Samsung MM-77 User manual

MICRO
COMPONENT
SYSTEM
MM-77
S
ERVIC
Manual
i
MICRO COMPONENT SYSTEM
APF CCAUT ON -csateistans doce Sale dtaaaroeeeacsanrs 1~9
2; SDOCITICATION a:iinescetcctevecdav unten 10
3. Location of controls ........ccee 11~13
4. Disassembly instruction............ 14~15
5. Basic circuit operation............... 16~17
6. TroubleSHOOTING ......ecceseeeeeeeees 18~26
FAQUUSUMIENT siasrmiccihddiariereds 27~32
8. Block diagram........ccessseseseees 33~34
a
—
“SSE
vec
]
9.Exploded
view
&
parts
list........
35~41
10.Schematic diagram... 42~44
11.PCB Pattern and Marking
HAGMAN asia ste senetuetrsannslncensadagenas 45~48
12. Wiring diagram .....cccccccseseeeeeeeeens 49
13.IC & TR internal diagram .......... 50~57
14. Electrical parts list... eee 58~67
15. List of Abbreviation ..........cccceeeees 68
*Design
and
specification
are
subject
to
change
upon
improvement
without
prior notice.

1. Safety precaution
1-1. Class 1 laser product
This laser disc player is classified as a CLASS 1 laser product.
1-2. Laser warning label
The label shown below may be affixed or not according to country.
(UL) (CSA) (EU)
This Product Complies with CERTIFIED ONLY TO CANADIAN
DHHS Rules 21CFR, Sub ELECTRICAL CODE.
chapter J.At date of Manu- CLASS 1
facture CERTIFIE EN VERTU DU CODE LASER PRODUCT
CANADIAN DE LELETRICITE
SEULEMENT
L
Location: Enclosure back.
(SCAN)
CAUTION ! invisi8Le LASER RADIATION WHEN OPEN
AND INTERLOCKS DEFEATEO AVOIDEXPOSURE TO BEAM (EU)
ADVARSEL USYNLIG LASERSTRALING VED ABNING
NAR SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION
UL : Manufactured for U.S.A. Market.
CSA __ : Manufactured for Canadian Market.
UNDGAUDSAETIELSE FOR STRAUNG EU : Manufactured for European Market.
VARO:AVATTAESSA JA SUOJALUKITUS OHITETTAESSA ; ‘
OLET ALTTINA NAKYMATTOMALLE LASERSATEILYLLE ALA SCAN : Manufactured for Scandinavian
KATSO SATEESEEN! Market
arket.
VARNING\OSYNUG LASERSTRALNING NAR DENNA DEL
AR OPPNAD OCH SPARREN AR URKOPPLAD BETRAKTA
EJSTRALENI
Location : on the disc clamper or inner side of UNIT door or nearby UNIT chassis.
1-3.Laser beam warning
1-4.
1-5.
ADVERSEL -Usynlig saserstraling ved abning, nar Sikkerhedsafbrydere er ude af funktion.
Undga udsaettelse for straling.
VARNING -Osylig laserstralning nar denna del ar Gppnad och sparr ar urkopplad. Stralen ar farlig.
VARITUS -Laite sisaltaa laserdiodin, joka lahettaa nakymatonta silmille vaarallista lasersateilya.
CAUTION -Invisible laser radiation when door is open and interlocks defeate. Avoid exposure to
beam.
Laser diode specification (Optical pick-up)
¢ Material : GaAs+GaAlAs
* Wavelength : 760-800nm
* Emission duration : Continuous
* Laser Output : 0.2mW
* This output is the value measured at distance 1.6mm from the objective lens surface on the optical pick-
up block.
* Classification : CLASS 1
Warning for servicing
WARNING: When servicing, do not approach the LASER exit with the eye too closely. In case it is necessary
to confirm LASER beam emission, be sure to observe from a distance of more than 30cm from
the surface of the objective lens on the optical pick-up block.
VARNING: Nar underhailningsarbeten utfors, narma dig forsiktigt och se inte pa laserutstralningen pa for
nare hall. If all det ar n6dvandigt att betrygga laserstralens utstromning. Var saker att kontrollera
detta fran ett avstaand av mer an 30cm (11.81 inch.) fraan den objektiva linsens yta pa den
optiska utsandningspunkten.
