Fender Bassman 1200 User manual

BASSMAN 1200
(This is the model name for warranty claims)
P/n 021-3300-010 (120V)
SERVICE MANUAL
CONTENTS:
Notices
Specifications
Circuit description
Parts lists:
PCB assembly
Chassis assembly
End item
Footswitch assembly
Footswitch PCB
Schematics
Service diagrams
Fender Musical Instruments Corp. 8860 East Chaparral Road Suite 100 Scottsdale, AZ 85250

BASSMAN 1200
(This is the model name for warranty claims)
SERVICE MANUAL
AUGUST 1998
IMPORTANT NOTICE:
The information contained herein is CONFIDENTIAL and PROPRIETARY to Fender Musical Instruments Corp. It is
disclosed solely for use by qualified technicians for purposes of equipment maintenance and service. It is not to be
disclosed to others without the expressed permission of Fender Musical Instruments Co. All specifications subject to
change without notice.
For warranty repair service, only Fender specified part numbers are to be used. It is recommended they also be used
for post-warranty maintenance and repair.
Parts marked with an asterisk (*) indicate the required use of that specific part. This is necessary for RELIABILITY and
SAFETY requirements. DO NOT USE A SUBSTITUTE!
A coded naming convention is used in the description of certain parts. The codes and what they mean are as follows:
CAPACITOR CODES HARDWARE CODES
CAP AE =Aluminum Electrolytic BLX =Black Oxide
CAP CA =Ceramic Axial CR =Chrome Plated
CAP CD =Ceramic Disk HWH =Hex Washer Head
CAP MPF =Metalized Polyester Film M=Machine Screw
CAP MY =Mylar NI =Nickel Plated
CAP PFF =Polyester Film/Foil OHP =Oval Head Phillips
PB =Particle Board
RESISTOR CODES PHP =Pan Head Phillips
PHPS =Pan Head Phillips Sems
RES CC =Carbon Comp SMA =Sheet Metal "A" Point
RES CF =Carbon Film SMB =Sheet Metal "B" Point
RES FP =Flame Proof SS =Stainless Steel
RES MF =Metal Film TF =Thread Forming
RES WW =Wire Wound ZI =Zinc Plated

BASSMAN 1200
(This is the model name for warranty claims)
SPECIFICATIONS
Product Release No.: PR 513 (This is not a model number)
Part Number: 120V Version : 21-330010
240V Aus : 21-333010
230V UK : 21-334010
230V : 21-336010
100V JPN : 21-337010
110V TW : 21-331010
220V ROK : 21-339010
Preamp section
Input impedance: 470k Ω
Full power sensitivity: 12.75mV
Tone controls: Treble: +/- 15dB @ 3kHz
Bass: +/- 15dB @ 40Hz
Graphic Equalizer: +/- 12dB @ 31.5Hz, 63Hz, 125Hz, 250Hz, 500Hz, 1kHz, 2kHz,
4kHz, 8kHz, 16kHz
Mid notch: -20dB @ 700Hz
Low boost: +10dB @ 40Hz
High boost: +10dB @ 6kHz
Power Amplifier Section
Power output: 1200 Watts RMS into 2 Ω@ <0.2% THD
Sensitivity: 1V RMS (0dBV)
Power Requirements: 100V AC, 50/60 Hz, 1800W
120V AC, 60 Hz, 1800W
230V AC, 50 Hz, 1800W
Speaker Complement: Designed for use with the Bassman 410 or Bassman 215 Bass
Loudspeaker Enclosures
Dimensions: Height: 3.5" (8.9 cm)
Width: 19.0" (48.3 cm)
Depth: 15.0" (38.1 cm)
Weight: 35 lbs (15.9 kg
Product specifications are subject to change without notice

BASSMAN 1200
(This is the model name for warranty claims)
CIRCUIT DESCRIPTION
The Bassman 1200 Bass Amplifier employs many new technologies in various sections. This document is a
brief overview.
