Fender Bassman Bassman 100 Service Manual - Service Notes

BASSMAN 100

SERVICE NOTES

1.

HORN REPLACEMENT requires speaker removal in order to access horn wiring.  If wire ties,

clamps, etc. are removed for ease of connecting/disconnecting horn wires, these must be replaced to

prevent buzzing at higher power levels.

2.

RIBBON CABLES running between rear panel board and preamp board should be routed next to

the chassis, underneath the power-amp board.

3.

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 toward the rear just far enough to provide

access to the speaker wiring.  Note: the speaker wires are bundled and shrink-wrapped with the

power transformer secondary wiring, and this configuration must be restored after servicing (for

safety compliance).  Locate the speaker wires (white goes to P1, black goes to P2 of the power-amp

board) and disconnect them.  It will be necessary to cut the shrink wrap (take care not to cut the

transformer wires) so that the speaker wires can be pulled from the opening in the bottom of the chassis.

It should be noted that the speaker wires have been glued in place inside the speaker baffle (for sound

quality reasons), if this is disturbed during disassembly, it should be restored by removing the speaker, and

working through the speaker hole; leave sufficient slack to allow reassembly of the speaker leads to the

chassis.

For reference, the red wires from the transformer go to P3 & P5.  The red/yellow wire goes to P4.

PARTS LIST

NOTE: SHADED ITEMS ARE FOR REFERENCE ONLY

PRINTED CIRCUIT BOARD ASSEMBLY - PREAMP

QTY     PART #        DESCRIPTION                                         REFERENCE  DESIGNATION       

1

26517001

CAP AE AX 2.2uF 50V 20%

C40

2

38691001

CAP AE AX 4.7uF 50V 20%

C2 C6

9

25960001

CAP AE AX 22uF 16V 20%

C5 C13 C20 C25-27 C30-31 C33

1

38693001

CAP AE AX 47uF 16V 20%

C64

4

42001001

CAP CA 33pF 100V LL

C8 C19 C21 C32

1

39256001

CAP CA 68pF 100V LL

C22

1

38699001

CAP CA 100pF 100V LL

C39

2

39261001

CAP CA 330pF 100V LL

C11 C37

2

38703001

CAP CA .1uF 50V

C38 C41

2

51405003

CAP CD 120pF 500V 5%

C28-29

1

51960003

CAP CD 180pF 500V 10%

C1

16

34788003

CAP CR .1uF 50V 20% .2" LS

C44-45 C52-63 C65-66

1

27256003

CAP MPF .0015uF 100V 10%

C10

1

27257003

CAP MPF .0022uF 100V 10%

C23

1

27259003

CAP MPF .0033uF 100V 10%

C17

2

27260003

CAP MPF .0039uF 100V 10%

C36 C67

1

27261003

CAP MPF .0047uF 100V 10%

C18

1

27262003

CAP MPF .0068uF 100V 10%

C12

1

27264003

CAP MPF .01uF 100V 10%

C15