Step Gain and 18.4 MHz Local Oscillator Adjustments | HP 8568B

10.Step Gain and 18.4 MHz Local Oscillator Adjustments

Reference

10. Step Gain and 18.4 MHz Local Oscillator Adjustments

IF-Display Section

A4A7 3 MHz Bandwidth Filter

A4A5 Step Gain

Related Performance Tests

Description

Resolution Bandwidth Selectivity Test

IF Gain Uncertainty Test

Center Frequency Readout Accuracy Test

First, the IF signal from the RF Section is measured with a power meter and adjusted for proper level. Next, the 10 dB gain steps are adjusted by connecting the CAL OUTPUT signal through two step attenuators to the RF INPUT and keying in the REFERENCE LEVEL necessary to activate each of the gain steps, while compensating for the increased gain with the step attenuators.

The 1 dB gain steps are checked in the same fashion as the 10 dB gain steps, and then the variable gain is adjusted. The 18.4 MHz oscillator frequency is adjusted to provide adequate adjustment range of front-panel FREQ ZERO control; and last, the + 1OV temperature compensation supply used by the A4A4 Bandwidth Filter and A4A8 Attenuator-Bandwidth Filter is checked and adjusted if necessary.

PMR METER

DIGITAL VOLTMETER

fi!&

1OdB S T E P 1 dB S T E P ATTENUATOR ATTENUATOR

Figure 3-46.

