Seiko ASTRON GPS SOLAR 3x62 Assembly instructions

3X62
HANDY MANUAL
Printed in Japan
BSN3X62-A2303
<
English
>

1 2
For details, please read the
“3X62 Complete User Guide”
(https://www.seikowatches.com/global-en/
customerservice/instruction/).
Thank you very much for
choosing a SEIKO watch.
For proper and safe use of
your SEIKO watch,
please read carefully the
instructions in this
booklet before using it.
Keep this manual handy
for easy reference.
Length adjustment service for metallic bands is
available at the retailer from whom the watch was
purchased. If you cannot have your watch repaired
by the retailer from whom the watch was purchased
because you received the watch as a gift, or you moved
to a distant place, please contact SEIKO CUSTOMER
SERVICE CENTER.The service may also be available
on a chargeable basis at other retailers, however, some
retailers may not undertake the service.
If your watch has a protective film for preventing
scratches, make sure to peel it off before using the
watch. If the watch is used with the film on it, dirt,
sweat, dust, or moisture may be attached to the film
and may cause rust.
CONTENTS
1. Features��������������� 3
2. Names of the parts ���������5
3. Check the charging status ������7
4. Time zone �������������� 9
5. List of time differences around the
world (for reference) �������� 11
6. To adjust the time zone and time by
GPS signal reception (time zone
adjustment) ������������ 13
7. To adjust only the time by GPS
signal reception (manual time
adjustment) ������������ 15
8.
Setting the destination time zone
while in flight, etc. (manual time
difference setting), and setting/
resetting DST (daylight saving time
or “summer time”) ��������� 17
9. When boarding (in-flight mode ( )) � 19
10. Leap second (Automatic leap second
reception function) �������� 21
11. Reception result display ������ 23
12. How to check when the time zone
information was configured for your
watch ��������������� 25

3 4
GPS signal reception
Features
This is a GPS solar watch.
This watch has the following features.
Standard Charging Time
The time on the watch can be adjusted
to the current time with just one button
operation*, anywhere in the world.
 DST (daylight saving time or “summer time”) is
set manually
This watch quickly
adjusts the time by
receiving GPS signals
from GPS satellites.
This watch responds to
all the time zones around
the world.
When the region or time zone where the watch
is used is changed, please carry out operation
of “time zone adjustment.”
1
Charge the watch using the times below as a guide.
GPS signal reception consumes considerable energy. It is necessary to charge the watch by exposing it to
light frequently so that the indicator hand points to the “middle” or “full” position. (If the energy level
is “low”, reception will not begin even if GPS signal reception is operated.)
The figures of “Time required for charging the watch to start moving at one- second intervals” are estimations of time required to charge the stopped
watch by exposing it to light until it moves at steady one-second intervals. Even if the watch is partially charged for a shorter period, the watch will
resume one-second- interval movement. However, it may shortly return to two-second-interval movement. Use the charging time in this column as a
rough guide for sufficient charging time.
The required charging time slightly varies depending on the model.
When the energy
stored in the watch
runs out completely,
it takes time to fully
charge the watch,
so please keep in
mind to charge the
watch regularly.
Solar charging Function
This watch operates by solar charging.
Expose the dial to light to charge the watch.
The watch will operate for about 6 months
on a full charge.
Automatic time adjustment function
This watch automatically adjusts the time in
accordance with action patterns during use.
When the watch has sensed suf ficient brightness under
an open sky, it automatically receives GPS signals
from GPS satellites. This function enables the watch to
automatically adjust
the time precisely
even while you are
using the watch.
This watch is
unable to receive
GPS signals when
the energy stored
in the watch is
low.

