HP 423A Crystal Detector

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HP 423A Crystal Detector Errata Title & Document Type: 423A and 8470A Crystal Detector Operating and Service Manual Manual Part Number: 00423-90001 Revision Date: July 1976 About this Manual We’ve added this manual to the Agilent website in an effort to help you support your product. This manual provides the best information we could find. It may be incomplete or contain dated information, and the scan quality may not be ideal. If we find a better copy in the future, we will add it to the Agilent website. HP References in this Manual This manual may contain references to HP or Hewlett-Packard. Please note that Hewlett- Packard's former test and measurement, life sciences, and chemical analysis businesses are now part of Agilent Technologies. The HP XXXX referred to in this document is now the Agilent XXXX. For example, model number HP8648A is now model number Agilent 8648A. We have made no changes to this manual copy. Support for Your Product Agilent no longer sells or supports this product. You will find any other available product information on the Agilent Test & Measurement website: www.agilent.com Search for the model number of this product, and the resulting product page will guide you to any available information. Our service centers may be able to perform calibration if no repair parts are needed, but no other support from Agilent is available. OPERATING AND SERVICE MANUAL - I 423A 8470A CRYSTAL DETECTOR HEWLETT~PACKARD Plint.d: JUtY 191& e H.",len Packard Co. \910 1 " • .' • I .... ,. ", - \, . '. ~ ~.. ". ." , .' " . ..... " 'I. "",:,. • ' Page 2 i\lodel ·123A/8470A 1. GENERAL INFORMATION 10. INSTALLATION 2. This manual contains operating instructions for 11. Initial Inspection e the Hewlett-Packard Model ·123:\ and 8470:\ Crys­ 12. Inspect the shipping container for damage. If tal Detectors. Included ill the manual is the inform­ the shipping container or cushioning material is ation required to install and test the crystal damaged, It should be kept until the contents of the detectors. shipment have been checked for completeness and the instrument has been checked mechanically and 3. On the rear cover of this manual, below the electrically. manual part number. is a "Microfiche", part nurn­ ber, This number may be used to order a ·1 x 6· 13. The procedures for checking electrical perfor­ inch microfilm transparency of the manual. mance are given under PERFORMANCE TESTS. If the contents are incomplete, if then' is mechanical 4. Specifications damage or defect. or if the instrument does not pass the electrical performance test, not.Iy the nearest 5. Instrument specifications are listed in Table 1. Hewlett-Packard office. If the shipp"'"'''' "rid is These specifications are the performance standards, damaged. or the cushioning material ~l'",'.;, ·;gn~ of or limits against which the instrument may he tested. stress. notify the carri-r as well as the Hewlett­ Packard office. Keep the shipping materials for the 6. Description carrier's inspection. The liP office will arrange for repair or replacement at liP', option without wait­ 7. The Hewlett-Packard Modd ·12.1:\ and 8470A ing for claim settlement. Crystal Detectors are 50!! (nominal) device, de­ signed for measurement use in coax ial systems. The 14. Mating Connectors instruments convert IH' power levels applied to the 50\! input connector into proporr.ona: values of 15. Tile 8nOA (standard] RF input connector de voltage. The instruments measure relative pow-r must be an APC·7 type connector. The mating RF input connectors used with the ·123A and up to 100 mW and have a BNC femaie connector for the output jack which a!:ows the detected out­ 8·17CA Option 012 must be Type N female conner- • put to be eonrr-cted to a SWR meter. The output tors which comply with U.S. military standard voltage polarity is negative, unless Option 003 is :\IIL·C·39012. The mating RF input connector selected, The frequency range of the 423:\ is used with the 8-nOA Option 013 must be Type N 10 i\lIIz to 12.4 Gllz. Tne 8·170:\'s frequency ranje male connector which complies with i\IIL-C·3!l012. extends from 10 Mllz to 18 ellz. 16. Operating Environment 17. The operating environment 01 the crystal de­ 8. Options tectors should be within the following lirnit.vtions: 9. The 423A and 8470A Crystal Detectors are a. Temperature: 0' to +55" C available with the following options (see Table 1 b. Altitude: -, -1572 metres 115.000 feet] for further descnptions): Option 001: Matched pair of detectors c. fll,midi~,j.··", 95':;; relative. Option 002: Furnished with matched 10a,I reo sister (liP 115'23Al for optimum 18. STORAGE t'.NO SHIPMENT square law characteristics 19. Env;ronmer.l. Til, inst..urnent should be stored Option 003: Positive polarity output ir, a clean, cl4'.)' environment. The following environ­ Option 012: Furnished with stainless steel mental limitations apply to both storage arod type N male connectors (8470A shrprnent: only). 