Preamp
The preamp section employs two 12AX7 tubes. Channel one (V1) is fairly conventional, while channel two (V2) uses a
second tube with additional op-amp gain (U2B) to provide a 60's style overdrive sound. The op-amp is used as
straight gain and is never allowed to become non-linear.
In typical operation, the drive channel and the clean channel are presented to the channel 1/2 mix control (R25) so that
a "blend" can be established. The channel select button (S7) on the front panel (or it's foot switch counterpart) selects
between this channel mix or channel one only. This selection employs JFETS Q1-Q4.
Signals are then presented to a second-order Sallen and Key filter set to F0 of 36.6 Hz and a Q of 2.1. This filter
provides about 6.5dB of boost at 41 Hz.
The signal path is routed to U4B where low-boost (S2) , mid-notch (S4), and high-boost (S3) equalization switches can
be used. These circuits are followed by conventional Baxendall low (R67) and high (R70) equalization. The Baxendall
circuit output is then sent to a graphic equalizer which can be selected by the footswitch or graphic EQ button (S61) on
the front panel. The far-right graphic EQ slider (R660) is a +/- 10dB trim for graphic EQ gain compensation.
Next, the signal is presented to a second-order state-variable filter before being presented to the compressor circuit.
Said filter is set to 420 Hz. At the compressor, low-frequency compression ratio (R88) and high-frequency
compression ratio (R98) are adjustable to suit the user. Audio is presented to the "compressor EQ balance" (R107).
The compressor EQ balance controls the mix ratios of the compressor outputs. A compressor gain trim (R113) is
provided to compensate for the amount of amplification lost due to using the compressor. The compressor-gain trim
control is able to compensate for a compressed signal of up to 10dB.
The FETs Q5 and Q6 select between pre- and post-compressor via the front panel switch (S8) or footswitch. After
passing through op-amp U10B and master-gain control R116, the signal is sent to output jack J3, effects-loop send.
The signal input at J4, effects-loop return, goes to differential receiver U11B.
Signals are forwarded to power amp pass through amplifier U12B and on to J5. At these same nodes, the signal is
passed on to the 1200 Watt class H power amplifier.

BASSMAN 1200
(This is the model name for warranty claims)
Power Amplifier
The power amplifier employs class AB topology in the pre-driver circuit Q8-Q11. Quiescent current is established with
transistors Q12-Q13. Driver transistors Q16-Q17 provide drive for Q23-Q26, and Q31-Q34. Transistors Q19,Q21, and
Q27-Q30 provide positive “on demand” supply-rail boost. Transistors Q20, Q22, and Q35-Q38 provide the same
function for the negative rail.
Transistor Q18 provides “charge depletion” of Q23-Q26 and Q31-Q34. This allows for the suppression of common
mode current that can occur at high frequencies.
Relay K1 and associated components reduce output-stage current gain to unity during power-up and over-temperature
events as monitored by thermistor RT1 on the main heatsink.
Power supply
Primary circuit inrush limiting is accomplished by TH1, a negative temperature coefficient thermistor.
The power supply employs a toroidal power transformer with only one tapped-main secondary. Two large bridge
rectifiers are used to obtain +/-47VDC and +/- 94VDC.
High voltage (356VDC) for vacuum tube sections is generated by half-wave multiplier comprised of CR92-CR95,
C125-C128.
Low voltage (+/-22VDC) and (+10~ +28VDC variable fan) is supplied by the synchronous rectifier system located on
the power supply break-away board. This synchronous system observes the input sine and allows Q81, Q85, and Q88
to be forced on until the input sine wave reaches the correct level as observed by Q83, Q87, and Q90. References
Q84 (variably controlled by RT2) CR811 and CR818 are employed. Regulators U21 and U22 reduce the +/-22V lines
to +/-16VDC
Heater voltage (24VDC for 2 series-connected 12AX7s in the preamp) is derived from the 32VDC supply (+/-
16VDC).. Excess voltage is dropped across across paralleled ballast resistors, R354-R356, on the preamp PCB.

