Second Converter Adjustments | HP 8568B guide

19. Second Converter Adjustments

9.Readjust A23A3 2ND MIXER A23A3Z4 for maximum power indication.

10.Disconnect the amplifier’s input from A23A3J3 and connect to A23A3J4.

11.Adjust A23A3 PILOT 2ND MIXER A23A3Z8 for maximum power meter indication. See Figure 3-73 for location of adjustment.

12.Disconnect power meter and connect frequency counter to amplifier’s output.

13.Key in [SHIFT) @) u to shift Second LO up and ISHIFT) a T to shift Second LO down.

14.Continue to shift Second LO up and down while adjusting A23A3 2ND LO SHIFT A23A3ZlO for a frequency difference of 5.0 MHz fO.l MHz. Ignore the absolute value of either frequency. Clockwise rotation of A23A3ZlO decreases the frequency difference.

15.Key in (SHIFT) a T (Second LO shifted down).

16.Adjust A23A3 2ND LO FREQ A23A3Z9 for frequency counter indication of 1748.6 MHz fO.l MHz.

17.Repeat steps 13 through 16 until specifications of steps 14 and 16 are achieved.

18.Disconnect frequency counter and connect power meter to the amplifier’s output.

19.Shift Second LO up and down, using m m u and (SHIFT) a T while adjusting A23A3 PILOT 2ND MIXER A23A3Z8 for equal power out in both states of Second LO.

20.Power difference between Second LO shifted up and shifted down should be less than 0.5 dB.

21.Disconnect amplifier’s input from A23A3J4 and connect to A23A3J3.

22.Shift Second LO up and down, using (SHIFTY a u and ISHIFT) @) T while adjusting A23A3 2ND MIXER A23A3Z4 for equal power out in both states of the Second LO.

23.Power differences between Second LO shifted up and shifted down should be less than 0.5 dB.

24.Disconnect power meter and connect frequency counter to amplifier’s output.

25.Key in [SHIFT) a T. Note frequency counter indication. If necessary, readjust A23A3 2ND LO FREQ A23A3Z9 for frequency counter indication of 1748.6 fO.l MHz.

26.Shift Second LO up and down, using ISHIFT) @) ’ and ISHIFT) a

T and note frequency difference between low and high state of Second LO. If necessary, readjust A23A3 2ND LO SHIFT A23A3ZlO for a frequency difference of 5.0 MHz fO.l. Repeat steps 27 and 28 until specifications contained in each step are achieved.

