Crown_Micro-Tech_2400_Service_Manual电路图.pdf

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1、Micro-Tech 2400 Amplifier Service Manual 1 MICRO-TECH -2400 POWER AMPLIFIER SERVICE MANUAL K-SVCMT24 7-95 Micro-Tech, ODEP and Crown are registered trademarks of Crown International, Inc. Mailing Address: P.O. Box 1000 Elkhart, IN U.S.A. 46515-1000 Shipping Address: 57620 C.R. 105 Elkhart, IN U.S.A.

2、 46517 1995 by CROWN INTERNATIONAL, INC. RadioFans.CN 收音机爱 好者资料库 Micro-Tech 2400 Amplifier Service Manual 2 PRVENIR LE CHOC LECTRIQUE NENLEVEZ PAS LES COUVERTURES. RIEN DES PARTIES UTILES LINTRIEUR. DBRANCHER LA BORNE AVANT DOUVRIR LA MODULE EN ARRIRE. TO PREVENT ELECTRIC SHOCK DO NOT REMOVE TOP OR

3、BOTTOM COVERS. NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL. DISCONNECT POWER CORD BEFORE REMOVING REAR INPUT MODULE TO ACCESS GAIN SWITCH. CAUTIONAVIS WARNING TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE! The information

4、furnished in this manual does not include all of the details of design, production, or variations of the equipment. Nor does it cover every possible situation which may arise during installation, operation or maintenance. If you need special assistance beyond the scope of this manual, please contact

5、 the Crown Technical Support Group. Mail: P.O. Box 1000 Elkhart IN 46515-1000 Shipping: 57620 C.R. 105 Elkhart IN 46517 Phone: (800) 342-6939/(219) 294-8200 FAX: (219) 294-8301 RadioFans.CN 收音机爱 好者资料库 Micro-Tech 2400 Amplifier Service Manual 3 Introduction .4 Scope.4 Warranty.4 Parts Information .5

6、Specifications.6 Voltage Conversion .7 Circuit Theory .8 Electrical Checkout Procedures.13 Parts List (Non-Module) .16 Module Information .19 M46330-3 Fuse Module .20 Q43327-8 Display Module .20 Q43354-2 Output Module .21 Q43328-6 Main Module.22 Q43399-7 Main Module.26 Table of Contents RadioFans.CN

7、 收音机爱 好者资料库 Micro-Tech 2400 Amplifier Service Manual 4 Crown Technical Support Group Factory Service Parts Department Mailing Address: PO Box 1000 Elkhart, IN USA 46515-1000 Shipping Address: 57620 C.R. 105 Elkhart, IN USA 46517 Phone: (219) 294-8200 Toll Free: (800) 342-6939 FAX: (219) 294-8301 Thi

8、s manual contains service information on Crown power amplifiers. It is designed to be used in conjunc- tion with the applicable Owners Manual. However, some important information is duplicated in this Ser- vice Manual in case the Owners Manual is not readily available. NOTE: THE INFORMATION IN THIS

9、MANUAL IS INTENDED FOR USE BY AN EXPERIENCED TECHNICIAN ONLY! SCOPE This Service Manual includes several sections. These sections include Parts Information, Specifications, Voltage Conversion, Circuit Theory, Electrical Test Procedures, Non-Module Parts Lists, and Module Parts Lists. Schematics are

10、attached. Note that com- ponent parts with circuit board comprise a complete module. Module part numbers are always associated with a specific circuit board, although an unpopulated circuit board may be built up with different parts to create different modules. Note that Crown does not sell blank (u

11、npopulated) circuit boards. Each of the compact audio power amplifiers are designed for professional or commercial use. Provid- ing high power amplification from 20Hz to 20KHz with minimum distortion, they feature balanced inputs with bridged and parallel monophonic capability. Specific features var

12、y depending on model family. WARRANTY Each Owners Manual contains basic policies as re- lated to the customer. In addition it should be stated that this service documentation is meant to be used only by properly trained service personnel. Because most Crown products carry a 3 Year Full Warranty (inc

13、luding round trip shipping within the United States), all warranty service should be referred to the Crown Factory or Authorized Warranty Service Center. See the applicable Owners Manual for warranty details. To find the location of the nearest Authorized Service Center or obtain instructions for re

14、ceiving Crown Fac- tory Service please contact the Crown Technical Sup- port Group (within North America) or your Crown/ Amcron Importer (outside North America). Introduction Micro-Tech 2400 Amplifier Service Manual 5 Parts Information shipment on a C.O.D. or pre-payment (check or credit card) basis

15、. TERMS Normal terms are pre-paid. Net-30 Days applies to only those firms having pre-established accounts with Crown. If pre-paying, the order must be packed and weighed before a total bill can be established, after which an amount due will be issued and shipment made upon receipt of pre-payment. N

16、ew parts re- turned for credit are subject to a 10% re-stocking fee, and authorization from the Crown Parts Department must be obtained before returning parts for credit. Crown is not a general parts warehouse. Parts sold by the Crown Parts Department are solely for servicing Crown/Amcron products.