Unlike navigation equipment, this GPS solar watch is not designed to constantly receive GPS signals from GPS satellites without any operation.
This watch receives GPS signals only in the time zone adjustment mode, automatic or manual time adjustment mode.
Illumination
lx (LUX) Light source Condition (Example)
From the state where the watch is stopped
(not charged)
In the state where the hand
moves (the watch is charged)
To fully charged To one-second interval
movement is secured To move for one day
700 Fluorescent light General offices
－ －
3.5 hours
3,000 Fluorescent light 30W 20 cm 250 hours 9.5 hours 1 hours
10,000 Sunlight
Fluorescent light
Cloudy day
30W 5 cm 75 hours 3 hours 15 minutes
100,000 Sunlight Sunny day (Under the direct sunlight
on a summer day) 30 hours 1.5 hours 10 minutes
1. Features

5 6
Names of the parts
2

The orientation and design of the display may vary
depending on the model.
2. Names of the parts
Crown
Minute hand
Date
Button A
Hour hand
Seconds hand
Indicator hand
Button B

7 8
3
Check the charging status
3. Check the charging status
Indicator
display
Movement of
second hand Charging status Solution
1-second
interval
movement
low
The watch
is unable to
receive GPS
signals, but
has energy
to operate.
Charge the watch at least until
the indicator hand points to the
level position so that the watch is
able to receive GPS signals.
2-second
interval
movement
The watch
is unable to
receive GPS
signals, and
does not
have energy
to operate.
(The energy
depletion
forewarning
function is
activated.
Continue to charge the watch
at least until the indicator hand
points to the level position
so that the watch is able to
continuously operate and receive
GPS signals.
5-second
interval
movement
The charging status is
not displayed for the
in-flight mode
().
Reset the in-flight mode ( ).
When the indicator hand points
to “low,” charge the watch
following the above.
Indicator
display
Charging
status Solution
full Reception is
allowed.
middle
Reception is
allowed, but
keep in mind
to charge the
watch.
The indicator hand position shows whether this watch is able or unable to receive GPS signals.
In addition, for the low charging state, the movement of the second hand shows the energy depletion state in
further detail.
Reception is
allowed
Reception is
not allowed

910
Time zone
4
Time zone
Based on Coordinated Universal Time (UTC), the
standard time commonly used is adopted by countries
and regions around the world.
Standard time is determined by nations and regions,
with “time zone” used to refer to the whole of a
region that uses the same standard time. At present,
the globe is divided into 38 time zones (as of October
2022).
DST (Daylight SavingTime)
Depending on the area, DST (Daylight SavingTime) is
individually set.
Daylight SavingTime means summer time, which is a
system to lengthen daylight time by advancing 1 hour
when daylight time is long in summer.
The adoption and duration of daylight saving time
vary depending on the country.
DST (daylight saving time or “summer time”) in each region may be
changed by countries and regions.
Coordinated Universal Time
(UTC)
UTC is the universal standard time coordinated
through an international agreement.This is used
as the official time for recording time around the
world.The time obtained by adding a leap second
to the “International AtomicTime (TAI)” determined
based on the atomic clock around the world and
coordinated in order to compensate for deviations
from universal time (UT) which is astronomically
determined is the UTC.
4. Time zone

11 12
List of time differences around the world (for reference)
5
This is a list of time differences around the world.
When performing manual time difference setting
(selection), refer to the crown rotation direction.
DST (Daylight SavingTime) has been adopted in countries marked with a ★.
In the Lord Howe Island time zone in Australia with a mark, the time is
advanced by 30 minutes while DST (Daylight SavingTime) is in effect.
Representative city names…
All global time zones
Time difference from UTC:
+14 hours ~ –12 hours
Information about time differences among regions (time zones) and the
implementation of DST (daylight saving time or “summer time”) is as
of October 2022.
5. List of time differences around the world (for
reference)
List of time differences around the world
(for reference)
City name UTC
± hours
Beijing +8
Eucla +8.75
Tokyo +9
★Adelaide +9.5
★Sydney +10
☆
Lord Howe Island +10.5
Nouméa + 11
★Wellington +12
★
Chatham Islands
+12.75
Nuku’alofa +13
Kiritimati +14
Baker Island –12
Midway islands – 11
City name UTC
± hours
★London 0
★Paris/★Berlin +1
Cairo +2
Jeddah +3
Tehran +3.5
Dubai +4
Kabul +4.5
Karachi +5
Delhi +5.5
Kathmandu +5.75
Dhaka +6
Yangon +6.5
Bangkok +7
City name UTC
± hours
Honolulu –10
Marquesas Islands –9.5
★Anchorage –9
★Los Angeles –8
★Denver –7
★Chicago –6
★NewYork –5
Santo Domingo –4
★St. John’s –3.5
Rio de Janeiro –3
Fernando de
Noronha –2
★Azores –1
Operation of the crown when manually setting the
time difference
Turning the crown to
the right moves the time
forward.
Turning the crown to
the left moves the time
backward.

