krohnhite 35 Manual 电路图.pdf

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1、Model 35 170Hz to 25.6MHz, 24dB/Octave Butterworth Tunable Active Plug-In Filter Card Operating Manual RadioFans.CN 收音机爱 好者资料库 Service and Warranty Krohn-Hite Instruments are designed and manufactured in accordance with sound engineering practices and should give long trouble-free service under norm

2、al operating conditions. If your instrument fails to provide satisfactory service and you are unable to locate the source of trouble, contact our Service Department at (508) 580-1660, giving all the information available concerning the failure. DO NOT return the instrument without our written or ver

3、bal authorization to do so. After contacting us, we will issue a Return Authorization Number which should be referenced on the packing slip and purchase order. In most cases, we will be able to supply you with the information necessary to repair the instrument, avoiding any transportation problems a

4、nd costs. When it becomes necessary to return the instrument to the factory, kindly pack it carefully and ship it to us prepaid. All Krohn-Hite products are warranted against defectivematerials and workmanship. This warrantyappliesforaperiodofoneyearfromthedateofdeliverytotheOriginalPurchaser. Any i

5、nstrument that is found within the one year warranty period not to meet these standards, will be repaired or replaced. This warranty does not apply to electron tubes, fuses or batteries. No other warranty is expressed or implied. Krohn-Hite Corporation reserves the right to make design changes at an

6、y time without incurringanyobligationtoincorporatethesechangesininstrumentspreviouslypurchased. Modifications to this instrument must not be made without the written consent of an authorized employee of Krohn-Hite Corporation. RadioFans.CN 收音机爱 好者资料库 MODEL 35 170Hz to 25.6MHz LOW-PASS BUTTERWORTH PL

7、UG-IN FILTER CARD OPERATING AND MAINTENANCE MANDL . PLUG- IN FILTER CARDS MODEL SIN MODEL SIN MODEL SIN MODEL SIN MODeL SIN MODEL SIN MODEL SIN MODEL SIN MODEL SIN MODEL SIN MODE/. SIN MODEL SIN MODEL SIN MODEL SIN MODEL SIN MODEL SIN I.FL.IKRCHN-HITE COFlPOFl.A.TION 255 Bodwell Street, Avon , MA 02

8、322-9987 Tel: (508)580-1660; Fax: (508)583-8989 RadioFans.CN 收音机爱 好者资料库 Table of Contents Model 35 Table of Contents 1.0 GENERAL DESCRIPTION 1-1 1.1 INTRODUCTION 1-1 1.2 SPECIFICATIONS 1-1 1.2.1 Filter Ch arac te rist ics 1-1 1.2.2 Input 1-1 1.2.3 Output 1-2 1.2.4 General 1-2 2.0 OPERATION 2-1 2.1 I

9、NTRODUCTION 2-1 2.2 TURN-ON PROCEDURE 2-1 2.3 SELF-TEST fEATURE 2-1 2.4 JUMPER SETTINGS FOR FRONT AND REAR PANEL OPERATION 2-2 2.5 FRONT PANEL CONTROLS AND DISPLAY 2-2 2.5.1 Data Keys 2-2 2.5.2 MODE Key 2-2 2.5.3 TYPE Key 2-2 2.5.4 Channel 2-2 2.5.5 Gain Set 2-2 2.5.6 Input Overload 2-2 2.5.7 Output

10、 Overload 2-2 2.5.g ICE Clear Entry Key 2-3 2.5.9 lALL CHANNEL Key 2-3 2.5.10 Input Ohms (Labeled White) 2-3 3.0 IEE-488 STn (GPID) PROGRAMMING 3-1 3.1 INTRODUCTION 3-1 3.2 FILTER TYPE 3-1 3.3 MODE OF OPERATION 3-1 3.4 DEVICE CLEAR 3-1 4.0 INCOMING ACCEPTANCE 4-1 4.1 INTRODUCTION 4-1 4.2 TEST EQUlPM

11、ENT REQUIRED 4-1 4.3 INITIAL SETTINGS 4-1 4.4 DC OUTPUT LEVEL CHECKS 4-1 4.5 GAIN ACCURACY CHECK 4-2 4.6 DISTORTION CHECK 4-2 4.7 SQUAREWAVE RISE AND FALL TIME CHECK 4-2 4.8 FREQUENCY CALIBRATION CHECK 4-2 4.9 WIDEBAND NOISF CH ECK 4-3 4.10 STOPBAND ATTENUATION CHECK 4-3 Model 35 Table of Contents i

