HP-1415A-Manual 电路图.pdf

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1、w TIME DOMAIN REFLECTOM ETER 1415A RadioFans.CN 收音机爱 好者资料库 CERTIFICATION The Hewlett-Packard Company certifies that this instrument toas thoroughly tested and inspected and found to meet its published specifications when it was shipped from the factory. The Hewlett- Packard Company further certifies

2、 that its calibration measure- ments are traceable to the U.S. National Bureau of Standards to the extent allowed by the Bureaus calibration facility. WARRANTY AND ASSISTANCE All Hewlett-Packard products are warranted against defects in materials and workmanship. This warranty applies for one year f

3、rom the date of delivery, or, in the case of certain major compo- nents listed in the operating manual, for the specified period. We will repair or replace products which prove to be defective during the warranty period provided they are returned to Hewlett- Packard. No other warranty is expressed o

4、r implied. We are not liable for consequential damages. Service contracts or customer assistance agreements are available for Hewlett-Packard products that require maintenance and re- pair on-site. For any assistance, contact your nearest Hewlett-Packard Sales and Service Office. Addresses are provi

5、ded at the back of this manual. . . * . RadioFans.CN 收音机爱 好者资料库 1 01 944-5 PRINTED: JUN 1968 OPERATING AND SERVICE MANUAL MODEL 1415A TIME DOMAIN REFLECTOMETER SERIALS PREFIXED: 622,623- See Section I For Instruments With Other Serial Prefixes See Section I and Appendix I For Instruments With Option

6、s WWW. H PA RCHIVE.COM For Free Distribution Only C o p y r i g h t H E W L E T T - P A C K A R D C O M P A N Y 1964 1501 P A G E MILL R O A D , P A L O A L 7 0 , C A L I F O R N I A , U . S . A . RadioFans.CN 收音机爱 好者资料库 Table of Contents Model 1415A TABLE OF CONTENTS Sect I I1 I11 Iv v ion Page 1-1

7、. Description 0 - - - - - - - - - 1-1 1-6. Manual Identification . - - * - * - 1-1 1-8. Scope of Manual . - - * - - * 1-1 GENERAL INFORMATION * . * * * * . 1-1 1-4. Options . . . . . . . . . . . . . . 1-1 INSTALLATION * * * * . * . * * * 2-1 2-1. Initial Inspection - - - - - 0 - 2-1 2-4. Damage Clai

8、m and Repackaging - 2-1 2-7. Preparation for Use . - + - - - 2-2 OPERATION . . . . . . . . . . . . . . . . 3-1 3-1. Introduction . . - . . . - . - 3-1 3-3. Controls and Connectors - . 0 - - 3-1 3-13. Applications - - - - - i 3-1 3-10. Operation . . . . . . . . . . . . . . 3-1 PRINCIPLES OF OPERATION

9、 * - - 0 * . 4-1 4-1. Introduction . . 0 - - 0 . . - - - - 4-1 4-3. Circuit Details - - . - - - - - 4-1 4-4. Step Generator . - - . - 4-1 4-9. Slow Ramp Generator - - . - - 4-3 4-13. Dot Generator - - - - - - - - 4-3 4-17. Fast Ramp Generator - . - - 0 4-3 4-19. Ramp Comparator - - - 4-5 4-23. Verti

10、cal Amplifier . - - - - - 4-5 4-25. Horizontal Amplifier - - 4-5 4-27. Power Supply. - . - - - - - - . 4-5 4-21. Sampler . . . . . . . . . . . . . . 4-5 MAINTENANCE . . . . . . . . . . . . . . 5-1 5-1. Introduction - - - . - - - . . - 5-1 5-3. Performance Check - - - . - - 5-1 5-5. Test Equipment -

11、- - - . * 5-1 5-7. Procedure - - - * * - - - - * 5-1 Section Page 5-9. Front Panel Preliminary Settings * 5-1 5-10. Ref1 Coefficient Attenuator * - - * 5-1 5-11. Distance/Time Scale. * - * * - * 5-1 5- 12. Rise Time, Jitter, and Internal Reflections - - - - - * - - * * * - 5-2 5-13. Overshoot and Ri

12、nging - - * - - * 5-2 5- 14. . . . . . . . . . . . . . . . 5-2 5-15. Noise and Internal Pickup * - * 5-2 5-16. Output Impedance * - * - - - * - 5-2 5-17. Dynamic Range - * - * * * - 5-18. Adjustments - - - * * * * * * 5-3 5-22. Procedure - - - - - - * * * * 5-3 p * s.5-2 5-24. Power Supply Adjustmen