ADVARSEL: Nar repareringsarbejdet udfoeres, naerm dig forsigtigt og se ikke pa laserudstralingen paa for
naer haand. “t ilfaeldet at det er noedvaendigt at bestemme laserstralens udstraling. Vaer sikker
pa kontrollere dette fra en afstand af mere end 30cm (11.81 inch.) fra den objektive linses
overflade pa den optiske udsendningspunkt.
VAROITUS: Silmia on varottava viemasta liian labeile laser-poistokanavaa huoiion aikana. Jos on
valttamatonta varmistaa Laser-Sateen paasto, pysyttels sita tarkasteltaessa vahintaan 30cm
etaiyydella optisen lukon objecktiivilinssin pinnasta..
MM-77 —1—

1-1-6.
(2
—
(3)
MM-77
Before
returning
an
instrument
to
the
customer,
always
make
a
safety
check
of
the
entire
instrument,
including,
but
not
limited
to,
the
following
items:
Be
sure
that
no
built-in
protective
devices
are
defective
or
have
been
defeated
during
servicing.
(1)
Protective
shields
are
provided
to
protect
both
the
technician
and
the
customer.
Correctly
replace
all
missing
protective
shields,
including
any
remove
for
servicing
convenience.
(2)
When
reinstalling
the
chassis
and/or
other
assembly
in
the
cabinet,
be
sure
to
put
back
in
place
all
protective
devices,
including,
but
not
limited
to,
nonmetallic
control
knobs,
insulating
fishpapers,
adjustment
and
compartment
covers/shields,
and
isolation
resistor/
capacitor
networks.
Do
not
operate
this
instrument
or
permit
it
to
be
operated
without
all
protective
devices
correctly
installed
and
functioning.
Be
sure
that
there
are
no
cabinet
openings
throught
which
adults
or
children
might
be
able
to
insert
their
fingers
and
contact
a
hazardous
voltage.
Such
openings
include,
but
are
not
limited
to,
excessively
wide
cabinet
ventilation
slots,
and
an
improperly
fitted
and/or
incorrectly
secured
cabinet
back
cover.
Leakage
Current
Hot
Check-With
the
instrume-nt
completely
reassembled,
plug
the
AC
line
cord
directly
into
a
120V
AC
outlet.
(Do
not
use
a
isolation
transformer
during
this
test.)
Use
a
leakage
current
tester
or
a
metering
system
that
complies
with
American
National
Standards
institute
(ANSI)
C101.1
Leakage
Current
for
App-
liances
and
Underwriters
Laboratories
(UL)
1270
(40.7).
With
the
instrument's
AC
switch
first
in
the
ON
positin
and
then
in
the
OFF
position,
measure
from
a
known
earth
ground
(metal
waterpipe,
conduit,
etc.)
to
all
exposed
metal
parts
of
the
instrument
(antennas,
handle
brackets,
metal
cabinets,
screwheads,
metallic
overlays,
control
shafts,
etc.),
especially
any
exposed
metal
parts
that
offer
an
electrical
return
path
to
the
chassis.
Any
current
measured
must
not
exceed
0.5
millamp.
Reverse
the
instrument
power
cord
plug
in
the
outlet
and
repeat
the
test.
See Figure 1.
Any
measurements
not
within
the
limits
specified
herein
indicate
a
potential
shock
hazard
that
must
be
ellminated
before
returning
the
instrument
to
the
customer.
(Reading should
not be above
0.5mA)
Leakahe
Currant
Tester
Test all
exposed metal
surfaces
2-Wire Cord
Also test with
plug reversed
(using AC adapter
plug as required)
FIG. 1 AC Leakage Test
(4)
Insulation
Resistance
Test
Cold
Check-(1)
Unplug
the
power
supply
cord
and
connect
a
jumper
wire
between
the
two
prongs
of
the
plug.
(2)
Turn
on
the
power
switch
of
the
instrument.
(3)
Measure
the
resistance
with
an
ohmmeter
between
the
jumpered
AC
plug
and
all
exposed
metallic
cabinet
parts
on
the
instrument,
such
as
screwheads,
antenna,
control
shafts,
handie
brackets,
etc.
When
an
exposed
metallic
part
has
a
return
path
to
the
chassis,
the
reading
should
be
between
1
and
5.2
megohm.
When
there
is
no
return
path
to
the
chassis,
the
reading
must
be
infinite.
