krohnhite 34A Manual 电路图.pdf

Model 34A 3Hz to 2MHz 2-Channel Butterworth/Bessel HP, LP, BP, BR Plug-In Filter Card for Model 3905/3916 Chassis 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 normal 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. DONOTreturntheinstrumentwithoutourwrittenorverbalauthorizationtodoso.Aftercontactingus,we will issue a Return Authorization Number which should be referenced on the packing slip and purchase order. In mostcases, wewill beable to supply youwith the information necessary to repair the instrument, avoidinganytransportationproblemsandcosts.Whenitbecomesnecessarytoreturntheinstrumenttothe factory, kindly pack it carefully and ship it to us prepaid. All Krohn-Hite products are warranted against defective materials and workmanship. This warranty applies for a period of one year from the date of delivery to the Original Purchaser. Any instrument 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 any time without incurring any obligation to incorporate these changes in instruments previously purchased. Modificationstothisinstrumentmustnotbemadewithoutthewrittenconsentofanauthorizedemployeeof Krohn-Hite Corporation. RadioFans.CN 收音机爱 好者资料库 Model 34A Plug-In Filter Card 1 MODEL 34A DUAL CHANNEL/BUTTERWORTH/BESSEL LOW-PASS/HIGH-PASS/BAND-PASS/BAND-REJECT PLUG-IN FILTER MODULE OPERATING MANUAL Serial No. Serial No. 15 Jonahtan Drive, Brockton, MA 02301 Tel: (508) 580-1660; Fax: (508) 583-8989 E-mail: I; www.krohn- RadioFans.CN 收音机爱 好者资料库 Model 34A Plug-In Filter Card 2 Model 34A Plug-In Filter Card 3 TABLE OF CONTENTS 1.0 GENERAL DESCRIPTION. 5 1.1 INTRODUCTION.5 1.2 SPECIFICATIONS .5 2.0 OPERATION . 7 2.1 INTRODUCTION.7 2.2 OPERATING PROCEDURE.7 2.2.1 Channel Selection.7 2.2.2 All Channel Key Procedure.7 2.2.3 Cutoff Frequency .7 2.2.4 Input Gain (Pre-Filter).7 2.2.5 Output Gain (Post Filter).7 2.2.6 Mode of Operation.8 2.2.7 Filter Type.8 2.2.8 Input Coupling.8 2.2.9 Clear Entry Key Operation.8 2.2.10 Storing Set-Ups.8 2.2.11 Recalling Set-Ups.9 2.2.12 Second Function Key Operation.9 2.3 FILTER CHARACTERISTICS.9 2.3.1 Introduction.9 2.3.2 Variable Band-Pass and Band-Reject Operation.9 2.3.3 Amplitude Response.10 2.3.4 Phase Response.11 2.3.5 Group Delay.11 2.3.6 Transient Response.11 3.0 IEEE-488 STD (GPIB) PROGRAMMING. 13 3.1 INTRODUCTION.13 3.2 FILTER TYPE .13 3.3 MODE OF OPERATION .13 3.4 DEVICE CLEAR.13 4.0 INCOMING ACCEPTANCE . 15 4.1 INTRODUCTION.15 4.2 TEST EQUIPMENT REQUIRED.15 4.3 FILTER CHARACTERISTICS.15 4.3.1 Low Pass/High Pass Response.15 4.3.2 Cutoff Frequency Accuracy.16 4.3.3 Band-Pass/Band-Reject Response .16 4.3.4 Stopband Attentuation*.17 *(This procedure requires a Fluke Model 8920A voltmeter) 4.3.5 Pre-Filter and Post-Filter Gain Accuracy .17 4.3.6 Noise Check (This procedure requires a Fluke Model 8920A voltmeter) .18 4.3.7 Distortion and Maximum Signal Checks.18 4.3.8 AC/DC Coupling Check .19 Model 34A Plug-In Filter Card 4 NOTES Model 34A Plug-In Filter Card 5 SECTION 1 GENERAL DESCRIPTION 1.1 INTRODUCTION The Model 34A is a dual filter with two identical channels covering a tunable frequency range from 3Hz to 2MHz. Each channel can function independently with either low-pass or high-pass response at 24dB/octave attenuation or connected in series in the same mode to provide 48dB/octave attenuation. Band-pass or band-reject operation at 24dB/octave can be obtained. Either maximally flat (Butterworth) response or linear phase (Bessel) operation for pulse signal filtering is selectable. Both input and output amplifiers provide either 0dB or 20dB of