13 14
Go to a place where
GPS signals can be
easily received
1
Move to the outdoors
under an open sky
with good visibility.
The time zone where you are is localized to adjust the watch to the precise current time by just one
button operation anywhere in the world.
DST (daylight saving time or “summer time”) is set manually
6
How to adjust the time zone
Time zone adjustment
Precautions on time zone adjustment
When time zone correction is performed near a border between time zones, the time for the neighboring time difference (time
zone) may be displayed.
In some areas the boundaries observed by the watch may not exactly correlate to the actual time zone markers on the land.
This does not indicate a malfunction. In this case, please set (select) the time difference manually.
When the time zone is adjusted while traveling on land, avoid time zone boundaries to carry out time zone adjustment in the
representative cities in the time zone whenever possible.
When using the watch near a time zone border, be sure to confirm the time and set (select) the time difference manually as necessary.
6. To adjust the time zone and time by GPS signal
reception (time zone adjustment)
To adjust the time zone and time by GPS signal reception (time zone
adjustment)
Continue to press Button B (3 seconds),
and then release it when the second hand
moves to the 30-second position
2 3
Direct the watch face upward and
wait
<
Display during reception (= satellites
acquisition status)
>
The second hand indicates ease of
receiving (= number of GPS satellites
from which GPS signals are received).
Even when the hand
points to 4 units or
more, reception may
not be allowed.

Please note that it may be difficult to receive
GPS signals while you are in motion.
To cancel the
reception, press
Button B.
When the second hand
points to “Y” or “N,”
reception is completed
4
The buttons cannot be
operated while the hour and
minute hands, indicator hand
and date are moving.
The reception result is
displayed for 5 seconds.
If reception is successful,
the time and date are
adjusted.
The settings for the time
zone are reflected in the
time that appears.
When the second hand has reached
the 30-second position, reception is
started.
The indicator hand points to “4+.”
 While the indicator hand points to “low” or ,
reception is not started even with operation
for reception.
When the hand points to “low,” charge the
watch by expose to light.
When the hand points to , reset the in-
flight mode ( ).
It takes a maximum
of 2 minutes to
complete reception.
It depends on the
receiving conditions.
Second hand
position
25-second
Number of
satellites
5 units
 The larger the number
of acquired satellites
there are, the easier
it is to receive GPS
signals.
Press for
3 seconds
May
receive
E
a
s
y
t
o
r
e
c
e
i
v
e
C
a
n
n
o
t
r
e
c
e
i
v
e
・
・
・
・
・
・
3 units
4 units
5 units
6 units
2 units
0 units
BPC
J
J
Y
Reception
result
display
Y: Successful
(8-second
position)
N: Failed
(52-second
position)
Display
State Use the watch
as it is.
Press
Button B

15 16
Manual time adjustment
How to manually adjust the time
The watch can be set to the correct current time for the set (selected) time difference.
(The time zone will not be changed.)
7
7. To adjust only the time by GPS signal reception
(manual time adjustment)
To adjust only the time by GPS signal reception (manual time
adjustment)
When the second hand points
to “Y” or “N,” reception is
completed
4
The reception result is
displayed for 5 seconds.
If reception is successful, the
time and date are adjusted.
3Direct the watch face upward
and wait
Continue to press Button A (3 seconds), and
then release it when the second hand moves
to the 0-second position
2
When the second hand has reached the
0-second position, reception is started.
The indicator hand points to “1.”
To acquire only time information,
the number of satellites necessary
for reception is one.
Number of
acquired
satellites
1 0
Display
State Easy to
receive
Cannot
receive
To cancel the reception, press
Button B.
Check that the reception is
successful after the watch
returns to the time display
mode.
When the time is not correct
even if “Y” is displayed, the
time zone and DST (daylight
saving time or “summer
time”) may not correspond
to the region where you are.
Manually set the time zone
setting as necessary.
The buttons cannot be operated
while the hour and minute hands,
indicator hand and date are
moving.
Reception
result
display
Y: Successful
(8-second
position)
N: Failed
(52-second
position)
Display
State
Use the
watch as it is.
While the indicator hand points to “low” or ,
reception is not started even with operation for
reception.
When the hand points to “low,” charge the
watch by exposing it to light.
When the hand points to , reset the in-flight
mode ( ).
It takes up to one
minute to complete
reception.
The reception time
depends on the
reception conditions.
<
Display during reception
(= satellites acquisition status)
>
The second hand indicates ease
of receiving (= number of GPS
satellites from which GPS signals
are received).
Press
Button B
Press for
3 seconds
Go to a place where
GPS signals can be
easily received
Move to the
outdoors under
an open sky
with good
visibility.
1