If
the
reading
is
not
within
the
limits
specified,
there
is
the
possibility
of
a
shock
hazard,
and
the
instrument
must
be
repared
and
rechecked
before
it
is
returned
to
the
customer.
See Figure 2.

Antenna
Terminal
Exposed
Melal Part
Ohmmeter
1-1-7.
1-1-8.
1-1-9.
FIG. 2 Insulation Resistance Test
Read and comply with all caution and safety-
related notes non or inside the cabinet, or on
the chassis.
Design Afteration Warning-Do not alter or add
to the mechanical or electrical design of this
instrument. Design alterations and additions,
including but not limited to, circuit
modifications and the addition of items such
as auxiliary audio output connections, might
alter the safety characteristics of this
instrument and create a hazard to the user.
Any design alterations or additions will make
you, the servicer, responsible for personal
injury or property damage resulting
therefrom.
Observe original lead dress. Take extra care to
assure correct lead dress in the following
areas: (1) near sharp edges, (2) near thermally
hot parts (be sure that leads and components
do not touch thermally hot parts), (3) the AC
supply, (4) high voltage, and (5) antenna
wiring. Always inspect in all areas for pinched,
out-of-place, or frayed wiring. Do not change
spacing between a component and the
printed-circuit board. Check the AC power
cord for damage.
MM-77
1-1-10. Components, parts, and/or wiring that
appear to have overheated or that are
otherwise damaged should be replaced with
components, parts and/or wiring that meet
original specifications. Additionally,
determine the cause of overheating and/or
damage and, if necessary, take corrective
action to remove any potential safety
hazard.
Product Safety Notice-Some electrical and
mechanical parts have special safety-related
characteristics which are often not evident
from visual inspection, nor can the
protection they give necessarily be obtained
by replacing them with components rated
for higher voltage, wattage, etc. Parts that
have special safety characteristics are
identified by shading, an (x) or a ( A\,) on sc-
hematisc and parts lists. Use of a substitute
replacement that does not have the same
safety characteristics as the recommended
replacement part might created shock, fire
and/or other hazards. Product safety is under
review continuously and new instructions
are issued whenever appropriate.

2. Servicing notes
2-1. Before servicing the unit
Be
sure
to
observe
the
safety
notes
attached
on
label,
chassis,
cabinet
top,
cabinet
bottom
and
printed
circuit
board.
2-1-1. Caution on laser beammalfunction
Do
not
try
to
access
objective
lens,
when
DISC
is
not
on
the
tray.
When
pick-up
mechanism
replacement
is
required,
be
sure
to
turn
power
off.
2-1-2. When handling parts
Tube,
tape
or
insulating
parts
are
used
for
sepa-ration
or
insulation
purposes.
Especially
parts
which
generate
excessive
heat
are
kept
away
from
PCB
or
any
other
sensitive
parts.
Therefore,
when
replacing
parts,
be
sure
to
replace
them
in
their
original
position.
2-1-3. When fixing wires
Wires
should
be
fixed
in
such
a
way
with
cable-tie
so
they
won't
move.
When
finished
servicing,
be
sure
to
leave
unit
in
it's
original
configuration.
2-1-4. Use specified parts only
The
safety
specification
built
into
the
electronics
of
this
unit
require
that
you
use
specified
parts
only.
Do
not
use
any
other
replacements.
Using
other
parts
can
result
in
electrical
and
fire
hazard.
2-1-5. After servicing is complete
After
servicing
is
complete,
check
if
there
are
any
missing
parts
or
that
wires
are
properly
fixed
and
any
place
where
over
heating
or
shock
is
likely
to
occur,
can
be
found.
short terminal
SOH91C1(CAR, walkman)
SOH91VI(LDP)
MM-77
2-1-6. Handling the optical pick-up
*
The
laser
diode
in
the
optical
pick
up
may
suffer
electrostatic
breakdown
because
of
potential
static
electricity
from
clothing
and
your
body.
The following method is recommended.
(1)
Place
a
conductive
sheet
on
the
work
bench
(The
black
sheet
used
for
wrapping
repair
parts.)
(2)
Place
the
set
on
the
conductive
sheet
so
that
the
chassis
is
grounded
to
the
sheet.
(3)
Place
your
hands
on
the
conductive
sheet
(This
gives
them
the
same
ground
as
the
sheet).
(4) Remove the optical pick up block.
