DOK Ltd fill this need for the frequency range of 120 to 180GHz with their device 1 2 The Anlalizer may be used in laboratory condition 1 EXPLOITATION Conditions operations temperature 5 40 C relative air humidity up to 95 at the temperature 30 primary power AC 100 220 10 V 50 0 5 Hz atmospheric pressure 84 112 kPa 2 PARAMETRES 3 1 Frequency range of the input signal spectrum GHz 120 to 180 3 2 IF Bandwidth MHz 4 16 5 3 3 Basic frequency resolution MHz 12 5 3 4 Maximum frequency resolution kHz 61 3 5 Minimum time of the spectrum analysis ms 10 3 6 Minimum time of single frequency measurement ms 0 0024 3 7 Power of the input signal mW 1 to 1000 3 8 Calibrator Frequencies GHz N 20 30 N 6 3 9 Calibrator Stability 1 ppm 3 10 Output power long term stability 5 3 11 Voltage of the output video signal V 0 to 5 3 12 Input waveguide WR6 3 13 Input waveguide flange UG 387 U M Operational modes e spectrum measurement during a single sweep e measurement of the spectrum averaged over several sweeps visualization of the spectra on the IBM PC monitor with e real time spectrum measurements with continuously repeated sweeping and accumulating the outp
30. ency control 3 3 Admissible variation of the frequency of unmodulated oscillation if primary power voltage changes up to 10 for 50Hz is no more than 0 05 3 4 Relative variation of frequency of the output signal is no more than 1074 if the load VSWR changes from 1 1 to 1 3 at the output power 1mW Output power should be installed using an external attenuator 3 5 Limit of instability of the frequency of unmodulated oscillations at the unchanged primary power voltage during any 15 min of work is 0 0196 the warm up time after adjustment from one frequency to another must be no less than 5 min 3 6 50 Hz deviation of the frequency of the CW output signal is no more than 0 002 in the mode with the frequency control by means of an external voltage 3 7 Guaranteed power level of unmodulated oscillations is no less than 40 mW at the load VSWR no larger than 1 3 within frequency region 120 180 GHz 3 8 The limit of instability of the output power level of unmodulated oscillation at the unchanged environment and primary power voltage during any 15 min of work is 0 3dB the warm up time after adjustment from one frequency to another must be no less than 5 min 3 9 Admissible variation of output power level of unmodulated oscillation at slow 10 variation of primary power voltage for AC 50Hz is no more than 0 5dB 3 10 50 Hz AM level of output CW signal is no larger than 196 3 11 VSWR of output of the Generator is no more than
31. ency control using a calibration file frequen dat Please refer to supplement 5 This file contains 4096 lines Each line presents frequency at maximum output power corresponding digital to analogue converter code from 0 till 4095 At smaller output power the operation frequency is shifted a bit from the position corresponded to the maximum output power Frequency shift between values at maximal and minimal power is about 1 GHz Frequency shift is calculated by formula and used by microcomputer for indication of actual frequency For example initial and final frequencies of the sweep indicated on LCD are calculated this way Operating regime of the Generator is defined by BWO control electrode voltage grid In the CW regime this voltage is constant In the Internal or External Amplitude Modulation regimes this voltage is also symmetric rectangular pulse sequence with amplitude equal to the constant voltage in CW regime In the External Power Control regime the voltage is user defined In all regimes voltage applied to BWO control electrode must not exceed 237V The operating regime of the Generator is defined by a joint functioning of the next parts of the device e Operating regime switch e Modulator e 5 23 V controlled voltage source e BWO control electrode The BWO current overload protection circuit receives the signal proportional to the decelerating system current When this current is larger than 50 mA the circuit comes in
32. endStringroGPIB 55 senacharroocbIB e Please wait 00 initial frequency 55 00 GHz Enter 29 e E Vm cs TH T m6 de end until Ch end SUPPLEMENT 10 SendCharToGPIB q SendCharToGPIB q end begin SendCharToGPIB l SendCharToGPIB 2 delay 3000 oendStrringrToGPIBXIX 56 00 SendCharToGPIB e E lt SendCharToGPIB SendCharToGPIB end q e begin SendCharToGPIB l SendCharToGPIB 3 delay 3000 SendStringToGPIB 000 01 SendCharToGPIB e 2 SendCharToGPIB SendCharToGPIB end q gi begin SendCharToGPIB l SendCharToGPIB 4 delay 3000 oendStrrngroGRIB 071 0091 5 SendCharToGPIB e 2 SendCharToGPIB SendCharToGPIB end q eu begin SendCharToGPIB 4 SendCharToGPIB F SendCharToGPIB q end begin SendCharToGPIB 4 SendCharToGPIB A SendCharToGPIB q end SendcharTrToGPLBItt2 ys SendCharToGPIB q begin case of buff 0 bufflen i ibrd dev buff writeln Exit code for 1 1 to 100 do writeln Receive string Write ln out end gre U oM gi bur lr to local menu to main menu case 1 case of 2 to local menu to final frequency set up Please wait final frequency 56 00 GHz Enter to local menu to main menu case 2 cas