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY
QTY PART # DESCRIPTION REFERENCE DESIGNATION
20052047000 BRIDGE RECT 35A 800V BR1 BR2
90048451000 BUTTON PUSH OFF WHITE
20053930000 CABLE RIBBON 3 CKT 3 in P1A P5A
10048914000 CABLE RIBBON 8 CKT 7 in P4A
10054388000 CABLE RIBBON 8 CKT 9 in P8A
20033606003 CAP AE RDL .47UF 50V 20% C116 C640
30028494000 CAP AE RDL 1000uF 35V 20% C802 C805 C809
20028476003 CAP AE RDL 100UF 50V 20% C806 C810
60028463003 CAP AE RDL 10UF 50V 20% C39 C43 C46 C50 C55 C59
10028458003 CAP AE RDL 1UF 50V 20% C53
10 0028459003 CAP AE RDL 2.2UF 50V 20% C24 C34-35 C52 C57 C81-83 C85 C88
20054204000 CAP AE RDL 22UF 450V 20% C130-131
37 0028467003 CAP AE RDL 22UF 50V 20% C1-2 C7 C19 C23 C40 C48 C51 C56
C61 C64-66 C69 C72-74 C76 C105
C134 C137 C601 C603-613 C634 C636
C638-639
40028460003 CAP AE RDL 4.7UF 50V 20% C12-13 C28 C161
20053955003 CAP AE RDL 47UF 160V 20% C92-93
40054206000 CAP AE RDL 47UF 350V 20% C125-128
10054205000 CAP AE RDL 47UF 450V 20% C129
60047195003 CAP AE RDL 47UF 63V 20% C4 C86 C98-99 C803 C807
20037182000 CAP AE RDL 6800UF 63V 20% C121-122
20053915000 CAP AE100V10000uF 20% C123-124
10039261001 CAP CA 330PF 100V C80
34 0034788003 CAP CD .1UF 50V 20% .15"CUT C644-649 C94-95 C132-133 C135-136
C139-160
30051457003 CAP CD 100pF 500V 5% C100-101 C637
20051960003 CAP CD 180 PF 500V 10% C14 C20
90051406003 CAP CD 220PF 500V 10% C25 C45 C62-63 C67-68 C70-71 C641
40051445003 CAP CD 22PF 500V 5% C18 C49 C54 C58
30051409003 CAP CD 68pF 500V 5% C16 C60 C89
20027255003 CAP MPF .001UF 100V C5 C11
30027257003 CAP MPF .0022UF 100V C44 C47 C87
10027260003 CAP MPF .0039UF 100V C79
50027261003 CAP MPF .0047UF 100V C38 C84 C96-97 C162
20027262003 CAP MPF .0068UF 100V C41-42
20027264003 CAP MPF .01UF 100V C602 C635

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
10047165000 CAP MPF .01UF 250V C138
90027267003 CAP MPF .022UF 100V C31-33 C622-627
90027272003 CAP MPF .047UF 63V C26-27 C75 C107-108 C114-115 C642-
643
10027275003 CAP MPF .068UF 100V C30
10027277003 CAP MPF .082UF 100V C17
60027280003 CAP MPF .15UF 63V C616-C621
14 0027278003 CAP MPF .1UF 63V 10% C3 C6 C10 C29 C36-37 C106 C109-111
C113 C801 C804 C808
10027281003 CAP MPF .22UF 63V C112
40027283003 CAP MPF .33UF 63V C77-78 C614-615
10027286003 CAP MPF .47UF 63V C117
30024853000 CAP MPF RDL .1UF 250V 10% C118-120
50024854000 CAP MPF RDL .1UF 400V 10% C8 C9 C15 C21 C104
10024823000 CAP MPF RDL.01uf 400v 10% C22