(5)
Perform
work
on
top
of
the
conductive
sheet.
Be
careful
not
to
let
your
clothes
or
any
other
static
sources
to
touch
the
unit.
*
Be
sure
to
put
on
a
wrist
strap
grounded
to
the
sheet.
*
Be
sure
to
lay
a
conductive
sheet
made
of
copper
etc.
which
is
grounded
to
the
table.
4
Mr Pek
SSte5 vee sy,
= cp
Notes
vy aay
* OSES IM ¢ 1M
; ' Pe
APS”
Lr ea a SS
‘0 THE UNIT AA | a
\s WS, Ant a
< A
(1) WRIST-STRAP oe CONDUCTIVE SHEET
FOR GROUNDING 1M f
(6)
Short
the
short
terminal
on
the
PCB,
which
is
inside
the
Pick-Up
ASS'Y,
before
replacing
the
Pick-Up.
(The short terminal is shorted when the Pick-Up
Ass'y is being lifted or moved.)
(7)
After
replacing
the
Pick-up,
open
the
short
terminal on the PCB.
ON
Sal
a
EF)
terminal
SOH-A1
(CMS-V10,CMS-V30)
terminal
SOH94T4N
(CMS-V10,CMS-V30)

2-2. Servicing Precautions
CAUTION: Before servicing Instruments covered by
this service manual and its supplements, read and
follow the Safety Precautions section of this manual.
Note: If unforseen circument create conflict between
the following servicing precautions and any of the
safety precautions, always follow the safety
precautions.
Remember: Safety First.
2-2-1. General Servicing Precautions
(1) a. Always unplug the instrument's AC power cord
from the AC power source before (1) removing
or reinstalling any component, circuit board,
module or any other instrument assembly, (2)
disconnecting any instrument electrical plug or
other electrical connection, (3) connecting a test
substitute in parallel with an electrolytic
capacitor in the instrument.
b. Do not defeat any plug/socket B+ voltage
interlocks with which instruments covered by
this service manual might be equipped.
c. Do not apply AC power to this instrument
and/or any of its electrical assemblies unless all
solid-state device heat sinks are correctly
installed.
d. Always connect a test instrument's ground lead
to the instrument chassis ground before
connecting the test instrument positive lead.
Always remove the test instrument ground
lead last.
Note: Refer to the Safety Precautions section
ground lead last.
(2) The service precautions are indicated or printed
on the cabinet, chassis or components. When
servicing, follow the printed or indicated service
precautions and service materials.
(3) The components used in the unit have a specified
flame resistance and dielectric strength. When
replacing components, use components which
have the same ratings. Components identified by
shading, by (x) or by (.1 ) in the circuit diagram
are important for safety or for the characteristics
of the unit. Always replace them with the exact
replacement components.
MM-77
(4) An insulation tube or tape is sometimes used and
some components are raised above the printed
wiling board for safety. The internal wiring is
sometimes clamped to prevent contact with
heating components. Install such elements as
they were.
(5) After servicing, always check that the removed
screws, corponents, and wiring have been
installed correctly and that the portion around the
serviced part has not been damaged and so on.
Further, check the insulation between the blades
of the attachment plug and accessible conductive
parts.
2-2-2. Insulation Checking Procedure
Disconnect the attachment plug from the AC outlet
and turn the power ON. Connect the insulation
resistance meter (500V) to the blades of the
attachment plug. The insulation resistance between
each blade of the attachment plug and accessible
conductive parts (see note) should be more than 1
Megohm.
Note: Accesible conductive parts include metal
panels, input terminals, earphone jacks, etc.

2-3. ESD, Precautions
Electrostatically SensitiveDevices (ESD)
Some semiconductor (solid state) devices can be
damaged easily by static electricity.
Such components commonly are called Electro-
statically Sensitive Devices (ESD). Examples of typical
ESD devices are integrated circuits and some field-
effect transistors and semiconductor chip com-
ponents. The following techniques should be used to
help reduce the incidence of component damage
caused by static electricity.
(1) Immediately before handling any semiconductor
component or semiconductor-equipped
assembly, drain off any electrostatic aharge on
your body by touching a known earth ground.
Alternatively, obtain and wear a commercially
available discharging wrist strap device, which
should be removed for potential shock reasons
prior to applying power to the unit under test.
