Marshall_marshall_18watt_schem 电路图 维修原理图.pdf

3 2 7 9 3 2 7 9 1 3 4 5 7 100K100K N O R M A L T R E M O L O 8.2K/2W280v300v1.5K-2K/2W 100K V1A V1B 1Meg1Meg 820 50F 25v 1 2 3 6 7 8 .005F .01F Tone 500K-A 470K .01F Volume 500K-A V2AV2B 1 2 3 6 7 8 100K 820 47K 470K .01F .01F .022F 8.2K 8.2K 100 3W 125/5W 50-500F/50v 470K 470K 16F/350v16-32F/450v32F/350v A 325v Standby (SPST) 15 (16) Ohm 0 (Gnd) 300v 300v 240v 220v 200v 1A SloBlow Fuse Power On/Off (SPST) 6.3v 6.3v Heater Filaments Power Lamp 6.3v A 470K 100K 220K .005F.005F 6 7 8 1 2 3 V3A V3B LO HI 1Meg 1Meg 68K 68K 50F 25v 820 External Foot Switch (SPST) 2.2Meg .01F.01F.01F 470K Tone 500K-A Volume 500K-A .005F 470pF V1 ECC83 V2 ECC83 V3 ECC83 V6 EZ81 V4 EL84 V5 EL84 1 3 45 7 3 45 2 7 9 ECC83/12AX7 Pinout 1 = Anode (2nd) 2 = Grid 1 (2nd) 3 = Cathode (2nd) 4 = Heater 5 = Heater 6 = Anode 7 = Grid 1 8 = Cathode 9 = Heater Tap 1 2 3 45 6 7 8 9 EL84/6BQ5 Pinout 1 = Internal Connection 2 = Grid 1 3 = Cathode 4 = Heater 5 = Heater 6 = Internal Connection 7 = Anode 8 = Internal Connection 9 = Grid 2 EZ81/6CA4 Pinout 1 = Anode 2 = No Connection 3 = Cathode 4 = Heater 5 = Heater 6 = No Connection 7 = Anode (2nd) 8 = No Connection 9 = No Connection .05F 2001 PedalMonkey Marshall 18 Watt Combo Schematic Components have been numbered for reference purposes only. All capacitors are rated for at least 400V unless otherwise noted. All resistors are rated Watt unless otherwise noted. V5 EL84 V4 EL84 V3 12AX7 V2 12AX7 V1 12AX7 4 5 4 545 9 45 9 45 9 From 6.3v Filament Heater Supply Filament Connections Note: Pins 4 and 5 of V6 (EZ81) Rectifier connect to a separate 6.3v filament supply as illustrated in the main schematic. Speaker Impedance Selector (SP3T) Power Selector (SP3T) 7 (8) Ohm 3 (4) Ohm Notes: Some 18Watt Marshall combos came equipped with 1Meg Volume and Tone Potentiomenters (R30, 31, 34, 35). Components with more than one value (R5, C2, C3) are the result of production variations. The differing values listed have been observed in authentic unmodified examples of this amplifier circuit. Experiment! Capacitor C4 has been intentionally omitted from the numbering scheme. S top looking. :) Intensity 1K-L Speed 2Meg-A This document is distributed for educational purposes ONLY. The components specified in this schematic utilize POTENTIALLY FATAL HIGH VOLTAGES. Maintenance and repair of all equipment utilizing hazardous voltages must be referred to a properly trained and qualified technician. PedalM expressly disclaim all liability for injury or property damage resulting from the misuse of any information contained in this document. 1. 2. 3. WARNING! This document and the illustrations contained herein are the property of PedalMonkey. Permission is not granted to make printed copies of this document or any portion thereof for the purpose of distribution. Further, electronic distribution of this document from any domain other than without the expressed permission of PedalMonkey is prohibited. The name Marshall is the property of Marshall Amplification. Revision 5 R3R4 R2 R7 R30 R1 R31 R9 R18R19 R13 R17 R23 R6 R15R16 R21 R22 R20 R25 R5 R27 R28 R8 R12 R11 R29 R14 R32 R10 R26 R24 R33 R34 R35 C11 C5 C16 C17 C18 C20-AC20-BC2 C15 C14 C8C9C10 C7 T2 T1 SW1 F1 SW2 J1 J2 J3 J4 C6 C3 C19 C1 C12 C13 SW3 SW4 SW5 I1 LO HI 收音机爱好者资料库 Ra d i o Fa n s .CN