Page 2 - CAUTION
Micro-Tech 2400 Amplifier Service Manual 2 À PRÉVENIR LE CHOC ÉLECTRIQUE N’ENLEVEZ PAS LES COUVERTURES. RIEN DES PARTIES UTILES À L’INTÉRIEUR. DÉBRANCHER LA BORNE AVANT D’OUVRIR LA MODULE EN ARRIÈRE. TO PREVENT ELECTRIC SHOCK DO NOT REMOVE TOP OR BOTTOM COVERS. NO USER SERVICEABLEPARTS INSIDE. REFER...
Page 3 - Table of Contents
Micro-Tech 2400 Amplifier Service Manual 3 Introduction ............................................................. 4Scope ...................................................................... 4Warranty .................................................................. 4Parts Information ...........
Page 4 - Crown; SCOPE; Introduction
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 This manual con...
Page 5 - Parts Information
Micro-Tech 2400 Amplifier Service Manual 5 Parts Information shipment on a C.O.D. or pre-payment (check or creditcard) basis. TERMS Normal terms are pre-paid. Net-30 Days applies toonly those firms having pre-established accounts withCrown. If pre-paying, the order must be packed andweighed before a...
Page 6 - Specifications
Micro-Tech 2400 Amplifier Service Manual 6 Specifications Unless noted otherwise, all specifications are basedon driving an 8 ohm load per channel, both channelsdriven, the sensitivity switch in the 26dB position, theAC supply is 120VAC at 60Hz. Crown specificationsare guaranteed through the warrant...
Page 7 - Voltage Conversion; VOLTAGE SELECTION BOARD
Micro-Tech 2400 Amplifier Service Manual 7 Voltage Conversion The 120 Volt 60 Hz version, sold in the United States,is not voltage selectable. It does not have a voltageselection board. This version is to be used only with120 Volts and only with 60Hz. All other versions of the Micro Tech 2400 use a ...
Page 8 - Theory; OVERVIEW
Micro-Tech 2400 Amplifier Service Manual 8 Theory OVERVIEW It should be noted that over time Crown makes im-provements and changes to their products for variousreasons. This manual is up to date as of the time ofwriting. For additional information regarding theseamplifiers, refer to the applicable T...
Page 9 - VOLTAGE AMPLIFICATION; GROUNDED BRIDGE TOPOLOGY
Micro-Tech 2400 Amplifier Service Manual 9 Theory amplifies the difference between input and outputsignals, any difference in the two waveforms willproduce a near open loop gain condition which in turnresults in high peak output voltage. The output of theError Amp, called the Error Signal (ES) drive...
Page 11 - OUTPUT DEVICE EMULATION PROTECTION
Micro-Tech 2400 Amplifier Service Manual 11 respect to each other. This allows the power supply todeliver +Vcc and -Vcc from the same bridge rectifierand filter as a total difference in potential, regardlessof their voltages with respect to ground. The LS usesinverted feedback from the HS output to ...
Page 13 - Electrical Checkout Procedures
Micro-Tech 2400 Amplifier Service Manual 13 Electrical Checkout Procedures GENERAL INFORMATION The following test procedures are to be used to verifyoperation of this amplifier. DO NOT connect a load orinject a signal unless directed to do so by the proce-dure. These tests, though meant for verifica...
Page 14 - TEST 7: PHASE RESPONSE; TEST 12: OUTPUT POWER; In
Micro-Tech 2400 Amplifier Service Manual 14 TEST 6: VOLTAGE GAIN Spec 26dB Gain: Gain of 20.0 ±3%. Spec 0.775V Sensitivity: ±6%. Spec 1.4V Sensitivity: +12%/–6%. Initial Conditions: Controls per standard. Procedure: No load connected. Inject a 0.775 VAC 1 kHz sine wave with the Sensitivity Switch in...