(2) After removing an electrical assembly equipped
with ESD devices, place the assembly on a con-
ductive surface such as aluminum foil, to prevent
electrostatic charge buildup or exposure of the
assembly.
(3) Use only a grounded-tip soldering iron to solder
or unsolder ESD devices.
(4) Use only an anti-static solder removal device.
Some solder removal devices not classified as
"anti-static" can generate electrical charges
sufficient to damage ESD devices.
(5
—
Do not use freon-propelled chemicals. These can
generate electrical charges sufficient to damge
ESD devices.
MM-77
(6) Do not remove a replacement ESD device from its
protective package until immediately before your
are ready to install it. (Most replacement ESD
devices are packaged with leads electrically
shorted together by conductive foam, aluminum
foil or comparable conductive materials).
(7) Immediately before removing the protective
materials from the leads of a replacement ESD
device, touch the protective material to the
chassis or circuit assembly into which the device
will be installed.
CAUTION: Be sure no power is applied to the
chassis or circuit, and observe all other safety
precautions.
@
Minimize bodily motions when handling unpack-
aged replacement ESD devices. (Otherwise
harmless motion such as the brushing together
of your clothes fabric or the lifting of your foot
from a carpeted floor can generate static
electricity sufficient to damage an ESD device).

3. Chip replacement
3-1. Precaution for the Chip Replacement
(1)Do not touch the part body directly with the
soldering iron. ICS, especially TSOP, are easily
damaged by heat.
(2) Use care regarding soldering iron tip and avoid
rapidly heating parts. Some parts can be
damaged by sudden heating. Preheat the part at
about 100°C for several minutes before installing
it.
(3) Use soldering tip temperature of about 240°C or
larger
parts,
use
a
slightly
higher
temperature
(about 280°C).
(4) The thin (0.3mm) solder for miniature parts does
not contain adequate flux. Supplementary flux is
thus needed in most cases.
The
NoteMaster
486S/25N
series
systems
are
manufactured
using
flux
which
can
be
cleaned
by
water
in
the
factory.
When
your
replace
the
part
or
troubleshooting,
use
proper
flux
and
solder
which
can
be
cleaned
by
water.
Soldering
area
will
corrode,
if
proper
flux
and
solider
are
not
used
in
replace.
And
it
may
cause
a
fatal
error
to
the
system.
(5) Use care not to damage the circuit pattern,
especially when removing.
(6) Because of the many pins, cleanliness of the
pattern is extremely important after removing
the IC.
(7) Use care to avoid solder bridges. Remove any
that occurs.
(8) Position the part carefully. This will also affect the
soldering operation. Be very precise in
positioning the IC. Soldering opposite pins first
holds the IC in place and makes soldering the
other pins easier.
(9) Do not reuse removed parts.
(10) Check for solder joints, especially miniature parts
with small lead.
(11) A defective trimming resistor cannot be adjusted
externally. Replace with an ordinary variable
resistor.
(12) It is important to inspect the work with a
magnifier. Check after installing (cold solder
joints, etc).
3-2.
Tools
for
the
Chip
Replacement
The
tools
for
the
chip
replacement
are
as
follows:
(1) Thin tip type soldering iron
(2) Small flat-blade tip type soldering iron
(3) Special desoldering tip iron
(4) Airblower unit
(5) Flat Package Pick-up
MM-77
6) Flux can be cleaned by water
7)
0.3mm
thin
solder
can
be
cleaned
by
water
8)
Desoldering
wire
9) Tweezers
3-3.
Chip
Resistors
and
Chip
Capacitors
3-3-1.
Kind
jof
the
Part
The
kind
of
chip
resistors
and
chip
capacitors
as
follows
(1) Thick Film Chip Resistors
(2) Carbon Film Chip Resistors
(3) Metal Film Chip Resistors
(4) Chip Ceramic Capacitors
(5) Chip Trimming Resistors
3-3-2. Removing the Part
The
kind
of
chip
resistors
and
chip
capacitors
as
follows
(1) Using two soldering irons:
(D Use thin tip soldering irons.
)
Use
soldering
tip
temperature
of
about
280°C
@) Simultaneously heat both ends of the part.
@
While
heating,
grasp
the
part
with
the
tips
of
the
soldering
irons
and
remove
it.
©)
Use
desoldering
wire
to
completely
remove
the
old
solder
from
the
part
location
of
the
board.
©
A
clean
pattern
for
installing
the
new
part
is
very
important.
