JVC TM-1500PS User Manual

SAFETY
PRECAUTIONS
The design of this product contains special hardware, many
circuits and components specially for safety purposes.
For continued protection, no changes should be made to the
original design unless authorized in writing by the manufactur-
er. Replacement parts must be identical to those used in the
original circuits. Service should be performed by qualified per-
sonnel only.
Alterations of the design or circuitry of the products should not
be
made.
Any
design
alterations
or
additions
will
void
the
manufacturer's
warranty
and
will
further
relieve
the
manufac-
turer
of
responsibility
for
personal
injury
or
property
damage
resulting therefrom.
Many electrical and mechanical parts in the products have
special safety-related characteristics. These characteristics are
often not evident from visual inspection nor can the protection
afforded
by
them
necessarily
be
obtained
by
using
replace-
ment components rated for higher voltage, wattage, etc. Re-
placement
parts
which
have
these
special
safety
characteris-
tics
are
identified
in
the
parts
list
of
Service
manual.
Electri-
cal components having such features are identified by
shading
on
the
schematics
and
by
(
4\)on
the
parts
list
in Service manual. The use of a substitute replacement
which does not have the same safety characteristics as the
recommended replacement part shown in the parts list of Ser-
vice manual many create shock, fire, or other hazards.
Don’t short between the LIVE side ground and NEU-
TRAL
side
grounding
or
EARTH
side
ground
when
re-
pairing.
Some model’s power Circuit is partly different in the GND. The
difference
of
the
GND
is
shown
by
the
LIVE
(1)
side
GND,
the NEUTRAL( »-) side GND and EARTH ( ®) side GND.
Don’t
short
between
the
LIVE
side
GND
and
NEUTRAL
side
GND or EARTH side GND and never measure with a mea-
suring apparatus (oscilloscope etc.) the LIVE side GND and
NEUTRAL
side
GND
or
EARTH
side
GND
at
the
same
time.
if above note will not be kept, a fuse or any parts will be
broken.
lf any repair has been made to the chassis, it is recommended
that the B1 setting should be checked or adjusted (See AD-
JUSTMENT OF B, POWER SUPPLY).
The high voltage applied to the picture tube must conform with
that specified in Service manual. Excessive high voltage can
cause an increase in X-Ray emission, arcing and possible
component damage, therefore operation under excessive high
voltage conditions should be kept to a minimum, or should be
prevented.
If
severe
arcing
occurs,
remove
the
AC
power
im-
mediately
and
determine
the
cause
by
visual
inspection
(incor-
rect installation, cracked or melted high voltage harness, poor
soldering,
etc.).
To
maintain
the
proper
minimum
level
of
soft
X-Ray emission, components in the high voltage circuitry in-
cluding the picture tube must be the exact replacements or al-
ternatives approvided by the manufacturer of the complete
product.
Do not check high voltage by drawing an arc. Use a high volt-
age meter or a high voltage probe with a VTVM. Discharge
the picture tube before attempting meter connection, by con-
necting a clip lead to the ground frame and connecting the
other end of the lead through a 10kQ 2W resistor to the an-
ode button.
When service is required, observe the original lead dress. Ex-
tra
precaution
should
be
given
to
assure
correct
lead
dress
in
the
high
voltage
circuit
area.
Where
a
short
circuit
has
oc-
curred, those components that indicate evidence of overheat-
ing should be replaced. Always use the manufacturer's re-
placement components.
9.
(1)
(2)
| TM-1500PS
Isolation Check
(Safety for Electrical Shock Hazard)
After
re-assembling
the
product,
always
perform
an
isolation
check
on
the
exposed
metal
parts
of
the
cabinet
(antenna
ter-
minals,
video/audio
input
and
output
terminals,
Control
knobs,
metal
cabinet,
screwheads,
earphone
jack,
control
shafts,
etc.)
to
be
sure
the
product
is
safe
to
operate
without
danger
of
electrical
shock.
Dielectric Strength Test
The isolation between the AC primary circuit and all metal
parts
exposed
to
the
user,
particularly
any
exposed
metal
part
having a return path to the chassis should withstand a voltage
of 3000V AC (r.m.s.) for a period of one second.
(... . Withstand a voltage of 1100V AC (r.m.s.) to an appli-
ance
rated
up
to
120V,
and
3000V
AC
(r.m.s.)
to
an
appli-
ance rated 200V or more, for a period of one second.)
This method of test requires a test equipment not generally
found in the service trade.
Leakage Current Check
Plug the AC line cord directly into the AC outlet (do not use a
line isolation transformer during this check.) Using a "Leakage
Current
Tester”,
measure
the
leakage
current
from
each
ex-
posed
metal
part
of
the
cabinet,
particularly
any
exposed
metal
part
having
a
return
path
to
the
chassis,
to
a
known
good
earth ground (water pipe, etc.). Any leakage current must not
exceed 0.5mA AC (r.m.s.).
© Alternate Check Method :
Plug the AC line cord directly into the AC outlet (do not use a
line isolation transformer during this check.). Use an AC volt-
meter having 1,000 ohms per volt or more sensitivity in the
following manner. Connect a 1,5002 10W resistor paralleled
by a 0.15pF AC-type capacitor between an exposed metal
part and a known good earth ground (water pipe, etc.). Mea-
sure
the
AC
voltage
across
the
resistor
with
the
AC
voltmeter.
Move the resistor connection to each exposed metal part, par-
ticularly any exposed metal part having a return path to the
chassis, and measure the AC voltage across the resistor.
Now, reverse the plug in the AC outlet and repeat each mea-
surement, Any voltage measured must not exceed 0.35V AC
(r.m.s.). This corresponds to 0.5MA AC (r.m.s.).
AC VOLTMETER
(HAVING 10002/V,
OR MORE SENSITIVITY)
PLACE THIS PROBE
ON EACH EXPOSED
METAL PART
i 15002 10W
GOOD EARTH GROUND
Fig.A
(No.50343) 3

JVC TM-1500PS Specifications

General

Brand	JVC
Model	TM-1500PS
Category	Monitor
Language	English