12、i Table of Contents Model 35 Model 35 Plug-In Filter Card iii Moclel35 Section 1 - General Description SECTION 1 GENERAL DESCRIPTION 1.1 INTRODUCTION The Model 35 is a low-pass, Butterworth (maximally flat) filler card, used in the Models 3905B and 3916B mainframes, providing 24GB/octave rolloff wit

13、h a minimum stopband attenuation of up to lOOdB. The Model 35 covers the frequency range of 170Hz to 25.6MHz with 2Vzdigits of resolution. The filter card has selectable AC or DC coupling and selectable 1M or 50 ohm impedance. Programmable input gains of up to 20dB and output gains of up to 26dB are

14、 standard. The Mode135 also has the capability to be configured in an Amplifier By-Pass mode to operate as an amplifier, by-passing the filter. This gives the user the ability to amplify without filtering when so desired. The Model 35 is one of many Krohn-Hite filter cards used in conjunction with t

15、wo GPIB programmable mainframes; the 3 1/2 high Model 3905B (5 plug-in card chassis) or the Model 3916B (16 plug-in card chassis). 1.2 SPECIFICATIONS 1.2.1 FILTER CHARACTERISTICS Filter Type: 4-Pole, Butterworth, Low-Pass. Tunable Cutoff Frequency Range: 170Hz (0 25.6MHz. Frequency Response: FreQuen

16、cy Range Resolution 170Hz 0 2.56kHz 10Hz 2,6kHz to 25.6kHz 100Hz 26kHz to 256kHz 1kHz 260kHz to 2,56MHz 10kHz 2.6MHz 0 25.6MHz 100kHz Cutoff Frequency Accuracy: 2% to 2.56MHz, =5% to 25.6MHz. Attenuation Slope: 24dB/Octave. Stopband Attenuation: 100dB to 1MHz, 80dB at 1OMHz,70dB at 30MHz, 60dB at 50

17、MHz, 50dB to lOOMHz. Amplified Bypass Mode Bandwidth: 50MHz. Amplified Bypass Mode Rise and Fall Time: 7ns with OdBinput gain 6dB output gain, IOns with +20dB input or output gain. -6O1B below signal up to 100kHz (0.1%). Allharmonics below 50dB to 1MHz; below 40dB above 1MHz. Output DC Offset: Adjus

18、table to Zero. Output DC Offset Drift: 0.5mVtC referred to input. NoiseSpectral Density(10kHz to l00MHzreferred to input):Below-128dBmlHzinto 50 ohms. This translates into a wideband noise power or voltage for a 30MHz BW of below -53dBm or O.50mVrms referred to input. Spurious Signals: Below -80dBm

19、to 65MHz; below -75dBm to l00MHz. Referred to input, represented in voltage form: 22J.lV and 40.uV respectively. 1.2.4 GENERAL Input/Output Connectors: BNe. Power: 8 watts. Weight 1.75 lbs, (.8kg) net. Operating Temperature: OC to 50e. Specifications apply at 25C 10C, Specifications subject to chang

20、e without notice. NOTE: The Model 35filter card must be used with the Model 39058 or 39168 mainframes. 1-2 Model 35 Section 2 - Operation SECTION 2 OPERATION 2.1 INTRODUCTION The Model 35 low-pass filter card covers the frequency range from 170Hz to 25.6MHz. It is one of a series of filter cards ava

21、ilable for the 5 plug-in card mainframe, Model 3905B or the 16 plug-in card mainframe, Model 3916B mainframe. All filter parameters are programmable via the mainframes front panel or remotely over the IEEE-488 (GPIB) bus. For detailed information of the front panel controls and remote programming. r

22、efer to Section 2 and 3 of the Model 3905N/3916B mainframes Operating and Maintenance Manual. Section 2.4 of this manual briefly describes the operation of the principal front panel controls and data key operation. 2.2 TURN- ON PROCEDURE a. The line voltage range of the Model 3905B/3916B mainframe h

23、as been preset at the factory for either 115V or 230V operation. This range switch is located internally if a line voltage change is required. Check to see that a fuse with the correct rating is in the fuse receptacle. b. Make certain that the POWER switch on the front panel of the unit is in the OF