17、Part prices and availabil- ity are subject to change without notice. GENERAL INFORMATION Later sections include both mechanical and electrical parts lists for this product. The parts listed are current as of the date printed. Crown reserves the right to modify and improve its products for the benefi

18、t of its customers. PART NUMBERING SYSTEMS As of the printing of this manual, Crown is using two numbering systems. The elder system always uses eight characters. The first character is a letter. Com- mon letters used are C, D, H, M, P, and Q. The second through sixth characters are numbers. The num

19、bers build sequentially (for each prefix letter) as new parts are added to our parts inventory system. (In some cases there will be a space then a four character number after the prefix letter; the space is considered a character.) The seventh character is usually a hy- phen, though it may be a lett

20、er to indicate a revision or special note. The last character is called a check-digit, and is useful to Crown for internal tracking. Crown is in the process of converting to a new part number system. Length may vary from eight to twelve characters. There is still a letter prefix, then five numbers.

21、These five numbers identify a type of part. The seventh character is a hyphen. Remaining char- acters identify the details of the type of part identified by the first part of the number. STANDARD AND SPECIAL PARTS Many smaller electrical and electronic parts used by Crown are stocked by and availabl

22、e from electronic supply houses. However, some electronic parts that appear to be standard are actually special. A part ordered from Crown will assure an acceptable re- placement. Structural items such as modules and panels are available from Crown only. ORDERING PARTS When ordering parts, be sure t

23、o give the product model, and include a description and part number (CPN/DPN) from the parts listing. Price quotes are available on request. SHIPMENT Shipment will be normally made by UPS or best other method unless you specify otherwise. Shipments are made to and from Elkhart, Indiana USA, only. Es

24、tab- lished accounts with Crown will receive shipment freight prepaid and will be billed. All others will receive Crown Parts Department Mailing Address: PO Box 1000 Elkhart, IN USA 46515-1000 Shipping Address: 57620 C.R. 105 Elkhart, IN USA 46517 Phone: (219) 294-8210 or: (219) 294-8211 Toll Free:

25、(800) 342-6939 FAX: (219) 294-8301 Micro-Tech 2400 Amplifier Service Manual 6 Specifications Unless noted otherwise, all specifications are based on driving an 8 ohm load per channel, both channels driven, the sensitivity switch in the 26dB position, the AC supply is 120VAC at 60Hz. Crown specificat

26、ions are guaranteed through the warranty period (normally 3 years). Because our testing methods are more strin- gent than our published specifications, every Crown amplifier will exceed its published specifications. POWER Power 8 Ohm Stereo520W/Ch 4 Ohm Stereo800W/Ch 2 Ohm Stereo1050W/Ch 8 Ohm Bridg

27、e Mono1585W 4 Ohm Bridge Mono2070W 2 Ohm Parallel Mono1530W 1 Ohm Parallel Mono2080W Load Impedances: Rated for 16, 8, 4, 2, and 1 (parallel mono only) Ohm operation; safe with all types of loads, even totally reactive loads. AC Mains: 120VAC at 60 Hz with standard three-wire grounded connector for

28、North American units; 100VAC, 120VAC, 220VAC, and 240VAC at 50 or 60 Hz when equipped with universal transformers, applicable fan assembly, and other applicable hardware with coun- try specific power cord. PERFORMANCE Frequency Response: 0.1dB from 20 Hz to 20 kHz at 1 Watt. Phase Response: 10 from

29、10 Hz to 20 kHz at 1 Watt. Signal to Noise Ratio: A-weighted, better than 105 dB below full rated output. Better than 100 dB below full rated output from 20 Hz to 20 kHz. Total Harmonic Distortion (THD): 0.05% from 20 Hz to 1 kHz, increasing linearly to 0.1% at 20 kHz at 500W. I.M. Distortion: 13V p

30、er microsecond. (Slew rates are limited to useful levels for ultrasonic/RF protection.) Damping Factor: 1000 from 10 Hz to 400 Hz. DC Offset: 10 millivolts. Input Impedance: Nominally 20K ohms balanced; 10K ohms unbalanced. Output Impedance: 10 milliohms in series with = 520W at 0.1% THD. Spec at 4

31、Ohm Stereo: = 800W at 0.1% THD. Spec at 2 Ohm Stereo: = 934W at 0.1% THD. International 8 Ohm Stereo: =515W at 0.1% THD. International 4 Ohm Stereo: =745W at 0.1% THD. International 2 Ohm Stereo: =925W at 0.1% THD. Initial Conditions: Controls per standard. Procedure: Load each channel to 8 ohms. In

32、ject a 1 kHz sine wave and measure at least 64.5 VAC at the output of each channel. Load each channel to 4 ohms. Inject a 1 kHz sine wave and measure at least 56.6 VAC. Load each channel to 2 ohms. Inject a 1 kHz sine wave and measure at least 43.2 VAC. All power measure- ments must be at less than

33、0.1% THD. TEST 13: REACTIVE LOADS Spec: No oscillations. Safe with all types of loads. Initial Conditions: Controls per standard. Procedure Capacitive: Load each channel to 8 ohms in parallel with 2 F. Inject a 20 kHz sine wave with 55 VAC output for 10 seconds. Procedure Inductive: Load each channe

