Tektronix 5103N

System Maintenance—
51 03N
3.
Remove
the
screws
(from the
opposite
side of the
circuit
board)
which hold the
cam
drum to the
board.
4.
To
remove
the cam
drum
from the
front support
block,
remove the
retaining
ring
from the
shaft
on
the front
of the
switch
and slide
the cam
drum
out
of the support
block.
Be
careful not to lose the
small
detent roller.
5.
To
replace
defective
switch contacts,
follow
the in-
structions
given in the
switch repair
kit.
6.
To
re-install
the
switch
assembly, reverse the above
procedure.
B.
PUSHBUTTON
SWITCHES
The
pushbutton
switches are
not
repairable and should
be
replaced as a
unit
if defective.
Use a suction-type
de-
soldering
tool to
remove solder
from the holes in
the circuit
board when
unsoldering the
switches.
Cathode-Ray
Tube
Replacement
The
following
procedure
outlines the
removal and
re-
placement
of the
cathode-ray
tube.
Refer
to
Fig.
4-3.
WARNING
I
Use care
when
handling a CRT.
Protective
clothing
and safety
glasses
should be
worn.
Avoid striking it
on any
object
which
might cause
it
to
crack or im-
plode. When
storing a CRT,
place it
in a
protective
carton or set
it face
down in a
protected
location on a
smooth
surface
with a
soft mat under
the
faceplate
to
protect it
from
scratches.
A.
REMOVAL:
1.
Remove
the
bezel
assembly,
which
is held
in
place
with
two screws.
(The
bezel
assembly
includes
a
snap-in
implosion
shield.)
2.
For
storage
CRT's
(Dll,
D13),
disconnect the
storage-element
cable
connector
from the
Storage
circuit
board.
For
dual-beam
CRT's
(D12, D13),
disconnect de-
flection leads
from neck
pins.
NOTE
The red
and
black wires
entering the
CRT
shield are
connected to
the
trace-rotation
coil
inside
the shield.
Fig.
4-3.
Replacing
the cathode-ray
tube.
They will not hamper CRT
removal and need not be
unsoldered.
3.
Remove the CRT base
cover on the rear panel
of
the
instrument.
4.
Remove
the CRT base
socket.
5. Loosen the CRT clamp.
The
CRT and neck
portion
of the
shield will be
removed as a unit,
and
to
facilitate
removal, it may
be best
to remove all
hardware
from the
CRT
clamp
(bracket
and positioning
screws, and clamp-
tightening
hardware).
6.
With one
hand
on the
CRT
faceplate, push
on
the
CRT base
(and
neck shield). Slide the
CRT and
neck
shield
forward, and at the same
time feed
the
storage-element
4-7