FIG, 4
3-3-3. Installing the Part
(1)
Clean
the
area
where
the
new
part
is
to
be
mounted.
(2) Apply flux.
(3) Set part correctly into position, prevent it from
shifting.
(4) Bring the soldering iron tip close to the part
contact without actually touching it. Melt thin
(0.3mm)
solder
between
the
tip
and
part
so
that
it
flows into the part contact.
(5) Check work quality with a magnifier.

3-4. Chip Tantalum Capacitors and Chip
Filters
3-4-1. Kind of the Part
The kind of chip tantalum capacitors and chip filters
are as follows:
(1) Chip Inductors
(2) Chip Tantalum Capacitors
(3) Chip Tantalum Electrolytic Capacitors
(4) Chip Aluminum Electrolytic Capacitors
(5) Chip Transformers
(6) Chip Filters
3-4-2. Removing the Part
(1) Using special desoldering iron:
(D Select soldering tip according to part size.
@ Bring the tip into contact with the soldered points.
When the solder melts, remove the part.
@Remove the old solder with desoldering wire.
(1) Using two soldering irons:
(D Use small flat-blade tips.
(Heat both ends of the part simultaneously.
@ When the solder melts, grasp and remove the part
with the soldering iron tips.
@ Remove the old solder with desoldering wire.
W..
\b=
Awe
wy
!
NE
Wwe
3-4-3. Installing the Part
(1) Clean the area where the new part is to be
mounted.
(2) Apply flux
(3) In part correctly into position, prevent it from
shifting.
(4) Use sharp soldering iron tip. Bring close to the
Part contact without actually touching it. Melt thin
solder between the tip and part so that if flows
into the part contact.
(5) Check work quality with a magnifier.
FIG. 5
MM-77
3-5. Chip VRs, Chip Trimmer Capacitors,
Diodes and Tr.
3-5-1. Kind of the Part
The kind of the part is as follows:
(1) Chip VRs
(2) Chip Trimmer Capacitors
(3) Diode
(4) Transistors
3-5-2. Removing the Part
(1) Using two soldering irons:
@ Use small flat-blade tips.
@ Heat the leads of the part simultaneously.
@) When the solder melts, grasp and remove the part
with the soldering iron tips.
@ Remove the old solder with desoldering wire.
3-5-3. Installing the Part
Oy
YS
/
Y
FIG. 6
(1) Clean the area where the new part is to be
mounted.
(2) Apply flux
(3) Set part correctly into position, prevent it from
shifting.
(4) Use sharp soldering iron tip. Bring close to the
part contact without actually touching it. Melt thin
solder between the tip and part so that it flows
into the part contact.
3-6. Chip ICs
3-6-1. The kind of the Chip ICs
The kind of the chip ICs are as follows:
(1) SOP (Small Outline Package) IC
(2) SSOP (Shrink Small Outline Package) IC
(3) VSOP (Very Small Outline Package) IC
(4) QFP (Quad Fiat Package) IC
(5) VOFP (Very Quad Flat Package) IC
(6) PLCC (Plastic Leaded Chip Carrier) IC
(7) TSOP (Thin Small Outline Package) IC

3-6-2. Removing the Part
(1) Using special desoldering iron:
Select the tip according to the size and shape of
the IC.
@ Thin" the tip with a small amount of the IC leads.
@) Set the tip squarely over the IC leads.
@ When the solder melts, carefully twist the iron.
©) Raise and remove the IC.
(2) Using shaped airblower unit:
@ Select the correct nozzle.
@) Select the temperature and airblow (suggested:
temperature: 7, airblow: 4)
@) Engage the IC removing tool.
@ Use the airblow to preheat the IC for about 5
seconds, then heat with the nozzle until the IC
remover lifts the part from the board.
=
ea
|
FIG. 7
MM-77
3-6-3. Installing the Part
(1)
Use
desoldering
wire
to
remove
the
previous
older.
(2) Clean the location.
(3) Apply flux.
(4) Position the IC and solder two pins at opposite
sides.
(5)
Use
a
sharp
tipped
soldering
iron
and
carefully
solder
each
pin.
(After
graining
experience,
a
thicke
tip
can
be
used
for
better
work
efficiency.)
(6)
Remove
any
solder
bridges
with
desoldering
wire.
(7) Inspect the work with a magnifier.