33. erator Generator is indicated in pin 5 1 OFF VON Video detector U2 U3 D1 D2 detects IF signal then it is amplified by Video Amplifier The Video Amplifier is based on U4 There are added negative synchronisation pulses to the output video signal It is received from the Generator through plug Generator 38 pin 9 The circuit D3 D4 R21 adds these pulses to output video signal Power supply consists of transformer and integrated circuits The scheme of power supply is built on typical elements see Supplement 15 Keyboard plate provides control signals for setting gain mode and switching ON OFF the Harmonic Generator see Supplement 15 There is a possibility to control a condition of the Receiver The Keyboard plate provides static TTL signals which are applied to Generator plug 38 36 Correspondence between values of signals and condition of the Receiver are shown in the next table Signal Value Gain 10 switch ON OFF Gain 1000 switch ON OFF Gain 100 switch ON OFF Harmonic Generator switch ON OFF Relays plate applies 12V and 24V to the Harmonic Generator for turning on it They are controlled TTL signal from Keyboard plate see Supplement 14 4 Control List of controls situated on Receiver front and rear panels are presented in the following table Name Position on Descriptions Comments Rear panels Switch on off When the receiver is oower suppl turned on LED lights Harmonic Front
34. f the table must coincide The calibration procedure should be performed after every operational regime reset One of the most typical causes for the frequency deviation from its calibrated value is temperature variation in the Analyzer Usually 10 to 15 min after the reset are taken before the steady state is attained Repeated checking the frequency is recommended if no frequency drift is the case values in both the rows Fix and Found will be equal some additional instruments to change the plot resolution are collected at the right side of the panel They allow fitting scales of the coordinate axes to the maximum signal amplitude and or to the full frequency band Another group of options will enlarge an area of X or Y axis or both into the full scale plot A third tool will zoom continually an area pointed with the mouse driven cursor File option The File option when enabled proposes a menu to choose one of two possible formats for saved data file text format or archive The text file is to be analyzed with Microsoft Excel and the archive file should be imported into the 3DVIEW program module Fig 4 Sup 19 9 Measurements 1 Close both LO and RF attenuators in the Heterodyne Receiver Connect the input signal waveguide to the RF input of the Receiver 2 Switch the Analyzer on according to Section 6 of the Manual Let it warming up for 30 min 3 Set desired sweep parameters and the output power of the Generator the
35. ion about 0 001 sec 25 SUPPLEMENT 7 Plot 1 Dependence of Output Power versus frequency by various Power Levels Output Power vs Frequency 130 e EESTI IEEE IE Power Level not LL LL LLL LL LL LL La AL A A A mt Auraria An L L N LR IA IERI LY VN AL so MT T RAJ SE 75 so LL d E LLL LL LLL LI LLL LLLA LR LA la LT ES of Ld LAAN ARAL A TALES EQ sa so REPRE PET TT RAM TTT TE TE ETE PESE of ee of FT TTT TTT Ty 388RASRESESBSSSSSSESHHSJSS Frequency GHz 25 The structure of the calibration data The data in the calibration files are placed in ten columns divided by the tabs Uinp Hm P25 F25 250 Fso PTS Frs 100 F100 2900 3281 1030 117 74 3340 117 26 4960 116 99 5790 116 96 2 900 3 281 10 30 117 74 33 40 117 26 49 60 116 99 57 90 116 96 The first column Uinp is a control voltage in V applying to the external broadband frequency input 10 see supplement 1 The second column HVm is a voltage in V measured on the HV Monitor output plug 27 see supplement 2 corresponding to the data placed in the first column The third column P25 is measured output power of Generator in mW at 25 power level corresponding to the data placed in the first column The forth colu
36. ists of program exe modules and an installation file The program modules have been composed in the LabView standard and using its libraries To enable the Remote Control function one should run the program SPECTRUM on PC It will perform choosing operational regimes frequency calibration of the Analyzer and analogue to digit conversion storage and visualisation of the data obtained Another software component program 3DGRAPH is used for representing the spectra measured in three dimensional axonometric projection Once the SPECTRUM is run an image Fig 1 Sup19 is displayed on the PC monitor consisting of upper toolbar with File Sweep Remote Calibration and Exit options left and right panels The left panel has the ELVA 1 logo above list of Options in the middle and the Message log below The Remote screen is displayed first on the right panel just after running the SPECTRUM In the Options the line GPIB address denotes logical number of the Analyzer in the GPIB interface Summary number is number of sweeps used for obtaining averaged spectrum Archive number defines number of spectra to be stored on the PC disc after completing the File option In the Noise level line a voltage is determined in Volts that will be considered as the lower limit when searching for calibration signals see subsection Calibration below Message log describes last ten operations implemented by the SPECTRUM Remot