gain. The Model 34A is a plug-in filter card which is operational only when inserted in the five-card Model 3905A/3905B/3905C or the sixteen-card Model 3916A/3916B/3916C Mainframe. Each Mainframe includes a microprocessor plug-in card; the Model 39A-05 for the 3905A/3905B/3905C, and the 39A-16 for the 3916A/3916B/3916C. The filter and microprocessor cards are easily accessible from the rear of the Mainframe. The filer is controlled by the Mainframe which provides local/IEEE-488 programming, displays for the input and output gain, cutoff frequency and channel selection. Non-volatile, battery- backed, CMOS memory permits the storing and recalling of 85 selectable groups in the 3905A/3905B/3905C and 25 in the 3916A/3916B/3916C. Storing and recalling group settings is accomplished with only one command. Self-testing of the digital circuitry occurs upon power-up. This Operating and Maintenance Manual is for the Model 34A filter module only. A separate manual is provided for the Model 3905A/3905B/3905C or 3916A/3916B/3916C Mainframe. 1.2 SPECIFICATIONS FILTER CHARACTERISTICS Functions: two independent channels of low-pass, high-pass or by-pass; one channel of band- pass or band-reject. Type: 4-pole Butterworth (maximally flat) or Bessel (linear phase). Frequency Range (fc): 3Hz to 2MHz Frequency Resolution: 1Hz from 3Hz to 1kHz; 10Hz up to 2kHz; 100Hz up to 100kHz; 1kHz up to 1MHz; 10kHz up to 2MHz. Frequency Accuracy (fc): 2% or least significant digit (which ever is greater) 20Hz to 500kHz; 5% to 2MHz. Relative Gain at fc: Butterworth, -3dB; Bessel, -7.58dB. Bandwidth: dc to fc, dc coupled; 0.2HZ to fc, ac coupled (low-pass); fc to 10MHz (high-pass). Attenuation: 24B/octave per channel. Stopband Attenuation: 80dB. Insertion Loss (0dB Input/Output gain): 0.5dB to 2MHz. Model 34A Plug-In Filter Card 6 GAIN Input (pre-filter): 0dB or 20dB 0.2dB. Output (post-filter): 0dB or 20dB 0.2dB. INPUT Coupling: ac or dc. Impedance: 1 megohm in parallel with <30pf (<100pf in a Model 3905B with front panel BNCs). Maximum Signal (at 0dB gain): 4.5V peak at fc 500 ohms; 1.3V peak into 50 ohms. Maximum Current: 25mA. Distortion: -80dB at 1kHz at 1V rms. Noise (RTI): <200V with 2MHz bandwidth detector (20V w2ith 20dB input gain). DC Offset: adjustable to 0V. DC Stability: 1mV/C. Input/Output Connectors: BNC. Phase Match Between Channels*: 1 to 500kHz fc (Bessel only); 2 to 1MHz; 3 to 2MHz (max difference between any two channels). GENERAL Power: 15 watts. Weight: 1.75 lbs. (0.8kg) net. Operating Temperature: 0 to 45C. Specifications apply at 25C 10C, 20Hz to 2MHz. *For cards in same chassis, otherwise consult factory. Model 34A Plug-In Filter Card 7 SECTION 2 OPERATION 2.1 INTRODUCTION The Model 34A is a dual filter covering the frequency range from 3Hz to 2MHz. It is one of a series of plug-in filter cards available for the five-card Model 3905A/3905B/3905C or the sixteen-card Model 3916A/3916B/3916C Mainframes. All filter parameters are programmable via the Mainframe front panel controls or remotely over the IEEE-488 (GPIB) bus. For information on remote programming, refer to Section 3 of the Model 3905A/3905B or 3916A/3916B Operating and Instruction Manual and Section 3 of this manual. Either channel of the 34A can operate independently in either the low-pass or high-pass mode and provide 24dB/octave attenuation. The two channels can be connected in series externally in the same mode to attain 48dB/octave attenuation when set to the same cutoff frequency. If the two channels are interconnected externally with one channel set to high-pass and the other to low-pass, the filter will now function as a band-pass filter, passing the band of frequencies selected by the high and low cutoff frequencies. If the two channels are interconnected externally using a band-reject kit (BR-30), the filter will then function as a band-reject filter, rejecting the band selected by the high and low cutoff frequencies. 