24、F position. c. Plug the line cord into the unit first, then into an ac outlet. CAUTION .:.:. :. .,.;. ,:. For safety purposes, the line cord must be connected to a grounded 3-tenninal ac outlet. Because ofpotentially dangerous voltages thai exist within the mainframe, the covers should be removed on

25、ly by qualified personnel. d. If the Model 3905B/3916B is remotely programmed via the IEEE-488 (GPIB) bus, connect the bus cable to the rear panel 24 position D connector at this time. Programming information is provided in Section 3 of the Model 3905B/3916B Operating and Maintenance Manual, with ad

26、ditional information in Section 3 of this manual. e. The POWER switch is a toggle type, located on the front panel of the Model 3905B/3916B. After familiarizi ng yourself with the self-test feat ure described next, turn-on the Model 3905B/3916B. 2.3 SELFTEST FEATURE When turned 0 n,theModel3905B/391

27、6B mieroproccssor pcrftirrnsa Scif-Tcst routine wherebytheen tire RAM and ROM operation is verified. During the test, the front panel LEDs and display will light up sequentially. If there is a malfunction in the microprocessor, such as a defective RAM or ROM. the sequence will stop and the word bAd

28、will appear in the display, followed by a number from 1 to 3. Refer to Section 7.6, Digital Circuit Maintenance, to find which RAM or ROM isdefective; otherwise, when the Self-Test program is complete, the Model 3905B/3916B will return to the last set-up prior to turning off the unit. The Model 3905

29、B/3916B is now ready to be programmed for operation. 2-1 Section 2 - Operation Model 35 2.4 JUMPER SETIINGS FOR FRONT AND REAR PANEL OPERATION Toachieve clean high frequency signal performance from the rear panel input and output ENCs, it is necessary to disconnect the cabling connecting the front p

30、anel ENCs by moving the two jumpers on jumper blocks J201 (for input) and J517 (for output) shown in Figure 2.1 below. The Model 35 filter cards are shipped with the jumpers set with front panel BNG; active. REAR ONLY FRONT either e50.; DC INPUT OHMS 50 Ohms 3-1 Section 3 - IEEE-488 STD (GPfB) Progr

31、amming Model 35 This page intentionafly left blank. 3-2 Model 35 Section 4 - Incoming Acceptance SECTION 4 INCOMING ACCEPTANCE 4.1 INTRODUCTION The following procedure should be used to verify that the Model 35 filter card, inserted in a Model 3905B or 3916B mainframe, is operating within specificat

32、ions. These checks may be used (or incoming acceptance and periodic performance checks. Tests must be made with all covers in place and operating (or a minimum time of 112 hour to reach thermal equilibrium. If not operating within specifications, refer to Section 5, Calibration, before attempting an

33、y detailed maintenance. Before testing, follow the initial set-up and operating procedure in Section 2 of this manual and the Model 3905B/3916B Operating and Maintenance Manual. 4.2 TEST EQUIPMENT REQUIRED The test equipment below is required to perform the following tests: II. DC Voltmeter (DVM), c

34、apable of measuring 1mV to 20Y; Fluke 8000 or equivalent. b. AC RMS Voltmeter, capable of measuring 100.uV to 10Vrms and useful bandwidth to 25MHz, Fluke 8920A or equivalent. c. Squarewave Source ,2Vp-p squlrewave with rise and fall times 50S with 5% overshoot or ring, HP8012B or equivalent. d. Low

35、Distortion Sinewave Signal Source, 0.05% distortion to 100kHz, 0.1% to 1MHz, Krohn-Hite Model 4200B or equivalent. e. Distortion Analyzer. capable of measuring distortion to 1MHz, Krohn-Hite Model 6900B or equivalent. f. Sinewave Signal Source, covering the frequency range from IMHz to 1ooMHz, Tektr

36、onix Model 191 or equivalent. g. Spectrum Analyzer, HP Model tatTwith RF section 8553B and IF section 8552B or equivalent. h. Oscilloscope, lOOMHz bandwidth, Tektronix Model 2245A or equivalent. 4.3 INITIAL SETTINGS Input ohms: 50 Input Gain: OdB Input Coupling: DC Cutoff Frequency: 10MHz Output Gai