Adjustments 3-125

Image 239

HP 8568B manual Second Converter Adjustments

Contents

Performance Tests and Adjustments Manual Page Certification Warranty Assistance General Safety Considerations Safety Symbols HP 8568B Spectrum Analyzer Documentation Outline Troubleshooting Repair ManualSection Troubleshooting Repair Manual HP 85662A IF-DisplayIF-Display Section service information Contents Adjustments IF-Display Section Figure Index RF Section Figure Index Crystal Filter Bypass Network Configuration Figures Contents-5 Typical Bandpass Shift t 128 If Section, Bottom View Lhbles Introduction General Information Option 462 Instruments Option 857 Instruments HP 8340A HP 8640B HP 3335A HP 8116A HP 3312A HP 5061B Probe 10 1 Divider, compatible with oscilloscope HP 10432A Frequency Counter Electronic = Universal CounterOscilloscope Page Low-Pass Filter Power Splitter Directional BridgeDB Attenuator Termination Test Cable BNC m to SMB Snap-On f SMA m to SMA m HP5061-5458 08505-60109 Figure l-l. Service Accessories, HP Part Number Performance Tksts Able 2-1. Performance Test Cross-Reference Center Frequency Readout Accuracy ‘I&t Specification uncorrected Center Frequency Readout Error Measurement MHZ\I Frequency Span Accuracy lkst Specification 5061-5458 Equipment83640A 1250-1250 10 Hz Sweep Time Accuracy Test 220 ms Sweep Time Accuracy Test Setup KHz Procedure 100 ms 90 ms Repeat steps 5 and 6 for each sweep time setting in Table18 ms 20 ms 50 ms 100 ms 500 ms 10 s 50 s 100 s 150 s Start-Up Time Measurement Sweep Time20 s 200 s 32 s 48 s 10 dBm Resolution Bandwidth Accuracy TestSpecification &20%, 3 MHz 200 kHz MHz 900 kHz 100 MHz90.0 kHz 110.0 kHz 00 kHz 11.00 kHz KHzPage DB Bandwidth Measurement 30 kHz 500 kHz 6OdBMHz 20 MHz 100 Hz 15l 15 MHz 300 Hz 300 kHz 100 kHz MHz Press LOG Enter dB/bIvj and key in 1 dB. Press Marker Resolution Bandwidth Switching Uncertainty TestProcedure 1. Press DBm IlIl.00 Zto.50 Ito F0.50 DZo.50 F0.80 F2.00 Page +lO Fl dB Fl dB ~tl.5 dB, 100 Hz to 1.5 GHz DB, 100 Hz to 500 MHz Specification Signal InputRelated Adjustment Slope Compensation Adjustment Frequency Response Test 120 s Additional Equipment for Option100 Synthesized Sweeper 12. Frequency Response Measurement 20 MHz to 1.5 GHz 5GHz Option 001 + 4 dBm Page KHz to 20 MHz MaximumdBm MinimumdBm 100 kHz Set function generator controls as follows Spec ~3 dB Overall Maximum DBm Minimum Deviation Hz to 1.5 GHz from steps 15, 16, 25, 42, orPage 16. RF Gain Uncertainty Measurement DBm to -55.9 dBm DBm to -129.9 dBm If Gain Uncertainty Test LOG Procedure 1. Press Instr pfwm 18. if Gain Uncertainty Measurement 19. if Gain Uncertainty Measurement 2 dB Largest Positive Deviation Negative Amplitude Page F0.5 Log Scale Switching Uncertainty Test For instruments with Option 857, refer to Chapter Related AdjustmentAmplitude Fidelity Test +lO ~f1.5 dB JEGi 300 Hz Linear Fidelity 10. Key in analyzer settings as follows 10.87 23.10 17.72 1Hz Average Noise Level Tkst501 HZ 80 dBm 23. Average Noise Level Measurement 60 dBm Procedure 1. Press Instr PresetResidual Responses Test Option Spurious Responses Test Ii 84&A Opt SynthesizedFrequency 3335A Performance Tests 2 Intermodulation Distortion 26. Intermodulation Distortion Test Setup Fl fz 211 2f2 Center Frequency 1 MHZ, Marker Peak Search to position Spurious Responses Test Residual FM Test Hr RF -I... L 1u 29. Slope Detected Residual FM Performance Tests 2 Wait for