Operating instructions
Maintenance-788°7
SWITCHES
4-
1
2
Figure
4-9
.
Location
of
securing
screws and
inter-board
multi-pin
connectors
on clock
circuit
board
.
3
.
Install
gray
plastic
rear
panel
with
4
securing
screws
.
4
.
Replace
TIME/DIV
knob
on
shaft
.
Align
knob
index
with
2
ms
position
;
then,
tighten
2 set
screws
on
knob
.
5
.
Replace
VARIABLE
knob
and
tighten set
screw
.
6
.
Replace
all
cables
as
noted
during
removal
procedure
.
7
.
Replace
Trigger
and
Clock
circuit
boards
.
Two
types
of
switches
are
used
in
this
instrument
.
Contact
alignment and
spacing
are
critical
to
the
operation
of
the
pushbutton
and
cam
switches
.
Therefore,
defective
switches
should
either
be
replaced
as
a unit or
repaired
only
by
personnel
experienced
with
these
types
of
switches
.
Your
local
Tektronix
Field
Office
or
representative
can
provide
additional
repair
information
.
The
following
special
maintenance
information
is
provided
for
switch
replacement
.
INTER-BOARD
MULTI-PIN
CONNECTORS
CAM
SWITCHES
.
Cam
switches
consist
of
a
rotating
cam
that
mates
with
contacts
on
the
adjacent
circuit
board
.
These
contacts
are activated
by
lobes
on
the
care
as
the
switch
is
rotated
.
A
cam
switch can
be
disassembled
for
inspection,
cleaning,
repair,
or
replacement
;
however,
it
is
recommended
that
the
switch
be
removedand
replaced
as
a
unit
.
Refer
to
Figure
4-10
for special instructions
on
cam
switch
removal
.
Repair
of
a
cam
switch
should
be
undertaken
only
by
experienced
maintenance
personnel
.
Switch
alignment
and
contact
spacing
must
be
carefully
maintained
for
proper
operation
.
A
cam
switch
repair
kit
is
available
(Tektronix
part
040-0541-00)
which
contains
special
alignment
tools
for
use
in
repairing
or
replacing
the
switch
contacts
.
For
information
or
assistance
on
maintenance
of
cam
switches,
contact
your
local
Tektronix
Field
Office or
representative
.
2788-62