Fender Bassman 400 Service Manual - Service Notes
BASSMAN 400/400H
SERVICE NOTES
1.
CHASSIS REMOVAL is accomplished by first removing six (6) screws from the top, and one (1)
screw from each side of the cabinet; then slide the chassis out the rear.
2.
HEATSINK AIR BAFFLE should be in place before operating unit for extended periods. If baffle is
removed, take care not to pinch any wires when reinstalling. See Technote 2k-3 for additional
information.
The HF HORN is fuse-protected. This fuse is located on the rear speaker panel, near the Horn-
level control
PARTS LIST
NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY
PRINTED CIRCUIT BOARD ASSEMBLY - PREAMP
QTY PART # DESCRIPTION REFERENCE DESIGNATION
3
0029533000
CABLE JMPR 22GA 4 CKT 3.2”
PW1A-B PW2A-B PW3A-B
2
0048914000
CABLE RIBBON 8 CKT 7 in
PW100-101
2
0026517001
CAP AE AX 2.2uF 50V 20%
C7 C38
5
0038691001
CAP AE AX 4.7uF 50V 20%
C2 C5 C11 C19 C24
3
0038692001
CAP AE AX 10uF 35V 20%
C58-60
5
0025960001
CAP AE AX 22uF 16V 20%
C41 C44-46 C52
6
0042001001
CAP CA 33pF 100V LL
C6 C10 C18 C23 C30 C57
1
0039256001
CAP CA 68pF 100V LL
C39
2
0039258001
CAP CA 180pF 100V LL
C1 C25
1
0039261001
CAP CA 330pF 100V LL
C56
1
0039262001
CAP CA 680pF 50V LL
C32
16
0034788003
CAP CR .1uF 50V 20% .2” LS
C61-76
2
0027255003
CAP MPF .001uF 100V 10%
C16 C37
2
0027257003
CAP MPF .0022uF 100V 10%
C17 C40
3
0027259003
CAP MPF .0033uF 100V 10%
C13 C29 C35
1
0027260003
CAP MPF .0039uF 100V 10%
C55
1
0027261003
CAP MPF .0047uF 100V 10%
C22
2
0027262003
CAP MPF .0068uF 100V 10%
C8-9
2
0027264003
CAP MPF .01uF 100V 10%
C21 C33
1
0041904003
CAP MPF .012uF 100V 10%
C15
1
0027265003
CAP MPF .015uF 100V 10%
C12
1
0041903003
CAP MPF .018uF 100V 10%
C14
2
0027270003
CAP MPF .033uF 100V 10%
C27-28
5
0027272003
CAP MPF .047uF 100V 10%
C42-43 C47-48 C51
2
0027278003
CAP MPF .1uF 63V 10%
C3-4
1
0027281003
CAP MPF .22uF 63V 10%
C36
3
0027283003
CAP MPF .33uF 63V 10%
C26 C53-54
3
0027286003
CAP MPF .47uF 63V 10%
C20 C49-50
1
0030942003
CAP PFF RDL .0056uF 50V 5%
C31
10
0027945000
CONTROL SNAPIN 100k B TAPER
R13 R17 R34 R37 R39 R41 R43 R48 R94
R120
Gain RoomBalance Bass Treble LowLevel MidLevel
HighLevel EqGain Compressor MasterVolume
1
0031089000
CONTROL SNAPIN 100K 10C DUAL
R63
MidFreq