Operating instructions
The
following information
is
provided
to
help troubleshoot
this
instrument
.
Information contained
in
other
sections
of
this
manual
should
be
used
along
with
the
following information
to
aid
in
locating
the
defective
component
.
An
understanding
of
the
circuit
operation
is
very
helpful
in
locating
troubles,
particularly
where
integrated
circuits
are
used
.
TROUBLESHOOTING
AIDS
four
significant
digits
of
the
JEDEC
or
vendor
number
using
the
resistor
color-code
system
(e
.g .,
a
diode
color
Diagrams
coded
yellow-brown-green-red
indicates
a 1
N-4152
diode)
.
Circuit
diagrams
are
given
on
foldout
pages
in
Section
8
.
The
component
number
and
electrical
value
of
each
com-
ponent
in
this
instrument
is
shown
on
the
diagrams
.
Components
that
are
mounted
on
circuit
boards
are
out-
Insulated
wire
and
cable
used
in
this
instrument
is
color-
lined
on
the
diagrams
with
a
heavy
black
line
.
coded
to
facilitate
circuit
tracing
.
Voltages
and
Waveforms
Typical
operating
voltages
are
shown
on
the
diagrams
.
Voltage
Conditions
given
on
the
diagram
page
indicate
the
test
equipment
used
and
the
front-panel
control
status
necessary
to
obtain the
given
voltages
.
Typical
operating
waveforms
are
shown
next
to
the
diagram
where
they
were measured
.
Each
waveform
is
numbered
to
locate
on
the
diagram
the
point
where
the
waveform
was
taken
.
Waveform
Conditions
given
on
the
diagram
page
list
the
test
equipment
used
and
the
front-panel
control
status
necessary
to
obtain the
given
waveform
.
Circuit-Board
Illustrations
Circuit-board
illustrations
are
shown
on
the
foldout
page
preceding
the
associated
diagram
.
Each board-mounted
electrical
component
is
identified
by
its
circuit
number,
as
are
interconnecting
wires
and
connectors
.
Figure
8-2,
in
the
front
of
the
diagrams
section,
shows
the
location
and
assembly
number
of
each
circuit
board
in this
instrument
.
Switch
Cam
Identification
Switch
cam
numbers
shown
on
diagrams
indicate
the
posi-
tion
of
each
cam
in
the
complete
switch
assembly
.
The
switch
cams
are
numbered
from
front
to
rear
.
Diode
Color
Code
The
cathode
end
of
each
glass-encased
diode
is
indicated
by
a
stripe,
a
series of
stripes,
or
a
dot
.
The
cathode
and
anode
ends
of
metal-encased
diodes
are
identified
by
the diode
symbol
marked
on the
case
.
For
most
silicon
or
germanium
diodes
with
a
series
of
stripes,
the
color
code
identifies
the
TROUBLESHOOTING
Wiring
Color
Code
Semiconductor
Basing
Figure
4-2
illustrates
the
basing
configurations
for
all
semi-
conductors
used
in
this
instrument
.
Some
plastic-case
transistors
have
lead
configurations
that
do not
agree
with
those
shown
here
.
If
a replacement
transistor
is
made
by
a
different
manufacturer
than
the
original,
check
the
manu-
facturer's
basing
diagram
.
All
transistor
sockets
in
this
instrument
are
wired
for the
standard
basing
used
for
metal-
case
transistors
.
Inter-Board
Pin
Connector
Identification
Maintenance-71380
The
inter-board
pin
connector
sockets
are
installed
on
cir-
cuit
boards,
in
groups
of
5
sockets
(as
in
Figure 4-3)
.
Socket
number
1
is
indexed
on the
circuit
board
with
either
a
triangular
mark
or
the
number
1
.
Each group of
sockets
is
identified
by
its
J
(jack)
number
etched
on
the
circuit
board
.
The
J
numbers
correlate
to
the
J
(jack)
and
P
(plug)
circuit
numbers
on
the
schematic diagrams
.
Multi-Pin
Connector
Identification
Multi-pin
connectors
mate
with
groups
of
pins
soldered
to
circuit
boards
.
Pin
number
1
is
indexed
with
a
triangular
mark
on
the
circuit
board
and
molded
on
the holder
of
the
multi-pin
connector,
as
shown
in
Figure 4-4
.
Each
group
of
pins
is
identified
by
its
corresponding
J
number
etched
on
the
circuit
board
.
The
J numbers,
on
the
circuit
boards,
correlate
to
the
J
and P
component
numbers
on
the
sche-
matic
diagrams
.
Interface
Connector
Pin
Locations
The
Interface
circuit
board
couples
the
plug-in unit
to
the
associated
mainframe
(oscilloscope)
.
Figure 4-5
identifies
the
pins
on
the
interface
connector
as
shown
on
Interface
Connectors
and
Power
Supply
diagram 8
in
the
Diagrams
section
.
4-
3