13、t - * - * - 5-3 5-25. Step Stability Adjustment - - - * 5-3 5-26. Step Zero Level Adjustment - - - 5-4 5-27. SamplerDiode Bias Adjustment * - 5-4 5-28. Step Cal Adjustment * - - - - - 5-4 5-29. Dist/Time Cal Adjustment . - * 5-4 5-30. Dist/Time Cal Adjustment * * * * 5-4 5-31. Time Scale Cal and 20-

14、NSEC Time 5-32. Time Scale Cal Adjustment - - 5-4 5-36. Dot Delay Adjustment . . . . . . 5-4 5-37. Zero Set Adjustments - - - * 5-5 5-38. Pulse Shape Adjustment . . . . . . 5-5 5-39. Troubleshooting 0 0 - 0 - - . . 5-5 5-42. General Troubleshooting. . . . . . 5-5 5-50. Specific Troubleshooting. - -

15、- - 5-6 5-52. Component Location . . . . . . . . 5-6 5-54. Servicing Etched Circuit. - - - - 0 5-4 6-1. Introduction . . - - . - - - -6-1 6-3. OrderingInformation - * - * -6-1 APPENDMI. OPTIONS - - - * - IA-1,hA-Z Scale Cal Adjustments 0 * - * 5-4 VI REPLACEABLE PARTS . * - * * * a 6-1 APPENDIX II.

16、MANUAL CHANGES * * * - * * IIA-1 ii 01944-3 Model 1415A LIST OF ILLUSTRATIONS List of Illustrations and Tables Number Title Page 1-1. 3-1. 3-2. 3-3. 3-4. 3-5. 3-6. 4- 1. 4-2. 4-3. 4-4. 5-1. 5-2. 5-3. 5-4. 5-5. 5-6. 5-7. 5-8. 5-9. Model 1415A Time Domain Reflectometer. 110 Model 1415A Controls and Co

17、nnectors . - 3-2 Vertical Calibration . 3-4 Horizontal Calibration - . . - . 3-5 Reflection Measurements . 3-6 TransmissionMeasurements . . - . 3-7 Initial Operation . 3-3 Step Generator, and Fast Ramp and Comparator Model 1415A Block Diagram - 4-1 Horizontal Amplifier, and Slow Ramp and Dot Compara

18、tor BlockDiagram . - . - 4-2 Sampler and Vertical Amplifier Block BlockDiagram . 4-0 Diagram . 4-4 Location of Adjustments . 5-3 Model 1415A Component Location, TopView -5-9 Model 1415A Component Location, Bottom Component Locations on A2, Pulse Generator Waveforms at Test Points in Step Generator V

19、iew . 5-9 Board . 5-10 Circuit . 5-10 Step Generator Schematic Diagram . 5-11 Component Locations on A10, Distance/Time Magnifier Switch . 5-12 Component Locations on A13, Sweep Switch 5-12 Component Locations on Al, Time Base Board. . -5-12 5-10. Waveforms at Test Points in Slow Ramp and 5-11. Slow

20、 Ramp and Dot Comparator Schematic 5- 12. Component Locations on A9, Distance/Time CM Line/CM Display Switch . . - Dot Comparator Circuits - - - . -5-12 Diagram . 5-13 - 5-14 Number Title Page Comparator Circuits * * * - * 5-14 5-13. Waveforms at Test Points in Fast Ramp and 5-14. Fast Ramp and Comp

21、arator Schematic 5-15. Component Locations on Sampler Block 5-16. Component Locations on A3, Sampler 5-17. Waveforms at Test Points in Sampler 5-18. Sampler Schematic Diagram * * * * 5-17 5-19. Component Locations on A5, Amplifier 5-20. Component Locations on A7, Trimmer 5-2 1. Component Locations o

22、n A8, Reflection Coefficient Switch- * * - * 5-18 5-22. Horizontal Amplifier Schematic Diagram * 5-18 5-23. Vertical Amplifier Schematic Diagram * 5-19 5-24. Power fhpply Schematic Diagram * - 5-20 5-25. Component Locations on A6, Power fhpply 5-26. Interconnection Plugs Schematic IA-1. Components L