37. l menu Control and return to main menu Read Status String Once more one should check bit 7 of 7 byte Frequency Control in Status String e Set Internal Power Control mode Read Status String If bit 6 of 7 byte is clear it means that the device is installed in Internal Power Control mode 4 activate local menu Control If bit 6 is set A set Internal Power Control g abort local menu Control Read Status String Once more one should check bit 7 of 7 byte Frequency Control in Status String e Set initial frequency 1 activate Set Up local menu 1 enter in local menu Fr intl 17 2 5 4 5 6 print frequency value on LCD 66 77 enter 6 7 q return to local menu e Set final frequency 2 to enter in local menu Fr 1 9 6 9 8 7 print frequency value on LCD 66 77 enter 6 2 77 q return to local menu e Set Sweep Time 9 enter to local menu Time Swp 0 Q 0 4 print frequency value on LCD 66 77 e enter 6 2 77 q return to local menu e Set Power Level 4 enter to local menu Power lvl 5 0 0 0 print power level on LCD enter 66 2 77 q return to local menu 6 2 77 q return to main menu 14 Start sweep 2 to start sweep 6 mI
38. l schemes of Keyboard and Power Supply 424V 3 OUT X36 D14 D17 LM7824 C22 X28 1 C21 1 220 Po D18 D21 OUT X35 LM7912 100 220VAC 12V giy OUT x34 2 1 7812 C30 X33 X32 X27 RELAY 10 KEYBOARD X26 10 to 64 143 10 fromG4 143 x16 RELAY 100 1 X25 X24 100 to G4 143 100 fromG4 143 i X17 x23 1000 toG4 143 1000 fromG4 143 X18 RELAY 12Vand 24V X22 HGoff on fromG4 143 X21 X19 HGoff on toG4 143 X20 5V SUPPLEMENT 16 Electrical schemes of Amplifiers and Video detector DETECTOR X6 12V R13 1 3k R16 1 3k INPUT 5 X6 R6 C4 4 510 n 1 R9 E 390 d b 100 d K1 R7 C5 C11 51 C7 R14 1 39 ao 390 R15 1 3k 390 1 R8 C6 2 db 5 1 3 9 K2 X7 GROUND A2 4 fi 2 A R24 R25 R26 R27 1k 1k 1k 1k X12 X13 OpGROUND OpInptu 100 Input 100 OpInput 10 Input 10 5V OUTPUT GROUND non M c EE STROBE X16 R21 1k N R18 1k 3 OUTPUT C12 R17 390 510 C40 3n3 X14 AMPLIFIER AND VIDEO DETECTOR 42 Real Time Frequency Analyzer 120 180G Hz Part No RTA D 180 User Manual Contains REMARK Sa on iode MES ERO cut aba dE AU al adi 44 GA Bl 44 ea ea e ete ilm a Al A dene D nC 44 b e ELBIE LEM A DEL 45 5 PRINCIPLE OF OPERA O lan
39. ld enter to main menu Press the button Menu 12 if it is needed Press key 8 on Digital Keyboard 8 to activate command Load Pr from main menu Choose number of set up from O to 9 pressing the corresponding key on Digital Keyboard J Set device address on GPIB bus GPIB interface card integrated into Controller is initialised automatically in device slave mode One can set Generator s address on GPIB bus from 01 till 20 Generator saves GPIB address in flash memory and installs it automatically after restart e Set new GPIB address for example 14 assuming that present address is 19 Press key 9 to activate menu of GPIB address setting On LCD screen appears text GPIB address 19 Set new Press keys 1 4 to enter new address 14 11 Address 14 will be installed after the pressing of second digit Controller will return main menu automatically after two seconds If one would like to install address 1 he should enter 0 1 in series K Test parameters of BWO tube This mode allows measure actual operating voltages and currents for BWO tube In Heating Current ii Uh Heating Voltage iii Anode Current Ug Grid Voltage e Press key on Digital Keyboard 8 to active Additional Menu e Please don t use Key 2 This is Service mode for the using of technical service staff only e Press key 1 to active Test e On LCD screen appea
40. le ___ Reime Bt Vawe _ Amplitude modulation External 0 0 Amplitude modulation Internal Amplitude modulation OFF Power External Control Frequency External Control Application 10 Application 100 Application 1000 Harmonic Generator ON OFF Finit describes the Initial Frequency in GHz Ffin describes the Final Frequency in GHz Time describes the sweep period in seconds CopyScreen contains 41 symbols displayed on LCD at the moment of the request 20 first of them correspond to the first string of LCD then CR symbol follows the next 20symbols correspond to the second string of LCD CR bytes are standard The main principle of Generator control using GPIB interface is to repeat the same sequence of commands as used in manual control mode 11 AN EXAMPLE OF OPERATION USING GPIB INTERFACE This part repeats par s A H of par 9 but only without comments 13 A Frequency sweep mode through GPIB bus For example one could set the follows Internal Frequency and Power Control mode Initial Frequency 125 456 GHz Final Frequency 136 987 GHz Power Level 5096 Sweep Time 0 04 S e Set Internal Frequency control mode Read Status String If bit 7 of 7 byte is clear it means that the device is installed in Internal Frequency Control mode 4 activate local menu Control if bit 7 is set F set Internal Frequency Control q abort loca