3_ Temperature: -20'C to +55'C Option 013: Furnished with stainless steel type N fem<lle connectors 18-170A b. Altitude: <762" metres t25.000 Ieet ) only). C'~ Humidity: <95'i'f: relative. • • J ~ • J .. c' ..' '1, • "• .,,"t~··, ~ • ' • 1 "\'1 ," I''', • \ • " '\'..... "'l'I!'" .• 'r'·),. I,• • ' '.' r .' ' I, / •• , ( '. ~ .. ' ••" ~," • \~ I' .... '," "~·il., , :, ~,,~ • .;', .. ""ill '" .:.' .,'~ .~. ;~ /'., "",. ,. , .'. -.' t'" ~ I j. ~ ~\ _ J' • .' '. \ .. , ( l ,,' , ,t • ~ _ .. .' Page 4 :'.Iodel ,123A:8470A 20. Original Packaging. Containers and material> degradation of rise time. identical to those used in factory packaging are available through Hewlett-Packard offices. If the 25. The power applied to the detector can be either instrument is being returned tc Hewlett-Packard modulated or continuous wave ~CWi. If modulated at a 10:)0 Hz rate, an SWR meter can be used as an • for servicing, attach a tag indicating the type of service required, return address, model number, indicator. For CW detection. a dc milliammeter or and serial number. Also, mark the container f'RA­ millivoltmeter can be used as the indicator. G!LE to assure careful handling. :n any corres­ pondence, refer to the instrument by model num­ 26. Operator's Checks ber and serial number. 27. Peak Power Measurement. The arrangement of equipment for peak power measurement is shown 21. OPERATION in Figure 1. The procedure involves calibration of an oscilloscope which, in turn, is used to calibrate a ICAUTION I CW generator. The output of the calibrated CW generator is measure with a power meter; the peak Static discharge can damage the detector power of a pulse is thereby measured. The proce­ element. A 100 pF ccpacitor (1.2 m{4 dur e is as follows: [t.] ofcoax cabld charged to 14 volts stores 0.1 erg, the maxim11m pulse rating a. Connect equipment as shown in Figure 1. of the deicelor element. Connect cables step a. Observe pulse on a de-coupled oscilloscope. ro '"H equipment and di..chargc the cen­ Using a marking pencil. mark en the graticule the re. mductor before ,..:nnecling to the base-to-peak amplitude of the pulse envelop.'. ietector. b. Replace the pulse source with a CW gen­ DO NOT NEEDLESSL r llANDLE DE· erator. Whileobserving t.he oscilloscope trace. ad­ TECTOR ELEMEI"T USElllN CR YS· just amplitude of CW generator output to make de­ TAL DETECTOR. Static electricity tector's output equal \0 that of pulse generator. which builds up on II person, especial­ as indicated by markings on graticule (step a). lyon a cold dry day, m1l.t ne;:er be atlouied 10 discharge thro1lgh the crys­ c. Leave CW generator at setung obtained tal detector. Avoid exposed leads 10 or in step b. Disconnect detector from CW generator. from the crystal detector, since these are often touched accidentalty, STEP@ PULSE OSCILLOSCOPE 22. Operating Inlormation SOuRCE 23. The crystal cetector can be used as a demodu­ f.. 1i]l\" .. lator to obtain a pulse envelope which can then he L'" \LI:!Y observed on an oscilloscope. It can also be used as CR'1$TAL DE. rECTOR -rVERTICAl a general purpose detector. -0: STEp0 24. When wing the crystal detector with an oscil­ CONTINUOUS wAVE loscope, and the waveshapes to be observed have GENERATOR rise limes of less than 5 J.lS, the coaxial cable cr .1, necting oscilloscope and detector should be as short as possible and shunted with a resistor. Ideal­ Iy, this resistor should be 50l! to terminate the coaxial cable properly. However, wi~h 50l! resis­ powER METER tance, the output video pulse may be too small to drive some oscilloscopes. Therefore. the cable CONTINUOUS W"'\iE should be shunted with the smallest value of resis­ G::NERJ.TOR 11~01 tance that will obtain suitable deflection on tile THERMI$TOq MOUN_r_ : 11 • oscilloscope; typically the value will lie between 5011 and 2 kn. The larger the resistance the more • .), , '.' ", ".' ~'. ••• ~ ~." • ~ • • , • > ," ~ ,. ~ t' ~l' r \ "<1'J"., ~ " , 'I •.' , - .. ' • J'• • • ' ••• .' " • I • .' '. • • • Model 423A/8410..\ Page 5 Connect output of CW generator to power meter. 33. High level Sensitivity Test Measure adjusted levels (set in step b) of CW gener­ a. Using si, nal sources covering 10 ;',lIIz to ator output. The peak power of the pulse en. rlope 18 Gllz and a de voltmeter or osci.ioscope as the observed in step a is equal to the output power of indicator, connect detector to signal source. Ad 4 the CW generator. just Rf' power lewI for a 100 mV detected output from detector. 28. Rellectometer Application. For information about rel1ectometer systems and measurements. b. Disconruct detector from signal source see flP Application Note Index, copies of which -md measure RF output level. The Rf' output are available upon request. level should be <;; 0.35 roW.
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