60030937003 CAP PFF RDL .0027UF 50V 5% C628-633
11 0050514000 CONTROL SLIDER 30MM 50KW R607-616 R660
30027945000 CONTROL SNAPIN 100K B TAPER R113 R88 R98
10053926000 CONTROL SNAPIN 10K 5A 10K 5C R107
10053929000 CONTROL SNAPIN 10K B 250K B R25
20039053000 CONTROL SNAPIN 1M 30A R20 R47
10053928000 CONTROL SNAPIN 250K 30A TAPER R37
20031087000 CONTROL SNAPIN 25K 2B W/DETENT R67 R70
10027941000 CONTROL SNAPIN 50K B TAPER R116
15 0064089001 DIODE 1N4003 LL CR44-45 CR103-104 CR801-802
CR805-808 CR812-815 CR819
40026730001 DIODE 1n4006 800v LL CR92-95
72 0006260001 DIODE 1N4448 SIGNAL LL CR3-27 CR38-39 CR50-53 CR60 CR62-
85 CR87-88 CR96-100 CR601-603
CR803-804 CR809-810 CR816-817
40054209001 DIODE 1N5817 1A CR36-37 CR42-43
20029045000 DIODE 6A 400V 6A4 LEAD FORMED CR58-59
12 0025821001 DIODE HV FDH-400 SWITCHING LL CR28-35 CR46-47 CR54-55
20052050000 DIODE MUR1520 200PRV 15AMP CR56-57
10041261000 DIODE VOLT REF LM4040DIZ-10.0 U15
20009165001 DIODE ZEN 1n4744a 15v 1w 5% CR90-91
10027329001 DIODE ZEN 1n5228b 3.9v 5% LL CR86
40027327001 DIODE ZEN 1n5234b 6.2v 5% LL CR40-41 CR101-102
10029898001 DIODE ZEN 1N5236B 7.5V 5% CR89
50031635001 DIODE ZEN 1n5240b 10v 5% LL CR1-2 CR48-49 CR61
20038686001 DIODE ZEN IN4737A 7.5V.5W 5% CR811 CR818

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
11 0025802000 FSTN TAB MALE .250 x .032 PCB MT CP1-11
20025996000 FUSE CLIP PCB .250 5MM FUSE XF1
10053654000 GASKET HEATSINK 1200S
10027408000 HDR .1 CTR 2 CKT SQ PIN P9
20027410000 HDR .1 CTR 3 CKT SQ PIN P1 P5
20027416000 HDR .1 CTR 8 CKT SQ PIN P4 P8
10053864000 HEATSINK DRVR 1200S FRNT
10053865000 HEATSINK DRVR 1200S REAR
10053488000 HEATSINK MAIN SUNN 1200S
10053866000 HEATSINK RECTIFIER 1200S
20025796000 HEATSINK TO-220
17 0051198000 IC DUAL OP AMP BA4560N SIP U5-7 U11-13 U16-17 U19-20 U61-67
70016795000 IC DUAL OP AMP TL072 U1-4 U9-10 U14
10051680000 IC DYNAMIC RANGE PROCESSOR DUAL
VCA SSM2120 U8
10013562000 IC REGULATOR 15V MC7815CT U21
10013564000 IC REGULATOR 15V MC7915CT U22
10051856000 IC QUAD 2-IN NAND GATE 4011 U18
10027387000 INDUCTOR AIR CORE RDL 2.5UH L1
40017974000 INSULATOR MICA TO-220
20 0038815000 INSULATOR SILICONE TO-3P
10051006000 JACK 1/4 PCB DUAL TIP MONO J1
20051658000 JACK MONO R/A J2 J12
40029175000 JACK PHONE 1/4" HI CURRENT PC J8-11
40053450000 JACK STEREO RA J3-6
10049892000 JACK XLR MALE J7
40028039000 LED RED 5x5MM SLB-55VR3 LD3-5 LD61
20053951000 LED RED, T-1.75 Clr LD1-2