Step Gain and 18.4 MHz Local Oscillator Adjustments Setup

Adjustments 3-87

Image 201

HP 8568B manual Step Gain and 18.4 MHz Local Oscillator Adjustments Setup

Contents

Performance Tests and Adjustments Manual Page Certification Warranty Assistance General Safety Considerations Safety Symbols Section Troubleshooting Repair Manual Troubleshooting Repair ManualHP 85662A IF-DisplayIF-Display Section service information HP 8568B Spectrum Analyzer Documentation Outline 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 Frequency Counter Electronic = Universal Counter OscilloscopeProbe 10 1 Divider, compatible with oscilloscope HP 10432A Page DB Attenuator Power Splitter Directional BridgeTermination Low-Pass Filter 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 83640A Equipment1250-1250 5061-5458 10 Hz Sweep Time Accuracy Test 220 ms Sweep Time Accuracy Test Setup KHz Procedure Repeat steps 5 and 6 for each sweep time setting in Table 18 ms100 ms 90 ms Start-Up Time Measurement Sweep Time 20 s 200 s 32 s 48 s20 ms 50 ms 100 ms 500 ms 10 s 50 s 100 s 150 s Resolution Bandwidth Accuracy Test Specification &20%, 3 MHz10 dBm 90.0 kHz 110.0 kHz MHz 900 kHz 100 MHz00 kHz 11.00 kHz KHz 200 kHzPage DB Bandwidth Measurement MHz 20 MHz 100 Hz 15l 15 MHz 300 Hz 300 kHz 6OdB100 kHz MHz 30 kHz 500 kHz Procedure 1. Press Resolution Bandwidth Switching Uncertainty TestDBm Press LOG Enter dB/bIvj and key in 1 dB. Press Marker IlIl.00 Zto.50 Ito F0.50 DZo.50 F0.80 F2.00 Page +lO Fl dB Fl dB Related Adjustment Slope Compensation Adjustment Specification Signal InputFrequency Response Test ~tl.5 dB, 100 Hz to 1.5 GHz DB, 100 Hz to 500 MHz 100 Additional Equipment for OptionSynthesized Sweeper 120 s 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 Amplitude Related AdjustmentFidelity Test For instruments with Option 857, refer to Chapter +lO ~f1.5 dB JEGi 300 Hz Linear Fidelity 10. Key in analyzer settings as follows 10.87 23.10 17.72 501 HZ Average Noise Level Tkst80 dBm 1Hz 23. Average Noise Level Measurement Procedure 1. Press Instr Preset Residual Responses Test60 dBm Option Spurious Responses Test Frequency Synthesized3335A Ii 84&A Opt 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 Line-Related Sidebands Tests Specification Description Equipment Procedure10 dBm Wait for completion of sweep, then press Marker 20 MHz DBmWait for completion of the sweep, then press Marker Calibrator Amplitude Accuracy Test 32. Calibrator Amplitude Accuracy Test Setup Universal Related Adjustment NoneHP 5316A HP 8340A Approximately 1 Vp-p Triangular waveCAL position SYM CAL position F0.02 F0.05 10.0 fO.1 200 50.0 Iko.5 100 100 fl St LO Output Amplitude Test Frequency Reference Error Test Specification Aging RateRelated Adjustment Time Base Adjustment Page ‘lhble 2-19. Performance Tkst Record Tkst 1. Center Frequency Readout Accuracy Test Span Error 1Freq Span Spec ADUT- ASyn Min Max From ‘able Steps 7, 9, and 11. Wide Span Error‘I&t 2. Frequency Span Accuracy Test Test 2. Frequency Span Accuracy Test Sweep Time Accuracy, Sweep Times 220 ms Marker a Time Test 3. Sweep Time AccuracyMin Measured Max Min Measured ‘I&t 4. Resolution Bandwidth Accuracy Test 4. Resolution Bandwidth AccuracyMarker a Readout of 3 d 3 Bandwidth Min Measured Max Videobw 6 0 dB Test 5. Resolution Bandwidth SelectivityBandwidth 60dB BW t DB BW MHz 20 MHz 100 Hz 15l 1MHz 15MHz Bandwidth Switching Uncertainty Test 6. Resolution Bandwidth Switching Uncertainty TestDeviation Readout, dB Allowable Deviation Input Attenuator Switching Uncertainty Test 7. Input Attenuator Switching Uncertainty Test+lO Deviation Amplitude Ztl dB Kl dB Fl dB Kep Signal Input Test 8. Frequency Respons gTest 8. Frequency Response Test Test 9. RF Gain Uncertainty Test Nd LO Shift Min Measured Max+ 1.0 dB Test 10. if Gain Uncertainty Test F E R E N C E Level Step StepSteps 25 to 28. if Gain Uncertainty SteuI Min Measured Max YLkst 11. Log Scale Switching Uncertainty Tkst Xto.5HO.5 Test 12. Amplitude Fidelity Test Test 12. Amplitude Fidelity ‘I&tLinear Amplitude Fidelity Frequency Allowable Range Test 13. Average Noise Level Test Test 14. Residual Responses Test Test 14. Residual Responses TestMaximum Residual Response Frequency Range Measured Measured Max Max Amplitude Frequency Tkst 15. Spurious Responses Tkst DescriptionDBm -105 dBm -100 dBm 90 dBm Test 16. Residual FM Test Test 16. Residual FM TestResidual FM IMinIMeasuredIrax Min 1 M e a s u r e d M a x Tkst Line-Related Sidebands Test Test 18. Calibrator Amplitude Accuracy Test Test 18. Calibrator Amplitude Accuracy ‘I&tCAL Output Amplitude Min 10.3 dBm 70 dBm Test 19. Fast Sweep Time Accuracy Test ~20KO.02 Iko.05 10.0 fO.1 200 ps 50.0 f0.5 100 ps 100 fl 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 Adjustment Name ‘able 3-2. Adjustable Components Reference DesignatorAdjustment Number Adjustment Function SGlO Adjustable Components Reference Adjustment Designator Name Adjusts Linearity 12.5 to 18.6 GHz High end A6AlOR40 Adjusts Linearity 12.5 to 18.6 GHz Low end A6AlOR37Adjusts linearity 5.8 to 12.5 GHz A6AlOR41 Adjusts linearity 12.5 to 18.6 GHz Low end A6AlOR42 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 Delay Compensation A6A12C3 Delay Compensation A6A12C2 To 0.68 PF SetsDelay Compensation A6A 12C23 To 0.68 PF Sets Not loaded for HP 85660B A6A12Cll 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 Value n EP