41. le wave voltage oscillator for digital remote control of generator from front panel or by means GPIB bus Power supply unit includes the following parts Controlled high voltage source for accelerating electrode of BWO Controlled 5 230 V DC voltage intended to feed the modulator and BWO control electrode DC 1 2 V voltage source intended to feed the BWO heater DC 16 and 16 V voltage sources intended to feed OA s DC 5 V voltage source intended to feed computer and relays BWO current overload protection circuit intended to switch off the high voltage transformer if load current of decelerator power supply is larger than 50 mA Control voltage overload protection circuit is intended to switch off the BWO control electrode voltage if deceleration voltage is lower than 300 V This circuit allows also the BWO control electrode voltage to be supplied if only the deceleration voltage higher than 300 V is presented on BWO s deceleration electrode when the Generator is being turning on BWO heater current overload protection circuit intended to limit the BWO heater current at the current spikes in the moment of Generator turning on High voltage indication READY 3 circuit intended for signalling if decelerating voltage source is switched on Modulator unit intended to modulate amplitude of output signal depending on operating mode On the front panel of generator are installed the following controls see Supplement 1 Button Power 1
42. led by the manufacturer using external calibrated mm wave source which imitates the input signal Result of the calibration is provided in form of the calibrating curves in the package with the device Supplement 17 Maximum spectral sensitivity of the device is defined by the minimum input signal power approximately 0 001 mW and intermediate frequency IF bandwidth of the receiver With the latter being equal to 12 MHz from 4 to 16 MHz it gives the maximum sensitivity to be equal to about 10 7 W MHz The sweep time for the whole frequency band can be varied within a wide range 10ms 20ms 40ms 4 8 s 10s 13 steps totally that defines the frequency sweeping rate to be equal respectively to 5 GHz ms 2 5 GHz ms etc The analyzer operates in two basic regimes At the first of them digital to analogue converter DAC of the generator produces 4096 conversions for the whole frequency band from 120 to 180 GHz It implies that frequency resolution at this regime is about 15 MHz which is the minimum one and corresponds to the IF bandwidth of the receiver Of course it is not obligatory to scan over the whole band user may narrow the band decreasing respectively the sweep time and increasing sweep repetition rate but the number of the conversions will be decreased proportionally keeping the same resolution At the second zoom or lens regime the user chooses a narrowed band 8 GHz 1 GHz 0 5 GHz or 0 25 GHz centred about a freque
43. mn F25 is a Generator frequency in GHz at 25 o power level corresponding to the data placed in the first columns The fifth column P50 is measured output power of Generator in mW at 50 power level corresponding to the data placed in the first column The sixth column F50 is a Generator frequency in GHz at 50 o power level corresponding to the data placed in the first columns The seventh and eighth columns P75 and F75 correspond output power and frequency at 75 power level corresponding to the data placed in the first columns The ninth and tenth columns P100 and F100 correspond output power and frequency at 100 power level corresponding to the data placed in the first columns 26 SUPPLMENT 8 Plot 1 Dependence of voltage on the HV monitor output versus frequency at maximum level of output power Frequency vs output voltage of High Voltage Monitor at 100 Power Level Frequency GHz High Voltage Monitor V Plot 2 Dependence of frequency versus control voltage applied to the external broadband frequency tune input 10 at maximum level of output power Frequency vs Input Control Voltage Frequency GHz Input Control Voltage V 27 SUPPLEMENT 9 Electrical Scheme of BWO Tube Anode is Millimeter Wave anode Output O E P O Cathod Uheating Uanode 500VDC 2500VDC Ucontrol 50 237VDC Uheating 1 0 1 2VDC SUPPLEMENT 10 Example of