37、n: GdB Overload Mode: 2 FiIter Mode: LP NOTE: Good high frequency techniques should be used at all times, which includes the use ofgood qualily 50 ohm cabling for signal connections to and from the jilter: 4.4 DC OUTPUT LEVEL CHECKS Connect the DVM set for DC operation to the filter Output. Measure

38、DC level for all Input and Output gain settings. Should be lOmVdc. 4-1 Section 4 -Incoming Acceptance Model 35 4.5 GAIN ACCURACY CHECK Disconnect the DVM and connect the Fluke 8920A to the filter Output. Connect a 0.1Vrrns, 1kHz signal to the input (note that the filter Input is set for 50 ohms and

39、will terminate a 50 ohm source producing a factor of2less in amplitude). Set the filter Output gain for OdB. Set the Fluke 8920A for AC relative dB measurements, and zero reference the Fluke. Check each Input and Output gain selling by switching each one up from OdB independently. All dB readings sh

40、ould be within O.ldB of the filter gain setting. 4.6 DISTORTION CHECK Disconnect the Fluke 8920A from the filter Output. Set the filter for OdB Input gain and 6dB Output gain. Set the signal source for 1Vrrns, 1kHz, sincwavc and connect to the filter Input. Connect the Distortion Analyzer to the lil

41、ter Output through a 50 ohm cable terminated at the analyzer end. Measure the distortion at the following frequencies: Frequency Tolerance 1kHz 0.1% 100kHz 0.1% 1MHz 0.3% If necessary, verify that the signal sou rces distortion is below the above readings by measuring it separately. 4.7 SQUAREWAVE R

42、ISE AND FALL TIME CHECK Disconnect the distortion analyzer and sinewave signal source from the filter. Set the filter for GAIN mode. The filter Input and Output gain should be OdB and 6dB respectively, and Inpul Ohms set to 50. Set the filter coupling to AC. Connect the niter Input using a 50 ohm ca

43、ble to the squarewave source set for 2Vp-p, 2.5MHz, squarewave. Connect the filter Output to an oscilloscope with a 50 ohm cable terminated at the oscilloscope end. Observe on the scope that overshoot and ringing is 5%. Measure the rise and fall time from the 10% and 90% waveform points. It should b

44、e 7ns. Set the squarewave source for 0.2Vp-p. Check the Output waveform first with 20dB Input gain and then with 26dB Output gain for 5% overshoot and ringing, and 10ns rise and fall time. 4.8 FREQUENCY CALIBRATION CHECK Set the filter for the initial setting at the beginning of this Section. Connec

45、t the filter Input via a 50 ohm cable to a 1Vrms, 1kHz, sinewavc signal source. Connect the Fluke 8920A to the Output of the filter with a 50 ohm cable. Set the Fluke for relative dB operation. Set the filter for a cutoff frequency of 1kHz and GAIN mode. Zero reference the Fluke. Set the filter for

46、LOW-PASS (LP) mode and measure the drop in dB on the Output. It should be within -2.67dB to -3.37dB for a 2% calibration range. 4-2 Model 35 Section 4 - Incoming Acceptance Set the sinewave generator and filter cutoff to the following frequencies and zero referencing the Fluke in the filter GAIN mod

47、e, measure the drop in gain on the Output of the filter when switching the filter to the LP mode. Freguency dB at Cutoff Range % Error Spec 1kHz -2.67dB to -3.37dB 2% 10kHz -2.67dB to -3.37dB 2% 100kHz -2.67dB to -3.37dB 2% 1MHz -2.67dB to -3.37dB 2% 10MHz -2.21 dB to -3.94dB 5% 4.9 WIDE BAND NOISE

48、CHECK Set the filter for 25.6MHz, LP mode, OdB Input gain and 26dB Output gain . Disconnect the sinewavc signal from the filter Input. With the Fluke connected to the Output via a 50 ohm terminated cable, measure the wideband noise voltage present. Wideband noise should be 5mV which translates to SO

49、O,uV referenced to the Input, since the net gain from the filter Input to the meter is 2OdB. 4.10 STOPBAND ATTENUATION CHECK NOTE: This test uses a SpeCll1lnl analyzer to detect the rejected signal. Most spectrum analyzers have a maximum signal amplitude wuhout damage limu. Care should be taken hat this signal level limit is not exceeded: A simple precaution would be