2.2 OPERATING PROCEDURE 2.2.1 Channel Selection Up and down controls and increase or decrease channel setting shown on the DISPLAY. When held, channels will cycle through all active channels continuously. Channel selection can also be accomplished by entering the desired channel number in the keyboard and momentarily pressing either up or down channel controls. 2.2.2 All Channel Key Procedure When frequency, input/output gain, type, mode or coupling are entered or changed, and the LED in the ALL CHAN key is on, the new setting will also be entered in all other filters of the same card type. 2.2.3 Cutoff Frequency Data entry keyboard controls 0 to 9 and . set the numeric value of the cutoff frequency desired. To program 1.5kHz press the 1.5 data keys and parameter keys KILO and FREQ. The cutoff frequency will be entered only in the channel displayed and indicated in Hertz in the four digit DISPLAY. Model 34A Plug-In Filter Card 8 2.2.4 Input Gain (Pre-Filter) Up and down GAIN SET controls and increase or decrease the input amplifier by 20dB. The two digit DISPLAY will indicate either 00 or 20dB. 2.2.5 Output Gain (Post-Filter) Up and down GAI SET controls and increase or decrease the output amplifier by 20dB. The two digit DISPLAY will indicate either 00 or 20dB. 2.2.6 Mode of Operation When the MODE key is pressed, the DISPLAY indicates the mode of operation in the channel displayed, alternating as the MODE key is pressed between low-pass “L.P.”, high-pass “h.P.”, band-pass “b.P.”, band-reject “b.r.” and by-pass “bYP.” which connect input to output. 2.2.7 Filter Type The DISPLAY will indicate the filter type in the channel displayed when the TYPE key is pressed, alternating between Butterworth “bu.” and Bessel “bES.” response. 2.2.8 Input Coupling Pressing the SECONF FUNCTN key followed by the TYPE key will display the input coupling, indicating “AC” or “dC”, and will alternate when the two key are pressed again only when in the low-pas and band-reject mode. High-pass and band-pass mode are AC only. 2.2.9 Clear Entry Key Operation When entering a numeric value in the keyboard, but not specifying a parameter, pressing the clear entry key will function as an error correction procedure and restore DISPLAY to its previous set-up. When a numeric value and its parameter has been entered and the numeric value is then changed, pressing the CE key will restore DISPLAY to the previous value of that parameter. When either the SECOND FUNCTNSTORE or RECALL key is pressed, the next memory location will be indicated on the DISPLAY. Pressing the CE key will restore DISPLAY to its previous setting. When the DISPLAY contains information other than the frequency, pressing the CE key will restore the DISPLAY to the current frequency. If the Model 3905B or 3916B is operating via the IEEE-488 bus (the front panel REMOTE LED is on), pressing the CE key will return unit to LOCAL operation. Model 34A Plug-In Filter Card 9 2.2.10 Storing Set-Ups If a memory location is entered into the keyboard, pressing the SECOND FUNCTNSTORE key will store the entire five card (Model 3905B) or sixteen card (Model 3916B) set-ups into the memory location selected. The maximum number of memory locatio