44. n option is enabled the Calibration screen is displayed on the right panel of the PC monitor image Fig 3 Sup 19 It contains a three row table Search 47 and Calibration buttons and some additional controls and the Summary sweep plot above described in the Sweep option In the upper row Marker of the table 11 serial numbers of the calibration frequencies are inscribed Their genuine values in GHz as generated are shown in the row Fix Pressing the Search button will display their values as measured with the Analyzer using its preliminary calibration file in the row Found The calibration frequencies lying within the Analyzer frequency window are displayed with the green color and those lying beyond it are in the red These data may be seen on the Summary sweep plot in a graphic form If the Calibration Generator is not switched on or if less than two of the calibration frequencies are within the window only the Search button continues to be visible and enabled Decreasing the Noise level may result in detecting more calibration frequencies Another way to find out more calibration marks is to press repeatedly the Search button In some cases the averaged signal value may turn out to be higher than the individual one If two or more of the calibration frequencies got into the window the calibration can be realized by pressing the Calibration button after that the frequencies of both the rows o
45. n keyboard Press button Frequency Control to switch on LED on the button 14 To abort Control presses key Menu Feed the positive 2 8 VDC voltage into the plug Input 10 External Frequency Control The higher voltage corresponds to the higher output frequency H Save and load operation set up Generator automatically saves all settings from par A G just after one changes these Current set up is stored in memory and loaded after restart There are 10 user defined operation set ups stored in flash memory Each set up consists of the following settings Initial frequency Final frequency Fixed frequency Output power level oweep time Zoom width External of Internal Frequency control mode External of Internal Power control mode External Internal or OFF amplitude modulation mode GPIB address Save current settings in flash memory Only last settings are stored and then loaded in the device automatically If one would like to store some special set up he should to install desire settings as described in par A G Then one should enter to main menu Press the button Menu 12 if itis needed Press key 7 on Digital Keyboard 8 to activate command Save Pr from main menu Choose number of program from 0 to 9 pressing the corresponding key on Digital Keyboard 8 The current set up will be stored Load set up from flash memory If one would like to load set up saved in flash memory he shou
46. nal on the button Frequency Control 11 If LED not glows it means that the device is installed in Internal Frequency Control mode If LED glows one should run command Control of menu pressing key A on keyboard Press button Frequency Control to switch off LED on the button 11 To abort Control presses key Menu Set External Frequency control mode One should check LED External on the button Frequency Control 11 If LED glows it means that the device is installed in External Frequency mode If LED glows one should go to position Control of menu pressing key 4 on keyboard Press button Frequency Control to switch on LED on the button 11 To abort Control presses key Menu There are two modes of power control Internal and External Power Control modes Set Internal Power control mode One should check LED External on the button Power Control 14 If LED not glows it means that the device is installed in Internal Power Control mode If LED glows one should go to position Control of menu pressing key 4 on keyboard Press button Frequency Control to switch off LED on the button 14 To abort Control presses key Menu Set External Power control mode One should check LED External on the button Power Control 14 If LED glows it means that the device is installed in External Power Control mode If LED not glows one should go to position Control of menu pressing key 4 on keyboard Pre
47. nal positive voltage 0 10 VDC controls the output power of Generator e Set External Power Control mode Read Status String if bit 5 of 7 byte is set It means that the device is installed in External Power Control mode 4 activate local menu Control if 5 bit is clear A set External Power Control mode g abort local menu Control Read Status String Once more one should check 3 bit of 7 byte Frequency Control in Status String e Setthe fixed frequency as described in par 11 B e Feed the positive 0 10 VDC voltage into the plug Input 15 External Power Control The higher voltage corresponds to the higher output power G Set External Frequency Control mode through GPIB bus 16 In this mode an external positive voltage 2 8 VDC controls output frequency of Generator set External Frequency Control mode Read Status String If 7 bit of 7 byte is set it means that the device is installed in External Frequency Control mode 4 activate local menu Control if 7 bit is clear F set External Frequency Control mode q abort local menu Control Read Status String Once more one should check 7 bit of 7 byte Frequency Control in Status String Set output power as described in par 11 A Feed the positive 2 8 VDC voltage into the plug Input 10 External Frequency Control The higher voltage corresponds to the