23、ocations onA9, IA-2. Option 14Distance/Time Switch Diagram . 5-15 Assembly . 5-16 Board. . 5-16 Circuit . 5-16 Board. . 5-18 Board. . 5-18 Board. . 5-20 Diagram. . 5-20 Option 14 IA-l/IA-2 . . . . . . . . . . . Schematic. . . . . . . . . . . IA-3/IA-4 IIA-2. Time Base Board A1 - - - 0 * IIA- S/IIA-

24、io IIA-1. Controls and Connectors * - - - . IIA-7/IIA-8 IIA-3. Partial Schematic, Slow Ramp and Dot Comparator * - - - IIA-9 /IIA-lO IIA-4. Amplifier Board A5- 0 * - - IIA-lI/IIA-12 IIA-5. Trimmer Board A7 * * - - * - IIA-ll/IIA-12 IIA-7. QlOl Emitter Circuit- * - - - IIA-ll/IIA-12 IIA-8. Pulse Gene

25、rator Board A2 * * IIA-ll/IIA-12 IIA-9. Pulse Shape Adjust Circuit * * IIA-ll/IIA-12 IIA-6. Power Supply Board A6 - - IIA- 1 1/IIA- 12 LIST OF TABLES Number Title Page Number Title J?age 1-1. Specifications - - - . - . . . 1-0 5-6. Schematic Diagram Notes - . - - 5-8 6-1. ReferenceDesignationIndex *

26、 0 * - - * 6-2 5-1. 6-2. Replaceable Parts * - * * * - 6-15 5-2. Vertical Magnifier Check . * - 5-1 6-3. Code List of Manufacturers * * * - 6-20 5-3. Distance/Time Scale Check - - . - - - 5-2 5-4. SDecific Troubleshooting 5-7 IA-1. Option 14 Replaceable Parts IA-0 Equipment Required for Tests and Ad

27、justments . 5-0 . . 5-5. Conditions for Waveform and DC Voltage IIA- 1. Reference Designatioc Index and Replaceable Measurements . 5-8 Parts . uA-5/nA-6 019 44- 3 iii Section I Figure 1- 1 and Table 1- 1 Model 1415A Figure 1- 1. Model 1415A Time Domain Reflectometer Table 1-1. Specifications SYSTEM

28、(in reflectometer configuration) RISE TIME: Less than 150 psec. OVERSHOOT: 5% or less overshoot and ringing (down to 1/2% in 2 nsec). INTERNAL REFLECTIONS: Less than 10% (does not limit resolution). REFLECTOMETER SENSITIVITY: Reflection coefficients as small as 0.001 can be observed. REPETITXON RATE

29、: 150 kc nominal. SIGNAL C H A N N E L RISE TIME: Approximately 110 psec. REFLECTION COEFFICIENT: 0.5/cm to 0.005/ INPUT: 50 ohms, feed-through type. NOISE AND INTERNAL PICKUP, PEAK 0.1% of step (terminated in 50 ohms). DYNAMIC RANGE: +O. 5 volt. EXTERNAL SIGNAL LEVEL: Up to 1 v peak may ATTENUATOR

30、ACCURACY: i3%. cm in 1,2,5 sequence. be safely applied to the SIGNAL OUT connector. STEP GENERATOR AMPLITUDE: Approximately 0.25 v into 50 ohms RISE TIME: Approximately 50 psec. OUTPUT IMPEDANCE: 50 ohms i1 ohm. (0.5 v into open circuit). DROOP: Less than 1%. D ISTAN CE/TIME SCALE DISTANCE SCALE ACC

31、URACY (cm of Line/cm of POLYETHYLENE LINE ( E =2.25): 200 cm/cm AIR LINE (E=l): 300 cm/cm to 3000 cm/cm. TIME SCALE: 20 to 200 nsec/cm, +5% accuracy. MAGNIFICATION: X1 to Z O O in 1,2,5 sequence. Accuracy of the basic sweep is maintained at all magnifier setting$ with the exception of time represent

32、ed by the first 0.1 cm of the unmagni- fied sweep after start of the step. sweep, calibrated. Display): 5%. to 2000 cm/cm. DELAY CONTROL: 0 to 10 cm of unmagnified JITTER: Less than 20 psec. ACCESSORIES F U R N I S H ED DESCRIPTION QUANTITY GR Elbow (EL connector) 2 GR to type N adapter BNC to type

33、N adapter 1 1 P O W E R W E I G H T Supplied by 0 scilloscope. Net, 7 lbs. (3,2 kg). 1-0 01944-9 Model 1415A WWW.HP.9RCHWE.COM For Free Distribution Only Sections I and I1 Paragraphs 1-1 to 2-6 1-1. DESCRIPTION. SECTION I GENERAL I N F O R M A T I O N 1-2. The Model 1415ATimeDomainReflectometer, a d