completion of sweep, then press Marker Specification Description Equipment ProcedureLine-Related Sidebands Tests 10 dBm Wait for completion of the sweep, then press Marker 20 MHzDBm Calibrator Amplitude Accuracy Test 32. Calibrator Amplitude Accuracy Test Setup HP 8340A Related Adjustment NoneUniversal HP 5316A SYM CAL position Triangular waveApproximately 1 Vp-p CAL position F0.02 F0.05 10.0 fO.1 200 50.0 Iko.5 100 100 fl St LO Output Amplitude Test Related Adjustment Time Base Adjustment Frequency Reference Error TestSpecification Aging Rate Page ‘lhble 2-19. Performance Tkst Record Tkst 1. Center Frequency Readout Accuracy Test Test 2. Frequency Span Accuracy Test Steps 7, 9, and 11. Wide Span ErrorSpan Error 1Freq Span Spec ADUT- ASyn Min Max From ‘able ‘I&t 2. Frequency Span Accuracy Test Min Measured Test 3. Sweep Time AccuracySweep Time Accuracy, Sweep Times 220 ms Marker a Time Min Measured Max Marker a Readout of 3 d 3 Bandwidth Min Measured Max ‘I&t 4. Resolution Bandwidth AccuracyTest 4. Resolution Bandwidth Accuracy MHz 20 MHz 100 Hz 15l 1MHz 15MHz Test 5. Resolution Bandwidth SelectivityVideobw 6 0 dB Bandwidth 60dB BW t DB BW Readout, dB Allowable Deviation Test 6. Resolution Bandwidth Switching Uncertainty TestBandwidth Switching Uncertainty Deviation Deviation Amplitude Ztl dB Kl dB Fl dB Test 7. Input Attenuator Switching Uncertainty TestInput Attenuator Switching Uncertainty +lO Test 8. Frequency Response Test Kep Signal InputTest 8. Frequency Respons g + 1.0 dB Test 9. RF Gain Uncertainty TestNd LO Shift Min Measured Max Test 10. if Gain Uncertainty Test F E R E N C E Level Steps 25 to 28. if Gain Uncertainty SteuI Min Measured Max StepStep HO.5 YLkst 11. Log Scale Switching Uncertainty TkstXto.5 Allowable Range Test 12. Amplitude Fidelity ‘I&tTest 12. Amplitude Fidelity Test Linear Amplitude Fidelity Frequency Test 13. Average Noise Level Test Measured Measured Max Max Amplitude Frequency Test 14. Residual Responses TestTest 14. Residual Responses Test Maximum Residual Response Frequency Range DBm -105 dBm -100 dBm 90 dBm Tkst 15. Spurious Responses TkstDescription Residual FM IMinIMeasuredIrax Test 16. Residual FM TestTest 16. Residual FM Test Min 1 M e a s u r e d M a x Tkst Line-Related Sidebands Test 10.3 dBm 70 dBm Test 18. Calibrator Amplitude Accuracy ‘I&tTest 18. Calibrator Amplitude Accuracy Test CAL Output Amplitude Min KO.02 Iko.05 10.0 fO.1 200 ps 50.0 f0.5 100 ps 100 fl Test 19. FastSweep Time Accuracy Test ~20 Test 20 st LO Output Amplitude Test St LO Output Level Test 20 st LO Output Amplitude Test DescriDtion Min 1 Measured Max Test 21. Frequency Reference Error Slope Compensation Adjustment Video Processor Adjustments MHz Bandwidth Filter Adjustments Safety Considerations Equipment Required Adjustment Tools Factory-Selected Components Related Adjustments Location of lkst Points and Adjustments ‘Ihble 3-2. Adjustable Components Adjustment Adjustment Function Number SGlO ‘able 3-2. Adjustable Components Reference DesignatorAdjustment Name Adjustment Number Adjustment Function Adjustable Components Reference Adjustment Designator Name Adjusts linearity 12.5 to 18.6 GHz Low end A6AlOR42 Adjusts Linearity 12.5 to 18.6 GHz Low end A6AlOR37Adjusts Linearity 12.5 to 18.6 GHz High end A6AlOR40 Adjusts linearity 5.8 to 12.5 GHz A6AlOR41 Adjustment Name Number ‘Ihble 3-2. Adjustable Components Reference Designator If Serial Prefix 3001A and Below If Serial