10033177000 LED RED/GREEN 5x5mm BI-COLOR LD6
10053616000 PCB MAIN SUNN 1200S
10036613000 RELAY DPDT DIP 24 VOLT 8.3mA K1
20026505001 RES CF 1/2W 5% 1 OHM LL R813 R819
30026368001 RES CF 1/2W 5% 100 OHM R3-5
40025116001 RES CF 1/2W 5% 100K R18 R23 R36 R44
40026493001 RES CF 1/2W 5% 2.7K LL R238 R244 R268 R675
30026512001 RES CF 1/2W 5% 3.9K LL R802 R809 R815
20025941001 RES CF 1/2w 5% 560 ohm LL R6 R292
40024967001 RES CF 1/4W 5% 1.2K R13 R22 R31 R637

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
20028862001 RES CF 1/4W 5% 1.3K R159-160
70024969001 RES CF 1/4W 5% 1.5K R43 R58 R155-156 R179-180 R229
20025073001 RES CF 1/4W 5% 1.5M R86 R96
20024937001 RES CF 1/4W 5% 10 OHM R230 R301
20024952001 RES CF 1/4W 5% 100 OHM R119 R130
18 0024997001 RES CF 1/4W 5% 100K R12 R16 R33-34 R56 R122 R133 R135-
136 R140 R196-197 R228 R277-279
R282 R668
61 0024981001 RES CF 1/4W 5% 10K R8 R10 R14 R24 R26 R28-29 R32 R38
R48 R50-51 R54 R60 R69 R72-74 R77
R79 R82-83 R89 R99 R106 R110 R115
R117-118 R120-121 R124-129 R131-
132 R137 R141 R157-158 R236 R241
R253 R265 R276 R285 R290 R601-606
R657-658 R664-665 R671
10024998001 RES CF 1/4W 5% 120K R21
30024983001 RES CF 1/4W 5% 12K R143 R188-189
20029539001 RES CF 1/4W 5% 13K R61-62
50024999001 RES CF 1/4W 5% 150K R41 R95 R251 R256 R271
40024985001 RES CF 1/4W 5% 15K R642 R647 R651 R656
20024986001 RES CF 1/4W 5% 18K R633 R638
11 0024965001 RES CF 1/4W 5% 1K R17 R93 R103 R151 R153 R646 R655
R803-804 R811 R817
18 0025069001 RES CF 1/4W 5% 1M R9 R15 R27 R30 R39 R59 R64 R94
R104 R139 R240 R246 R270 R274
R302-303 R670 R673
60024971001 RES CF 1/4W 5% 2.2K R235 R248 R257 R652 R810 R816
10025075001 RES CF 1/4W 5% 2.2M R289
50029455001 RES CF 1/4W 5% 2.4K R87 R97 R198-199 R634
10024942001 RES CF 1/4w 5% 22 ohm LL R806
60024956001 RES CF 1/4W 5% 220 OHM R90-91 R100-101 R123 R134
10025059001 RES CF 1/4W 5% 220K R19
18 0024987001 RES CF 1/4W 5% 22K R46 R52 R227 R242-243 R252 R261
R263-264 R266-267 R272 R286 R288
R661-662 R672 R674
20024988001 RES CF 1/4W 5% 27K R144-145
10029005001 RES CF 1/4W 5% 2K R643
70024973001 RES CF 1/4W 5% 3.3K R40 R617-618 R620 R622-623 R625
20026504001 RES CF 1/4W 5% 3.6K R65-66
40024975001 RES CF 1/4W 5% 3.9K R192-193 R628 R640
40028865001 RES CF 1/4W 5% 30K R639 R644 R648 R653
30025061001 RES CF 1/4W 5% 330K R49 R262 R275
30024989001 RES CF 1/4W 5% 33K R627 R630 R635
10024960001 RES CF 1/4w 5% 390 ohm R807