34、ouble-size plug-in unit for the Model 140-series Oscilloscopes, is a completely integrated transmission line testing system. The unit includes both the time base and vertical deflection functions of a high-speed sampling oscilloscope, and a fast-rise step generator. The Model 1415A locates and deter

35、mines the magni- tude and nature of discontinuties in high-frequency transmission sytems, andcan be used to measure the quality of broad band systems. 1-3. The technique of time domain reflectometry, for which the Model 1415A is specifically designed, consists essentially of applying a voltage step

36、to the transmis- sion system and observing the reflections. A reflec- tion occurs each time the step encounters animpedance mismatch (discontinuity); this reflection is added to the incident wave and is displayed on the CRT of the oscil- loscope. The time requiredfor the reflection to return to the

37、sampler in the Model 1415A locates the discon- tinuity. The shape and magnitude of the reflected wave indicate the nature and value of the mismatch, which can be resistive, inductive, or capacitive. In general, an inductive discontinuity reflects a voltage spike having the same polarity as the incid

38、ent step, and a capacitive discontinuity reflects a voltage spike of the opposite polarity. A resistive discontinuity having a value larger than the line impedance reflects a step of the same polarity as the incident step, and a step of the opposite polarity is reflectedif the value is less than the

39、 line impedance. Detailed discussions on evaluat- ing reflections observed are given in Application Notes 62 and 67, which are supplied with the Model 1415A. 1-4. OPTIONS. 1-5. There is oneoptionavailable for the Model 1415A. This option (Option 14) provides an additional position for the DISTANCE/T

40、IME switch. This addedposition is equal to 1000 nsec/cm expressedin time, or 10,000 CM LINE/CM DISPLAY (polyethylene) and 15,000 CM LINE/CM DISPLAY (air) expressedindistance. Re- fer to Appendix I for complete information on this option. 1-6. MANUAL IDENTIFICATION. 1-7. Information in this manual ap

41、plies directly to Model 1415A instruments with a serial prefix of 622 or 623 (see manual titlepage). The serialprefix of a instrument is the first three digits (i. e. those before the dash, as 000-00000) of the serial number stamped on a plate attached to the rear panel. Appendix I1 contains informa

42、tion on changes required to adapt this manual to aninstrumentwith the serialprefixes listed. 1-8. SCOPE OF MANUAL. 1-9. This manual supplies operating and maintenance instructions for the Model 1415A TimeDomainReflect- ometer. The information in this manual supplements the manual for the oscilloscop

43、e with which the Model 1415A is used. Refer to the Oscilloscope manual for specifications and instructions which apply specifi- cally to that instrument. SECTION II I N STA LL AT1 0 N 2-1. INITIAL INSPECTION. 2-2. MECHANICAL CHECK. If external damage to the shipping carton is evident, ask the carrie

44、rs agent to be present when the instrument is unpacked. Check the instrument for external damage such as broken controls or connectors, and dents or scratches on the panel surface. If damage is evident, see Paragraph 2-4 for recommendedclaimprocedure and repackaging information. I f the shipping car

45、ton is not damaged, check the cushioning material and note any signs of severe stress as anindication of rough handling in transit. If the instrument appears undamaged, per- form the electrical check (see Paragraph 2-3). 2-3. ELECTRICAL CHECK. Check the electrical performance of the Model 1415A as s

46、oon as possible after receipt. Paragraphs 5-3 through 5-17 contain performance check procedures which will verify in- 01944- 4 strument operation within the specifications listed in Table 1-1. This check is also suitable for incoming quality control inspection. If the Model 1415A does not perform wi

47、thin the specifications when received, refer to Paragraph 2-4 for recommended claim pro- c edu r e and repackaging information. 2-4. DAMAGE CLAIM AND REPACKAGING. 2-5. If physical damage is evident, or if the instru- ment does not meet specifications when recieved, noti- fy the carrier and the neare

48、st Hewlett-Packard Sales/ Service Office (see list at rear of this manual). The Sales/Service Office will arrange for repair or replace- ment without waitingfor settlement of aclaim with the carrier. 2-6. The originalshipping carton and packing material, with the exception of accordion-pleated pads,should be 1-1 2-1 Section I1 Paragraphs 2-7 and 2-8. used