48. ncy in any place of the whole band Then the 4096 conversions is made for this narrowed band Thus the maximum frequency resolution of the analyzer may be carried to the value as high as 60 kHz The entire device consists of Generator Heterodyne Receiver and microcomputer with Data Acquisition Card and software Functional scheme of entire device is presented on Supplement 18 Generator provides frequency sweeping LO for Heterodyne Receiver Output video signal of Heterodyne Receiver is proportional to the input RF power During the sweep the video signal is digitised by means of Data Acquisition Card installed into main microcomputer This scheme allows to obtain power spectrum of the input RF signal during each sweep of Generator 45 Main microcomputer controls the operation of Generator by means of GPIB bus Generator installs output power and frequency sweep accordingly instructions received from main microcomputer At the beginning of each sweep it sends synchronisation signals SYNC TTL to Heterodyne Receiver that is inverted in Receiver and mixed with output video signal Data Acquisition Card uses this negative pulse for the synchronisation with the beginning of the frequency sweep The signal Calibrator ON OFF switches on Harmonic Generator that built into Heterodyne Receiver The signal would be activated from microcomputer see User Manual for Generator It is needed for automatic calibration procedure 6 HOW TO TURN ON THE
49. nd you should go to step 3 If LED glows one should go to position Control of menu pressing key A on keyboard Press button Frequency Control to switch off LED on the button 14 To abort Control presses key Menu e Step 3 Set Amplitude Modulation OFF One should check LED OFF on the field Amplitude Modulation 13 If LED glows it means that the Amplitude Modulation switch off and you should go to step 4 If LED not glows press key 4 on Digital Keyboard 8 to activate local menu Control Press button Off in Amplitude Modulation group of buttons on Functional Keyboard 13 to switch off Internal Amplitude Modulation LED OFF should glow Press button Menu to abort local menu Control and return to main menu e Step 4 Seta Fixed Frequency Press key 3 on keyboard to activate the local menu Manual Wait few seconds if Generator asks that To enter the desired frequency one has three possibilities i Rotate Tuning Knob 6 and then press key Menu 12 Output operation frequency changes synchronously with value indicated on the display i Press buttons Step lt or gt 7 and then press key Menu 12 This way is useful if it is necessary to provide precision tuning One button realizing leads to the change of the frequency on the smallest available step Output operation frequency changes synchronously with value indicated on the display Enter frequency from Digital Keyboa
50. output of Generator Turn on the power The Power ON indicator 2 must glow and in approximately 40s READY indicator 3 must glow as well On LCD 5 a current time will be indicated and after about 4s the main menu will be activated All settings are stored automatically in flash memory of microcomputer Generator loads automatically last settings after switch on or restart Every time the 10 power level will be installed after the tuning on the Generator to avoid possible problems with high power output User should to install the higher power level if it is needed in the experiment Warm up time is approximately 30 min 9 PURSUANCE OF MEASUREMENTS A Frequency sweep mode In this mode Generator provides frequency sweep from the initial frequency to final one User would program both frequencies power and time of sweep The sweep is provided by saw tooth voltage During Sweep Time Control Unit provides linear 6 increasing of control voltage and then fast voltage decreasing during approximately 1 ms time Pay attention that the sweep is provided by linear increasing control voltage but frequency increases according the dependence of frequency versus control voltage that presented in Certification Card see Supplement 8 There are two modes of frequency sweep Internal and External Frequency Control modes Turn on the Generator as directed in part 8 Set Internal Frequency control mode One should check LED Exter
51. plug 29 for the triggering of external devices at the moment of the sweep beginning see Supplement 6 To stop sweep press key Menu D Internal Amplitude Modulation mode Square wave 100 amplitude modulation with frequency 1 kHz is provided in this mode Use Strobe Signal output plug 28 for the triggering of external devices Turn on the Generator as directed in par A Set operating frequency and power level as described in par A B Press key 4 on Digital Keyboard 8 to activate local menu Control Press button Internal in Amplitude Modulation group of buttons on Functional Keyboard 13 to switch on 1 kHz nternal Amplitude Modulation mode Press button Menu to abort local menu Control and return to main menu After that Generator will provide 1 kHz amplitude modulation E External Amplitude Modulation mode Square wave 100 amplitude modulation with frequency of an external triggering source is provided in this mode Turn on the Generator as directed in part 8 Set the desired frequency and power level as described in par A B Press key 4 on Digital Keyboard 8 to activate local menu Control Press button External in Amplitude Modulation group of buttons on Functional Keyboard 13 to switch on External Amplitude Modulation mode Feed the 5 V TTL positive pulses with a frequency in the range 1 100 kHz and duty ratio 2 square wave into the External Triggering Plug 16 Press