10025063001 RES CF 1/4W 5% 390K R53

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
70024991001 RES CF 1/4W 5% 39K R68 R80 R84 R105 R109 R186-187
40029610001 RES CF 1/4W 5% 3K R619 R621 R624 R626
10029472001 RES CF 1/4W 5% 4.3K R649
50024977001 RES CF 1/4W 5% 4.7K R55 R57 R142 R176 R631
10025079001 RES CF 1/4w 5% 4.7m LL R284
10029592001 RES CF 1/4w 5% 43 ohm LL R184
20029451001 RES CF 1/4w 5% 430 ohm LL R174-175
50024947001 RES CF 1/4W 5% 47 OHM R81 R85 R146 R194-195
90024961001 RES CF 1/4W 5% 470 OHM R1-R2 R204-207 R280 R287 R293
50025065001 RES CF 1/4W 5% 470K R7 R45 R233 R247 R669
14 0024993001 RES CF 1/4W 5% 47K R42 R71 R108 R111-112 R114 R147-
150 R152 R154 R163 R281
10028034001 RES CF 1/4W 5% 5.1K R291
50024978001 RES CF 1/4W 5% 5.6K R11 R35 R76 R659 R663
20025066001 RES CF 1/4w 5% 560k LL R258-259
40024994001 RES CF 1/4W 5% 56K R75 R78 R641 R650
10028948001 RES CF 1/4W 5% 6.2K R63
30024979001 RES CF 1/4W 5% 6.8K R237 R666-667
10029596001 RES CF 1/4W 5% 62 OHM R185
70024995001 RES CF 1/4W 5% 68K R92 R102 R138 R181 R234 R629 R632
20025942001 RES CF 1/4W 5% 7.5K R645 R654
10028153001 RES CF 1/4W 5% 75K R283
20029581001 RES CF 1/4W 5% 8.2 OHM R170-171
10024980001 RES CF 1/4W 5% 8.2K R636
20024964001 RES CF 1/4w 5% 820 ohm LL R172-173
40025068001 RES CF 1/4W 5% 820K R239 R245 R269 R273
10029613001 RES CF 1/4w 5% 91k LL R260
10027627001 RES FILM 1W 5% 10 OHM R224
20027348001 RES FILM 1W 5% 3.3K R202-203
10053946001 RES FILM 2W 5% 180K R297
30036921001 RES FILM 2W 5% 1k R805 R812 R818
20027628001 RES FILM 2W 5% 47 OHM R225-226
10041810001 RES FILM 2W 5% 6.8K R298
20036960001 RES FUSE MF 1/4w 5% 47ohm T/R R200-201
20015582001 RES MF 1/4w 1% 10k LL R250 R254
10016965001 RES MF 1/4w 1% 12.1k R249
10027632001 RES MF 1/4w 1% 2.43k LL R231
10036379001 RES MF 1/4w 1% 23.7k LL R255
10016961001 RES MF 1/4w 1% 6.81k LL R232
50051731001 RES MF FUSE 1/4W 5% 1K ohm T/R R161-162 R182-183 R304

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
20041738001 RES MOX 1W 15k 5% LL R190-191
10028022001 RES MOX 2W 120 OHM 5% R294
20031008001 RES MOX 2W 240 ohm 5% R295-296
20036470001 RES MOX FP 1W 5% 10K R299-300
20041741001 RES MOX FP1/2W 5% 47 ohm R164-165
80050815001 RES WW 3W 5% .05 OHM LL R220-223 R212-215
80050814000 RES WW BT 5W 10% .15 OHM R216-219 R208-211
20053921000 RES WW 5W 1.3kohm10 R168-169
30054207000 RES WW 5W 2.2ohm 10 R801 R808 R814
20053922000 RES WW 10W 470ohm10 R166-167