Page 16 - SUPPLIMENTAL ITEMS
Micro-Tech 2400 Amplifier Service Manual 16 Parts List (Non-Module) SUPPLIMENTAL ITEMS CPN ITEM QTY D 4137-2 Nylon Thumbscrew Washer 4 C 3342-0 Feet, Black Self-Stick 4 A10087-71012 10-32 .75 Machine (Rack Screw) 4 K80603-2 MT Series Owners Manual 1 POWER SUPPLY CPN ITEM QTY D 7975-2 Power Cord (US ...
Page 17 - BACK PANEL ASSEMBLY
Micro-Tech 2400 Amplifier Service Manual 17 Parts List (Non-Module) OUTPUT ASSEMBLY CONT. (ONE PER CHANNEL) CPN ITEM QTY(PER CHANNEL) D 7665-9 Clip, TO-3P Mounting 2 D 7666-7 Bracket, TO-3P Heatsink 2 C 8813-5 Q318/Q418 Bias Servo MPSA18/MPS8097 1 B 5842-8 Tubing, #23 TFE Thin Wall Red (For C 8813-5...
Page 18 - MAIN CHASSIS ASSEMBLY; MISCELLANEOUS
Micro-Tech 2400 Amplifier Service Manual 18 Parts List (Non-Module) MAIN CHASSIS ASSEMBLY CPN ITEM QTY D 8501-5 Cover, Top 1 D 8548-6 Cover, Bottom 1 A10110-70605 Screw, 6-32-.312 Taptite Ph (Covers) 16 M21447J3 Main Chassis 1 MISCELLANEOUS CPN ITEM QTY A10110-70812 8-32 x .750 Taptite Pnhd Screw 2 ...
Page 19 - Module Information; MODULE HISTORY
Micro-Tech 2400 Amplifier Service Manual 19 Module Information MODULE HISTORY The Micro Tech 2400 amplifier was introduced inJanuary of 1995. Since then there have been severalupdates and revisions, some of which called for newmodules. The following is a list of all modules used upto this date, July...
Page 21 - CAPACITORS
Micro-Tech 2400 Amplifier Service Manual 21 Q43354-2 Output Module Parts List (P10429-2 Board) Q43354-2 Output Module for MT-2400. For Schematic See J0658-5 CAPACITORS C01 C 8511-5 .047µF C02 C 8426-6 .1µF C03 C 8426-6 .1µF C04 C 6806-1 .01µF C05 C 6806-1 .01µF C06 C 6806-1 .01µF C07 C 6807-9 .001µF...
Page 23 - RESISTOR NETWORKS
Micro-Tech 2400 Amplifier Service Manual 23 RESISTOR NETWORKS N101 N201 D 7944-8 Res. Net. N102 N202 D 6082-8 Res. Net. TRANSISTORS Q100 Q200 D 2961-7 2N3859A Q101 Q201 C 3578-9 MPSA93 Q102 Q202 C 3810-6 MPSA43 Q103 Q203 C 3786-8 PN4250 Q105 Q205 C 3578-9 MPSA93 Q106 Q206 C 3625-8 2N4125 Q107 Q207 C...
Page 24 - SWITCHES
Micro-Tech 2400 Amplifier Service Manual 24 R153 R253 A10124-24 JUMPER R154 R254 A10266-5601 56 R155 R255 A10266-1321 1.3K R156 R256 A10266-1321 1.3K R157 R257 A10266-1321 1.3K R158 R258 A10265-11321 11.3K R159 R259 A10265-10011 1K 1% R160 R260 A10266-5601 56 R161 R261 A10266-4701 47 R162 R262 A1026...
Page 26 - DIODES
Micro-Tech 2400 Amplifier Service Manual 26 Q43399-7 Main Module Parts List (D8827-4 Board) Q43399-7 MT-2400 MAIN MODULE Use Schematic J 0691-6 CAPACITORS C1 C 3913-8 470µF C2 C 3913-8 470µF C4 C 6802-0 .47µF C5 C 6806-1 .01µF C6 C 6806-1 .01µF C7 C 8897-8 .1µF C8 C 5362-6 2.2uF C100 C200 C 5311-3 2...