Prefix 2637A and Below Function of Component ’hble 3-3. Factory-Selected Components Range of Values Function of Component Procedure Or PF To 17.8 K To 13.3 K 10 38.3 to 100 to 383 to To 2.61 K Adjustment Range of Values Procedure 0 or PF Below, see the back This table for exceptions to A4A9 ?or Serial Prefix 2813A To 2816A, and Serial Prefix 2810A Not loaded for HP 85660B A6A12Cll To 0.68 PF Sets Delay Compensation A6A12C2 To 0.68 PF SetsDelay Compensation A6A12C3 Delay Compensation A6A 12C23 To 0.68 PF Sets Serial Prefix 2810A and Below Serial Prefix 2813A to 2816A Option Value pF 1BP Fart Number CD Value pF ZP Fart Number s ‘lkble 3-4. Standard Value Replacement Capacitors 0698-0082 ‘lhble Standard Value Replacement 0.125 ResistorsValue n EP Fart Number 0698-3447 Value !I ElP Fart Number ‘Ihble Standard Value Replacement 0.125 ResistorsValue BP Part Number Value 0 EIP Fart Number 383 422 464 Standard Value Replacement 0.5 ResistorsValue fl BP Part Number 10.0 11.0 12.1 Value a Ihble Standard Value Replacement 0.5 Resistors110K 121K 133K 147K EIP Fart Number Reference Low-Voltage Power Supply AdjustmentsProcedure IF-Display Section Low-Voltage Power Supply Adjustments IF-Display Section Low-Voltage Adjustments SN 3004A Above IF-Display Section Low-Voltage Adjustments SN 3001A Below RF Section Location of RF Section Low-Voltage Adjustments Low-Voltage Power Supply Adjustments Description High-Voltage Adjustment SN 3001A and BelowHigh-Voltage Adjustment SN 3001A and Below High Voltage Adjustment Setup High-Voltage Adjustment Procedure Location of High Voltage Adjustments Level of approximately -4000 V dc. Be extremely careful LevelRemove the protective cover from the AlA High-Voltage Press Display Focus and Intensity AdjustmentsPress @%KiZi@ Location of AlA Components CRT Cut-Off Voltage 10. Waveform at AlA3TP5 Be careful Discharge Procedure for High VoltageFollowing step, a large arc of high voltage should be drawn 1. Discharging the CRT Post-Accelerator Cable High-Voltage Adjustment SN 3004A and Above High-Voltage Adjustment SN 3004A and Above 12. High Voltage Adjustment Setup Level Approximately -2400 V dc can present even when the ac line 14. Location of AlA Label and Test Point Remove the ac line cord from both instrument sections 15. Discharging the CRT Post-Accelerator Cable Adapters Preliminary Display Adjustments SN 3001A and BelowPreliminary Display Adjustments SN 3001A and Below 16. Preliminary Display Adjustments Setup Procedure Y Deflection Amplifier Pulse Response Adjustments 17. Location of AlA2, AlA4, AlA5, and A3A2 ~000uu000000u00urPage 20. Composite X Deflection Waveform Rise and Fall Times and Overshoot Adjustment Waveform Press Itrig Level .00000 V c Pulse Response of Control Gate Z Amplifier to Blank InputPress TlMEBASEI Set the oscilloscope controls as follows Press @iK 22 OV,, Signal Preliminary Display Adjustments SN 3004A and Above 23. Preliminary Display Adjustments Setup Preliminary Display Adjustments SN 3004A and Above 24. Location of AlA and A3A2 Press Trig Source Level 25.0000 Press Time Delay 125.000 ns Press DisplaySet the oscilloscope controls as follows Press Chan Offset 27. Composite X Deflection Waveform Control Gate Z Amplifier to 29 OV,., Signal ‘Ihble 3-5. Initial Adjustment Positions Description ProcedureFinal Display Adjustments SN 3001A and Below Location of Final Display Adjustments on AlA2, AlA4, and AlA 31. Final Display Adjustments