20 0032934000 SCRW TF 4-40x1/2 HIHS ZI @ Q16-17 Q21-38
17 0027638000 SCRW TF 4-40x3/8 HWHS ZI .1"HD @ U21-22 Q10-11 Q13 Q19-20 CR56-
57 PLUS 8 @ HEATSINK
20028500000 SCRW TF 8-32x3/4 HWH SLTD Z1
10051411000 SPACER LED .4X.1 TURQUOISE @ LD61
40036178000 SPACER LED .5x.1 BRN @ LD3-5 LD6
10050817000 SWITCH PB PC VERT MNT DPDT S61
80028091000 SWITCH PUSH SLFLK SHORT STROKE S1-8
10053923003 THERMAL SENSOR PTC 80 DEG C RT2
10052051000 THERMISTOR, NTC 20 TH1
10051418003 THERMISTOR, PTC100 DEG C RT1
20029167000 TUBE SOCKET 9 PIN PCB MOUNT
20 0032937000 WSHR CONE
40017746000 WSHR SHLDR NYL 1/8x1/4
10027325000 XFMR LINE OUTPUT T1
10 0054418000 XISTOR NPN 2SC3263 Q16 Q21 Q23-30
10 0054417000 XISTOR PNP 2SA1294 Q17 Q22 Q31-38
10 0041465003 XSTR N-CH JFET J113 TO-92 Q1-7 Q46 Q61-62
10016739003 XSTR NPN 2N4401 TO-92 Q45
10025751003 XSTR NPN 2SC2362K/2SC2389STPS Q8
30028760000 XSTR NPN 2SC4793/2SC3298B Q11 Q18-19
40051448003 XSTR NPN 2SD1857 Q12 Q14 Q82 Q86
10028164000 XSTR NPN MJE15030 Q88
20014867003 XSTR NPN MPSW42 (TO-92) Q83 Q87
70016742003 XSTR PNP 2N4403 TO-92 Q39 Q41-44 Q63 Q84

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
20025752003 XSTR PNP 2SA1038STPS Q9 Q40
30028759000 XSTR PNP 2SA1837 TOP-220 Q10 Q13 Q20
20051447003 XSTR PNP 2SB1236 Q15 Q89
20028166000 XSTR PNP MJE15031 Q81 Q85
10014866003 XSTR PNP MPSW92 TO-226AE Q90
CHASSIS ASSEMBLY
QTY PART # DESCRIPTION REFERENCE DESIGNATION
1025905 BUSHING SR .875x.125x3/4 7-K-2 230V/240V UNITS
1025907 BUSHING SR .875x.125x3/4 7-W-2 120V/100V UNITS
1040994 CABLE ASSY PWR 10A U.K..250TAB 230V UK
1048912 CABLE ASSY PWR 14GA 120V .250 120V
1026622 CABLE ASSY PWR 14GA 230V .250 230V
1038602 CABLE ASSY PWR AUST .250 TAB 240V AUST
1057488 CHASSIS TOP BASSMAN 1200
1057487 CHASSIS BASSMAN 1200
1053911 COOLING FAN, DC 24V
2049650 CORD WRAP STYLE 2
1020802 FUSE QA 20mmx5mm 250v 10A 230V/240V VERSIONS
1032030 FUSE TD 1-1/4x1/4 250v 20A 120V/100V VERSIONS
11 053986 KNOB ROTARY SS W/CHR INSERT
1057489 LEXAN INSERT BASSMAN 1200
1069393 NUT 6-32 HEX EXT LOCK GND SCREW
5016352 NUT HEX 3/8-32x3/32 TK NI AT 1/4" JACKS
1028272 NUT KEP 1/4x20 FOJ FOR XFORMER
4022004 NUT KEPS #8-32 ZINC FAN MOUNT
1053912 PCB ASSY SUNN 1200S
2051652 RACK EAR SUNN 1200S
1053910 SCREW M 1/4-20 x 3" CAR BLX FOR XFORMER
2037623 SCREW TC25 6 x 1/2" PHP ZI @CORD WRAPS
6026501 SCRW C 1/4-20x1/2 HH BLK RACK EARS TO CHASSIS

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
CHASSIS ASSEMBLY (CONT)