52. r Level the grid is defined in percents of voltage applied to Control Electrode of BWO tube In Supplement 7 dependencies of output power versus frequency for different voltage applied to control electrode in percents are presented Control Unit indicates Output Power also in percents of control voltage applied not in percents of real output power In the case of Sweep Time only one of the following values could be installed 0 01 0 02 0 04 0 08 0 1 0 2 0 4 0 8 1 2 4 8 10 20 80 100 Sec If one try to enter a value that isn t fitted to the grid exactly the fitting will be produced automatically Press Menu button 12 to abort local menu To start sweep press key 2 on Digital Keyboard 8 Generator indicates initial and final frequencies of sweep and starts sweep At the beginning of each sweep Generator produces TTL strobe pulses Use Strobe Signal output plug 29 for the triggering of external devices at the moment of the sweep beginning see Supplement 6 To stop sweep press key Menu B Fixed frequency mode At this mode the operation frequency is fixed Turn on the Generator as directed in part 8 Set Internal Frequency and Power control as described in par A Set the desired power level as described in par A Press key 3 on keyboard to activate the local menu Manual Wait few seconds if Generator asks that To enter the desired frequency one has three possibilities Rotate Tuning Knob
53. rd 8 A marker will appear on the display just after the realizing of one of the key 8 One can use buttons Step or gt 7 to change the marker position That allows edit the frequency on the display Press key Enter to finish editing and change the output operation frequency Press key Menu 12 If one will try to enter a wrong frequency out of operating frequency range max or min one available will be installed correspondingly 3l SUPPLEMENT 11 e Step 5 Set a desired Power Level Press key 1 on Digital Keyboard 8 to activate Set Up local menu There are four commands in the local menu Set Up Fr intl set initial frequency Fr set final frequency ime swp set sweep time Power Iv set power level Press key 4 to enter in local menu commands Power Iv Wait few seconds if Generator asks that To enter the desired value for example 10096 one has two possibilities i Rotate Tuning Knob 6 in clock direction and then press key Menu 12 Output power changes synchronously with value indicated on the display ii Enter Power Level from Digital Keyboard 8 Press keys 1 0 0 0 One can use buttons Step or gt 7 to change marker position That allows edit the value on the display Press key Enter to finish editing Output power changes after pressing key Enter Press key Menu 12 to go to main Menu BEN Setting
54. rs information about operating current and voltage for BWO tube For example Ih 2 3A laz 40mA Uh 1 14A Ug 230V is variable 3 40mA Ug is variable 3 230V 10 GPIB INTERFACE All commands and settings would be controlled through GPIB interface Connect the generator to GPIB bus plug 22 on the rear panel using special cable e Turn on the generator as directed in chap 9 par A e control of Generator one should send ASCII symbols corresponded to keys on keyboard or buttons on front panel according to the following table Keys or Buttons of Generator Symbol in GPIB port From O to 9 pec REN O0 to 9 RR eros DA Ext ee DOR Ext Amplitude Modulation Int Amplitude Modulation Off Amplitude Modulation Men B ANM Control lt A21l Application 100 Application 1000 R 12 The current the Generator settings may be read via GPIB bus in form of Status String Name Condition Finit Ffin Time ScreenCopy It consists of 6 information words separated with blanks The Status String dimension is variable and depends on the current status of the Generator The Name string occupies first six bytes from 1st to 6th For the Generator this string is fixed Name G4 143 The Condition hexadecimal word occupies bytes from 8th to 11th Correspondence between values of each Condition bit and the Generator settings are shown in the next tab