Setup Final Display Adjustments SN 3004A and Above RI20R220R512R513 R319 R426 R437 Adjustments 3 Final Display Adjustments SN 3004A and Above Related Performance Tests Equipment ProcedureLog Amplifier Adjustments Offset Adjustment Check Linear Gain Adjustments VTV and Atten Adjustments Log Amplifier Adjustments Related Performance Test Video Processor AdjustmentsVideo Processor Adjustments Set step attenuator to 40 dB LOG Offset Adjust Adjustments 3-7 37 MHz Bandwidth Filter Adjustments Setup MHz Bandwidth Filter Adjustments Remove crystal filter bypass network near Cl4 SYM MHz Bandwidth Filter AdjustmentsFilter Center and Symmetry Adjustments Frequency Zero Check Key in Csweep Time 20 ms, Frequency Span 0 Hz, CREs 10 Hz Filter Peak Adjust 39. Location of 3 MHz Peak Adjustments MHz Bandwidth Filter Adjustments Hz Amplitude Adjustments 40 .4 MHz Bandwidth Filter Adjustments Setup Location of A4A4 21.4 MHz LC Filter Adjustments + 10 V Temperature Compensation Supply CheckA4A4 LC Adjustments Press Marker loFF. Key in CREsJ 30 kHz A4A4 Xtal AdjustmentsLocation of A4A4 21.4 MHz Crystal Filter Adjustments A4A8 LC Adjustments Key in @TFTiTj 30 kHz, Frequency Span 100 kHz. Press A4A8 Xtal AdjustmentsLocation of A4A8 21.4 MHz Crystal Filter Adjustments Key in t-1 100 kHz, C-1 200 kHz, and Marker LC Dip Adjustments AlOdB and A20dB Adjustments DB Bandwidth Adjustments 45. Location of 3 dB Bandwidth Adjustments DB Bandwidth Adjustments DB Bandwidth Adjustments Step Gain and 18.4 MHz Local Oscillator Adjustments Setup Step Gain and 18.4 MHz Local Oscillator AdjustmentsStep Gain and 18.4 MHz Local Oscillator Adjustments 47. Location of if Gain Adjustment If Gain Adjustment 48. Location of 10 dB Gain Step Adjustments DB Gain Step Adjustment MHz Local Oscillator Adjustment Key in Frequency Span 1kHz, REs 100 Hz, + 1OV Temperature Compensation Supply Adjustment Down/Up Converter Adjustments Optional Down/Up Converter Adjustments Down Converter Gain Adjustment Cables 52. Time Base Adjustment Setup Procedure Note Set the Frequency Counter controls as follows 53. Location of A27Al Adjustment Time Base Adjustment SN 2848A to 3217A05567 Time Base Adjustment SN 2848A to 3217A05567 X10 Math SELECT/ENTER Cm 10 I-1 6 SELECT/E~&ER 55. Location of A27A2 Adjustment Type N m to BNC f Type N f to BNC f Reference AdjustmentsMHz Reference Adjustments 13 MHz 57. Location of 20 MHz Reference Adjustments 1Ol Delay 40ns1V / div Offset Coupling Press &K?@ Press CnTavj 58. Typical Signal at A16TP3 Type N m to BNC f MHz Phase Lock Oscillator AdjustmentsMHz Phase Lock Oscillator Adjustments Reference Description Location of 249 MHz Phase Lock Oscillator Adjustments Single Page Disconnect test equipment from instrument MHz Phase Lock Oscillator Adjustment 63. Second if Amplifier Adjustments Setup Second if Amplifier and Third Converter Adjustment BNC to SMB Snap-On Service Accessory 2 required Second if Amplifier AdjustmentsSecond if Amplifier and Third Converter Adjustment Adapters Second if Amplifier and Third Converter Adjustment 66. Minimum Image Response at 258.4 MHz Third Converter Adjustment 1250-1745 1250-0780 1250-1474 1250-1749 Pilot Second if Amplif’ier AdjustmentsType N m to BNC f 2 required Type N f to BNC f 2 required Pilot Second if Amplifier Adjustments MHz Bandpass Filter Adjustments Waveforms Location of 269 MHz Bandpass Filter Adjustments HP 3456A Frequency Control AdjustmentsFrequency Control Adjustments