JVC HR-D540EE - Mechanism Adjustments

1.2 MECHANISM ADJUSTMENTS
1.2.1
1.
Precautions
Disconnect
mainframe
from
AC
power
before
soldering.
2.
Avoid
imparting
stress
to
wires
when
disengaging
con-
>
1.2.2
nectors.
.
Determine
and
correct
the
cause
of
difficulty
before
proceeding
to
adjustments.
Do
not
disturb
settings
un-
necessarily.
Use
care
not
to
damage
tabs,
claws,
etc.
during
repairs.
_
Install
the
cassette
housing
assembly
only
when
the
mechanism
is
in
the
Eject
or
Stop
mode
position.
In
the
Eject
mode,
the
internal
holder
of
the
housing
is
fully
raised.
This
is
fully
lowered
in
the
Stop
mode.
. When installing the front panel assembly, be sure to
engage
the
housing
door
with
the
door
lever
of
the
cassette
housing
assembly.
If
this
is
omitted,
the
door
will
not
open
at
Eject
and
the
cassette
cannot
be
removed.
Check without cassette housing
Mechanism operations can be observed easily by removing
the cassette housing assembly. Note the following.
1,
Alignment tapes
1
1-4
Disable the photo transistor sensor (END SENSOR) on
the main-deck by applying an opaque cover.
. Connect pins 2 and 3 of Main board connector CN601.
. Select the desired modes with the operation buttons.
However, notice that without tape, setting for the reverse
direction modes produces the Stop mode after a few
seconds due to absence of the ree! sensor output.
Torque gauge
3
1.2.3. Manually removing cassette tape
In event of electrical system failure that prevents the tape
from being unloaded, the tape can be removed manually by
the following procedure. Refer to Figs. 1-3-1, 1-3-2 and
1-3-3.
1,
2.
Disconnect power cord from AC outlet.
Turn the loading motor by hand so that the control cam
rotates clockwise. This retracts the pole base assembly to
the unloading position.
. Continue turning to where the guide arm and half load-
ing gear assemblies shift to beneath the cassette.
. Turn the clutch assembly (capstan motot) at the rear of
the deck to absorb slack tape within the cassette.
. Again turn the loading motor in the same direction to
raise the cassette and remove it.
1.2.4 Test equipment
The following special tools and fixtures are required for
mechanism adjustment.
1.
3.
Alignment tape : MH-2
Stairstep signal is employed for interchangeability checks
and adjustments.
. Torque gauge : PUJ48075-2
Measures tape take-up torque.
Back tension cassette gauge : PUJ48076-2
Measures tape tension at the supply side.
4.‘A/C head positioning tool : PUJ47351-2
5.
Back tension cassette gauge
Shifts the head base for adjusting the control head posi-
tion.
Roller driver : PTU94002
Turns the guide roller for adjusting FM linearity.
A/C head positioning tool Roller driver
Fig. 1-2-4 Test equipment