34、l to 8 ohms in parallel with 159 Henries. Inject a 1 kHz sine wave with 35.8 VAC output for 10 seconds. Procedure Torture: Load each channel with the primary (red and black leads) of a DC-300A transformer (D 5781-6). Inject a 15 Hz sine wave at sufficient output level to cause 3 to 5 flyback pulses,

35、 for 10 seconds. Figure 4. Differentiator Circuit InOut .047 uF 1K Ohm Micro-Tech 2400 Amplifier Service Manual 15 Electrical Checkout Procedures Procedure Short: Inject a 60 Hz sine wave at 5 VAC minimum output. After establishing signal, short the output for 10 seconds. TEST 14: ODEP LIMITING Spec

36、: No oscillation on ODEP Limiting wave form; either channel controls limiting in Parallel Mono Mode. Initial Conditions: Controls per standard; rag or other obstruction blocking fan so that it does not turn. Procedure: Load the amplifier to 4 ohms on each channel. Inject a 60 Hz sine wave and adjust

37、 for 35 Vrms at the output. After a few minutes observe a wave form similar to Figure 5. Remove the input signal from both channels and allow the amplifier to cool for a few minutes. Switch the amplifier to Parallel Mono and remove the load from Channel 1. Inject the signal into Channel 1 and observ

38、e that ODEP limiting occurs at the output of both channels. Remove the load from Channel 2, and install the load on Channel 1. Again, observe that both channels limit. Return all amplifier controls to standard initial conditions. Remove the fan obstruction. TEST 15: LF PROTECTION Spec: Amplifier mut

39、es for low frequency. Initial Conditions: Controls per standard. Procedure: No load. Inject a 0.5 Hz 6 volt peak-to-peak square wave, or a 2 Hz 6VAC sine wave into each channel and verify that each channel cycles into mute. TEST 16: SIGNAL TO NOISE RATIO Spec: 100 dB below rated 8 ohm power 20 Hz to

40、 20 kHz. 105 dB A-Weighted. Initial Conditions: Controls per standard. Short inputs. Procedure: Load each channel to 8 ohms. Measure less than 645 V at the output of each channel (20 Hz- 20 kHz bandpass filter). TEST 17: TURN ON TRANSIENTS Spec: No dangerous transients. Initial Conditions: Controls

41、per standard. Procedure: From an off condition, turn on the amplifier and monitor the output noise at the time of turn on. Note: Turn on noise may increase significantly if the amplifier is cycled off and on. TEST 18: TURN OFF TRANSIENTS Spec: No dangerous transients. Initial Conditions: Controls pe

42、r standard. Procedure: From an on condition, turn off the amplifier and monitor the output noise at the time of turn off. Note: Turn off noise may increase significantly if the amplifier is cycled off and on. TEST 19: INTERMODULATION DISTORTION Spec at 0 dB Output: 0.01%. Spec at 35 dB Output: 0.05%

43、. Initial Conditions: Controls per standard. Procedure: Load each channel to 8 ohms. Inject a SMPTE standard IM signal (60 Hz and 7 kHz sine wave mixed at 4:1 ratio). Set the 60 Hz portion of the sine wave to 51.5 Volt RMS. Set the 7 kHz portion to 25%. With an IM analyzer measure less than 0.01% IM

44、D. Repeat test at 35 dB (reference 51.5 Volt RMS, 60 Hz portion) and measure less than 0.05% IMD. TEST 20: CLIPPING Spec: No protective action during test. Initial Conditions: Controls per standard. Procedure: Load each channel to 8 ohms. Inject a 1 kHz sine wave at each input and drive output 6 dB

45、into clip for 10 seconds. The amplifier should not activate any protective circuits (ODEP, Fault, or LF Protection). POST TESTING After completion of testing, if all tests are satisfactory, the amplifier controls should be returned to the posi- tions required by customer. If conditions are unknown o

46、r unspecified, factory settings are as follows: Level Controls: 9 to 11 OClock. Sensitivity Switch: 0.775V U.S., 1.4V International. Stereo/Mono Switch: Stereo. Ground Lift: Lift. Power: Off. Figure 5. ODEP Limiting Wave Form Micro-Tech 2400 Amplifier Service Manual 16 Parts List (Non-Module) SUPPLI

47、MENTAL ITEMS CPNITEMQTY D 4137-2Nylon Thumbscrew Washer4 C 3342-0Feet, Black Self-Stick4 A10087-7101210-32 .75 Machine (Rack Screw)4 K80603-2MT Series Owners Manual1 POWER SUPPLY CPNITEMQTY D 7975-2Power Cord (US Models)1 A10793-0503GPower Cord (European plug)1 D 8633-6Power Transformer (120V 60 Hz only)2 D 8631-0Power Transformer (Universal Volt)2 C 9508-0Circuit Breaker, 15A (100V-120V)2 C 8041-3Circuit Breaker, 7.5A (200V-240V)2 A10285-10Fuse, 1A 3AG (100V-120V)1 A1028