55. ss button Frequency Control to switch on LED on the button 14 To abort Control presses key Menu Setthe desired sweep time power level initial and final frequency Press key 1 on Digital Keyboard 8 to activate Set Up local menu There are four commands in the local menu Set Up 1 Fr intl set initial frequency 2 Fr fnl set final frequency Time swp set sweep time 4 Power lv set power level Press one of four keys from 1 to 4 to enter in local menu commands for example 1 Fr intl Wait few seconds if Generator asks that To enter the desired value one has three possibilities Rotate Tuning Knob 6 and then press key Menu 12 5 Press buttons Step or gt 7 and then press key Menu 12 This way is useful if it is necessary to provide precision tuning One button realising leads to the change of the value on the smallest available step Enter frequency from Digital Keyboard 8 One can use buttons Step lt or gt 7 to change marker position That allows edit the value on the display Press key Enter to finish editing Press key Menu 12 One can combine these three cases If one enter the value using Digital Keyboard Generator sets the nearest value from value grid that reflects the fact that output voltage of controlling 12 bits DAC s can t be installed with accuracy better then 1 4096 In the case of Powe
56. the mixing Intermediate Frequency IF signal is obtained on the detector Amplified signal is detected by the video detector and then conditioned by means of video amplifier 3 Principles of units operation schematic diagram of Receiver is shown on Supplement 14 Electrical scheme of IF Amplifier and Video amplifier is presented on Supplement 16 The Preamplifier is based on operating amplifier AD811 U1 Resistor R1 sets biasing current of the diode approximately 80 uA IF signal passes through capacitor C1 to preamplifier U1 amplifies signal with bandwidth from 4 to 16 5 MHz Filter R2 C1 define the low cut off frequency 4MHz The high cut off frequency 16 5 MHz is defined by frequency characteristics of U1 Different power suppliers are used for amplifier module together with detector biasing circuit R1 and other blocks of the scheme There is a possibility to change the gain of the amplifier x10 x100 and x1000 For this aim there is a voltage divider R6 R8 C4 C6 with relay commutation circuit K1 K2 One can change the gain manually using buttons Amplification 33 see Supplement 12 or remotely using 4 wires parallel interface TTL pulses 0 1 with a duration less then 20msec should be applied to Generator plug 38 according to the table presented below Signal Value 1 ON gain 10 6 21 Switch ON gain 100 7 1 gQySwitch ON gain 1000 1 Switch ON OFF AT of Harmonic Harmonic Gen
57. to action and disconnect the high voltage transformer In order to switch the high voltage source again it is necessary to turn off and then turn on the power switch The high incidence of activation of this circuit testifies that Generator is out of order The BWO control voltage overload protection circuit receives the signal proportional to the BWO decelerating system voltage This circuit is a part of the modulator circuit When BWO decelerating voltage falls down bellow 300 V the BWO control electrode voltage is switched off In particular this circuit comes into action when high voltage transformer is switched off The BWO heater overload protection circuit is a part of heat stabiliser circuit It provides the limitation of BWO heater current during the transition process at the turning on the Generator 7 OPERATION MANUAL ATTENTION Before turning on the Generator ensure that device is properly grounded using the corresponding contact L When using the Generator connected with other electrical devices the potentials of Generator and other devices must be equalised before the power is turned on Mentioned actions are not needed if you sure that the device is grounded in primary power plug It is prohibited to turn on the Generator unless a waveguide with a load is attached to the output waveguide of the Generator 8 HOW TO TURN ON THE GENERATOR Ground the Generator Ensure that fuses are present Attach a load to the
58. ut data on the IBM PC hard disc e basic frequency resolution of 15MHz and zoom mode with the resolution of 61 kHz 4 RELIABILITY 4 1 Main time to failure no less than 2000 h 4 2 909 life time no less than 2 years 5 PRINCIPLE OF OPERATION The Real Time Frequency Analyzer is typical swept frequency spectrum analyzer and uses the classic heterodyne based architecture Fig 1 Besides the double side band DSB heterodyne receiver the system incorporates the sweep generator with 120 to 180 GHz frequency band as local oscillator LO of the receiver The main part of the generator is back wave oscillator BWO Sweeping its output frequency is realized by means of saw tooth modulation of BWO accelerating potential Being supplied to the receiver the swept wave thus allows scanning input mm wave signal over the frequency during each sweep period so spectra repetition rate is equal to the sweep frequency At each time point of the each period output video signal of the receiver is proportional to a power of the input signal at given frequency within its spectrum This implies that both frequency and sensitivity calibration of the analyzer has to be carried out The frequency calibration of the receiver may be performed at any time when it is needed with aid of internal harmonic generator built in the receiver and providing 11 equidistant frequencies covering the band from 120 to 180 GHz As to the power calibration is concerned it is fulfil
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