HP 8340b User Manual

17.
Pull
the
reference
loop
—
M/N
loop
casting
out
of the
instrument.
18. Inspect
the
bare
contacts
on
the
main instrument
motherboard before
installing
the
new
reference
loop
—
M/N
loop motherboard/casting
assembly.
Make
sure
they
are
clean and free
of
dirt,
grit,
metal
shavings, or
any
other
type
of
foreign
material.
Inspect
the
connectors
on
the
bottom
of
the
new
motherboard/casting
assembly,
make sure
they
are
not
damaged
or
bent.
Install
the
new
motherboard/casting
assembly
so
its
contacts
are
oriented
the
same way
as
those
on
the
main
instrument
motherboard.
On
the
top
of the
instrument, replace
the
8
screws
removed
In
step
14.
Refer
to
Figure
B-23.
Reinstall the
A29, A30,
A31,
and
ASS
assemblies,
along
with
the
28
retaining
screws.
Reconnect
all
cables.
(Refer
to
Figure
B-24
if
necessary.)
Reinstall
the
A19
capacitor
Assembly
19. Note
that
one
end
of
the
capacitor
assembly
has
two
tabs,
or flanges,
with
one
screw
hole
in
each.
This
end
should
be lowered
into
the
instrument
first,
so
the
other
end
will
not
hit
the side
panel.
Press
the
P.C.
board fingers
of the
A19
assembly
into the
connector
on
the
main instrument
motherboard.
20.
Refer
to
VIEW
A
and
C.
With
a
large pozidriv,
install
the
four
screws,
items
15
and
16.
Reinstall
the
RF
deck
21.
Place
the
RF
deck
hinge
on
the
standoffs
it
attaches
to.
Make
sure
ribbon
cable
W29
(shown
in
VIEW
C)
runs
under
the RF
deck,
between
the
two
standoffs
nearest
the
center
of
the
instrument.
Make
sure
the ribbon
cable
is
not pinched
between
the
RF
deck
and the standoffs
when screwing
the
hinge
in
place
(next
step).
22.
Refer
to
VIEW
C.
With
a
small
pozidriv,
install
the
5
RF
deck
hinge
screws,
item
14.
Plug
the
W29
ribbon
cable
into
the
sockets
on
the
A20
and
A16
assemblies.
23.
Refer
to
VIEW
D.
Reinstall
the
ribbon
cable
which
was
previously removed from
the
A13
SYTM.
Be
sure
to
orient
the
ribbon
connector
so
that
pin
1
of
the
connector
and
pin
1
of
the
A13J1
socket
are
aligned.
The
socket
is
of
the
variety
normally
used
to
hold
integrated
circuits,
and
pin
1
is
oriented
just
as
it
would be for
an
integrated
circuit.
24.
Refer
to
VIEW
B.
Swing
the
RF
deck
into
its
closed
position,
being
careful
not
to
pinch
the
A13
SYTM
ribbon
cable
and
that
the
various
disconnected
semi-rigid cables
(W14
and
W16
shown
in
VIEW
B,
and
W13
shown
in
VIEW
C)
are
not
damaged
by
hitting
microcircuit
assemblies.
25.
Reconnect
all
cables disconnected
in
step
9.
Refer
to
VIEW
C.
To
minimize signal
leakage,
lay
cables
W23
(A8-100
IN)
and
W24
(A8-MOD
IN)
well
away
from
the
A16
assembly.
26.
Reverse
steps
7
through
1
of
this
procedure.
B-48
Reference Loop
-
M/N
Loop
Repair
Procedures
HP 8340B/41B

HP 8340b Specifications

General

Brand	HP
Model	8340b
Category	Inverter
Language	English