Fart Number ‘lhble Standard Value Replacement 0.125 Resistors0698-3447 0698-0082 Value ‘Ihble Standard Value Replacement 0.125 ResistorsBP Part Number Value !I ElP Fart Number Standard Value Replacement 0.5 Resistors Value fl BP Part Number 10.0 11.0 12.1Value 0 EIP Fart Number 383 422 464 110K 121K 133K 147K Ihble Standard Value Replacement 0.5 ResistorsEIP Fart Number Value a Procedure IF-Display Section Low-Voltage Power Supply AdjustmentsLow-Voltage Power Supply Adjustments Reference 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 High-Voltage Adjustment SN 3001A and Below High-Voltage Adjustment SN 3001A and BelowDescription High Voltage Adjustment Setup High-Voltage Adjustment Procedure Location of High Voltage Adjustments Level Remove the protective cover from the AlA High-VoltageLevel of approximately -4000 V dc. Be extremely careful Focus and Intensity Adjustments Press @%KiZi@Press Display Location of AlA Components CRT Cut-Off Voltage 10. Waveform at AlA3TP5 Discharge Procedure for High Voltage Following step, a large arc of high voltage should be drawnBe careful 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 Preliminary Display Adjustments SN 3001A and Below Preliminary Display Adjustments SN 3001A and BelowAdapters 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 Pulse Response of Control Gate Z Amplifier to Blank Input Press TlMEBASEIPress Itrig Level .00000 V c 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 Set the oscilloscope controls as follows Press Chan Delay 125.000 ns Press DisplayOffset Press Trig Source Level 25.0000 Press Time 27. Composite X Deflection Waveform Control Gate Z Amplifier to 29 OV,., Signal Description Procedure Final Display Adjustments SN 3001A and Below‘Ihble 3-5. Initial Adjustment Positions 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 Equipment Procedure Log Amplifier AdjustmentsRelated Performance Tests Offset Adjustment Check Linear Gain Adjustments VTV and Atten Adjustments Log Amplifier Adjustments Video Processor Adjustments Video Processor AdjustmentsRelated Performance Test Set step attenuator to 40 dB LOG Offset Adjust Adjustments 3-7 37 MHz Bandwidth Filter Adjustments Setup MHz Bandwidth Filter Adjustments Filter Center and Symmetry Adjustments MHz Bandwidth Filter AdjustmentsFrequency Zero Check Remove crystal filter bypass network near Cl4 SYM 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 + 10 V Temperature Compensation Supply Check A4A4 LC AdjustmentsLocation of A4A4 21.4 MHz LC Filter Adjustments A4A4 Xtal Adjustments Location of A4A4 21.4 MHz Crystal Filter AdjustmentsPress Marker loFF. Key in CREsJ 30 kHz A4A8 LC Adjustments Location of A4A8 21.4 MHz Crystal Filter Adjustments A4A8 Xtal AdjustmentsKey in t-1 100 kHz, C-1 200 kHz, and Marker Key in @TFTiTj 30 kHz, Frequency Span 100 kHz. Press 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 Step Gain and 18.4 MHz Local Oscillator AdjustmentsStep Gain and 18.4 MHz Local Oscillator Adjustments Setup 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 MHz Reference Adjustments Reference Adjustments13 MHz Type N m to BNC f Type N f to BNC f 57. Location of 20 MHz Reference Adjustments 1V / div Delay 40nsOffset Coupling 1Ol Press &K?@ Press CnTavj 58. Typical Signal at A16TP3 MHz Phase Lock Oscillator Adjustments MHz Phase Lock Oscillator AdjustmentsReference Description Type N m to BNC f 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 Second if Amplifier Adjustments Second if Amplifier and Third Converter Adjustment AdaptersBNC to SMB Snap-On Service Accessory 2 required Second if Amplifier and Third Converter Adjustment 66. Minimum Image Response at 258.4 MHz Third Converter Adjustment Pilot Second if Amplif’ier Adjustments Type N m to BNC f 2 required Type N f to BNC f 2 required1250-1745 1250-0780 1250-1474 1250-1749 Pilot Second if Amplifier Adjustments MHz Bandpass Filter Adjustments Waveforms Location of 269 MHz Bandpass Filter Adjustments Frequency Control Adjustments Frequency Control AdjustmentsHP 3456A 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 Second Converter Adjustments Second Converter AdjustmentsReference Related Performance S t 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 Dacs Accuracy Check Positive Supply Adjustment MHz Voltage-Tuned Oscillator AdjustmentsConnect DVM to AllTPl located on All cover Center-Frequency Checks VT0 Slope Compensation Adjustments Slope Compensation AdjustmentsSMA m m 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 Equipment ProcedureDigital Voltmeter DVM Place instrument upright as shown in -87 with top and A3 88. Location of Track and Hold Adjustments Track and Hold Adjustments Track and Hold Adjustments Reference Description Equipment Procedure Digital Storage Display AdjustmentsPreliminary Graticule Adjustments Digital Storage Display 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 DB Resolution Bandwidth Accuracy Test Description Equipment ProcedureRelated Adjustment Specification Page Impulse and Resolution Bandwidth Accuracy Test Page Impulse and Resolution Bandwidth Accuracy Test Page 10 kHz 100 kHz KHz 100 kHz MHz 30 kHz900 kHz MHz 90 kHz 110 kHz MHz 300 kHz 1FrequencyKHz 300 Hz 100 Hz 150 Hz 30 Hz Press DB Resolution Bandwidth Selectivity Test DB Bandwidth Measurement VlDEoj 60 dBMHz 20 MHz 100 Hz 11l 15 MHz 300 Hz 300 kHz 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