Start-Up Time Slow Sweep Adjustment YTO and VT0 DAC Adjustments Full Sweep Adjustment Key in ml CF Step Size J 1023 Hz Start and Stop Adjustments S t Second Converter AdjustmentsSecond Converter Adjustments Reference Related Performance Set HP 8568B Spectrum Analyzer Line to on and press Second LO Frequency and Shift Adjustments Second Converter Adjustments Second Converter Bandpass Filter Adjustments 74. Typical Pilot 2ND if Bandpass Shift t 1i i i i ii i Second Converter Final Adjustments 78 MHz Voltage-Tuned Oscillator Adjustments Setup Voltage-Tuned Oscillator Adjustments Connect DVM to AllTPl located on All cover Dacs Accuracy Check Positive Supply AdjustmentMHz Voltage-Tuned Oscillator Adjustments Center-Frequency Checks VT0 SMA m m Slope Compensation AdjustmentsSlope Compensation Adjustments Leveling EXT Input 81. Location of A22R66 Tiiit Adjustment 83. Location of Comb Generator Adjustments Comb Generator Adjustments 84. Comb Teeth Display Comb Generator Adjustments Comb Generator Adjustments 85. Analog-To-Digital Converter Adjustments Setup Analog-To-Digital Converter Adjustments Location of Analog-To-Digital Converter Adjustments Press Qnstr Preset Place instrument upright as shown in -87 with top and A3 ProcedureEquipment Digital Voltmeter DVM 88. Location of Track and Hold Adjustments Track and Hold Adjustments Track and Hold Adjustments Digital Storage Display Adjustments Digital Storage Display AdjustmentsReference Description Equipment Procedure Preliminary Graticule Adjustments 90. Location of Digital Storage Display Adjustments 91. Sample and Hold Balance Adjustment Waveforms Sample and Hold Balance Adjustments Y Offset and 25. Gain Adjustments Final Graticule Adjustments Y Expand Adjustments Low-Noise DC SUPPlY Crystal Filter Bypass Network Configuration Crystal Filter Bypass Network Configuration Impulse Bandwidths Option Related Adjustment Specification DB Resolution Bandwidth Accuracy TestDescription Equipment Procedure Page Impulse and Resolution Bandwidth Accuracy Test Page Impulse and Resolution Bandwidth Accuracy Test Page 90 kHz 110 kHz 100 kHz MHz 30 kHz10 kHz 100 kHz KHz 900 kHz MHz 100 Hz 150 Hz 30 Hz 1FrequencyMHz 300 kHz KHz 300 Hz Press DB Resolution Bandwidth Selectivity Test DB Bandwidth Measurement MHz 20 MHz 100 Hz 11l 15 MHz 300 Hz 300 kHz VlDEoj60 dB Page Impulse and Resolution Bandwidth Selectivity Test Selectivity Frequency ‘EG Bandwidth DB BW Ratio Span Press LOG Enter dB/otv and key in 1 dB. Press Marker Procedure 1. Press ~NSTR Preset MHz 500 kHz 50 kHz 10 kHz KHz KHz 200 Hz 100 Hz LdB’ t-H+ ‘RES Steps 1 through 38. Impulse Bandwidth Accuracy Option MHz 20 MHz 100 Hz 11l 15 MHz 300 Hz 111 300 kHz MHz 100 Hz 11l 300 Hz 300 kHz Ref. xt 1.0 It Zt 0.5 xt F 0.5 f 0.5 f 0.5 f 0.8 f Test DB Resolution Bandwidth Adjustments Location of Bandwidth Adjustments DB Resolution Bandwidth Adjustments Impulse Bandwidth Adjustments C O N T R O L Key in @E’GZT 3 kHz, Frequency Span 5 kHz, Peak SEARCH, Introduction Related Adjustment Log Amplifier Adjustments Specification Log + 10 dBm Option 857 Amplitude Fidelity Test Frequency Sk1.0 dB %1.5 dB Marker a Performance Test Record DB sf1.5 dB Test 12. Option Amplitude Fidelity Test Min Max 6-5 6-6 6-5 RF Section Figure Index Major Assembly and Component locations RF Section, Top View RF Section, Front View RF Section, Bottom View \.\ \ I ‘i If Section, Top View SN 3004A and Above If Section, Front View W2g