QTY PART # DESCRIPTION REFERENCE DESIGNATION
4 033051 SCRW M 6-32x1/2 PHP ZI LW MAIN HS TO STDOFFS
4033051 SCRW M 6-32x1/2 PHP ZI LW H.S. TO STDOFF
10 014999 SCRW M 6-32x1/4 PHP BLX EQ PCB AND PCB STDOFF
19904101500 SCRW M 6-32x3/8 PHPS BLX ITLW GND SCREW
4069385 SCRW M 6-32x5/8 PHP ZI EQ PCB to STDOFF
4029656 SCRW M 8-32x3/8 PHP BLX SEM/LW FAN MOUNT
10 031184 SCRW M6-32x1/4 PHPS BLX ITLW MAIN PCB TO CHASSIS
2051155 SCRW SMB #4X3/8 PHP BLX @ XLR jack
19 028684 SCRW SMB 6x3/8 PH PHS BLX @ CHASSIS PANELS
10 031073 STANDOFF 6-32x3/8 RND AL MAIN PCB TO CHASSIS
4053931 STANDOFF 6-32x9/16 RND AL
4037783 STANDOFF NYL PCB SNAP 1/4" NAT EQ SANDWICH
4053952 STANDOFF, NYLON BLACK .250"
040582 SWITCH DPST .250 TAB GLOBAL EXPORT
1039236 SWITCH ROCKER DPST PSEUDO-IEC DOMESTIC
2013341 TUBE 7025/12AX7WA RUSSIAN MADE 12AX7A
19904300900 WASHER FLAT 1/4X1 STL BLX FOR XFORMER
4027520 WSHR FLAT .380x.630 FIBER AT SPEAKER JACKS
5031153 WSHR FLAT 3/8x.614 NI AT 1/4" JACKS
1016436 WSHR LCK INTL 3/8x.687x.035 NI AT 1/4" INPUT JACK
4026401 WSHR SHLDR FIBER 3/8x5/8 AT SPEAKER JACKS
6022285 WSHR SP LOCK 1/4x.493 ZI RACK EARS TO CHASSIS
1053909 XFRMR POWER TOROIDAL 100V 1200H 100V
1053908 XFRMR POWER TOROIDAL 230V 1200H 230V/240V
1050855 XFRMR POWER TOROIDAL DOMESTIC
1200H 120V
END ITEM
QTY PART # DESCRIPTION REFERENCE DESIGNATION
1057748 CHASSIS ASSY BASSMAN 1200 120V
1057751 CHASSIS ASSY BASSMAN 1200 240V AUST
1057750 CHASSIS ASSY BASSMAN 1200 230V UK
1057749 CHASSIS ASSY BASSMAN 1200 230V
1057747 CHASSIS ASSY BASSMAN 1200 100V
1057752 CHASSIS ASSY BASSMAN 1200 220V ROK
1 057745 FOOTSWITCH 3 BUTTON BASSMAN

BASSMAN 1200
(This is the model name for warranty claims)
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
FOOTSWITCH END ITEM
QTY PART # DESCRIPTION REFERENCE DESIGNATION
1053897 PCB ASSY FTSW 3 BTN SUNN BASS
1057746 PLATE TOP FOOTSWITCH ASSY 3 BTN BASS
1028895 CABLE ASSY FTSW RT ANG 12'
1028109 HSG END CUP LEFT FTSW
1028143 HSG END CUP RIGHT FTSW
1028141 HSG FTSW 3 BUTTON
1031647 NUT HEX 12mmx1mm Nl
8028684 SCRW SMB 6x3/8 PH PHS BLX
3031899 WSHR NYL .485x.775x.150 TK
FOOTSWITCH PCB ASSEMBLY
QTY PART # DESCRIPTION REFERENCE DESIGNATION
1053898 PCB FAB FTSW 3 BTN SUNN BASS
2000626 DIODE 1N4448 SIGNAL LL
1031017 DIODE ZEN 1N5223B 2.7V 5%
2027327 DIODE ZEN 1N5234B 6.2V
3028039 LED RED 5x5MM SLB-55VR3
1037036 JACK PHONE PCB MONO CA PREMIUM
3041527 SPACER RND NYL .680x.250x.147
3028714 SWITCH PUSH SPDT