17 18
When time zone adjustment cannot be performed, the time difference can be set (selected) manually.
Using “List of time differences around the world (for reference)” P.11 as a guide, the watch can be matched to the time and
date of your location by setting the time difference (including the date).
Pull out the crown to the first
click
1
The seconds hand will
move to the 0-second
position.
Push the crown back in
4
The seconds hand returns
to the time display mode.
The buttons cannot be
operated while the hour,
minute, and seconds hands
and the date are moving.
How to perform manual time difference setting (selection)
8
About manual time difference setting (selection)
8. Setting the destination time zone while in flight, etc.
(manual time difference setting), and setting/resetting
DST (daylight saving time or “summer time”)
Setting the destination time zone while in flight, etc. (manual time difference
setting), and setting/resetting DST (daylight saving time or “summer time”)
3Pull out the crown to the
second click
Turn the crown to set the watch
to the time at the destination
2
Each turn of the crown changes
the time in 1-hour increments.
When the time has been set
in 1-hour increments, go to
operation 4.
When setting the time in
1-hour increments does not
set the correct time, continue
with setting the time in 15-
minute increments.
Take note of which way you
turn the crown.
By making adjustments 4
times, an adjustment of 1 hour
can be made.
Take note of which way you
turn the crown.

To set the watch to the time at the
destination, the time and date must
be set. If you turn the crown in the
wrong direction, change direction
and reset the date and time.
A date up to about 2 weeks later
(or earlier) can be displayed.
Note that changing the date
too far will result in a date two
weeks earlier (or later).
Turning the
crown to the
right moves
the time 1
hour forward.
Turning the
crown to the
left moves the
time 1 hour
backward.
Turning the
crown to the
right moves
the time
15 minutes
forward.
Turning the
crown to the
left moves
the time
15 minutes
backward.
012
Pull out
to the first
click
012
Push
back in

19 20
9When boarding (in-flight mode ( ))
Set to the in-flight mode ( ). In-flight mode
( )
9. When boarding (in-flight mode ( ))
Press for
3 seconds
Reset the in-flight mode ( ).
Turn off the in-flight mode when leaving an airplane, etc.
If it is not turned off, the watch will not be able to
receive GPS signals.
Carry out operation 1to 3.
When the indicator hand points to “the charging status”
in the figure at the right, the in- flight mode ( ) is reset.
<
In-flight mode ( )
>
The indicator hand points
to .
When the in-flight mode ( )
is reset, the indicator hand
indicates the charging status.
Set to the in-flight mode
() where the reception
may influence operation of
other electronics devices
in an airplane, etc.
In the in-flight mode ( ),
the GPS signal reception
(time zone adjustment,
manual time adjustment,
and automatic time
adjustment) does not
work.
The display when the charging
status is “full”
Pull out the crown to the first click
1
The seconds hand will move
to the 0-second position.
Push the crown back in
3
The seconds hand will
return to the time display
mode.
When the in-flight mode
() is set, the indicator
hand does not indicate the
charging status.
Continue to press Button B
(3seconds)
2
The indicator hand displays
the in-flight mode ( ).
When continuously pressing
Button B again, the in-flight
mode ( ) is reset and the
indicator hand indicates the
charging status.
Take note that turning the
crown at this time will perform
manual time difference setting.
Pull out
to the first
click
012012
Push
back in

21 22
10
Leap second
The leap second is to compensate for deviations
from the universal time (UT) which is astronomically
determined and the “International AtomicTime (TAI).
“1 second” may be added (deleted) once a year or every
few years.
Automatic leap second reception
function
A leap second is automatically added by receiving “leap
second data” from GPS signals at the time of leap
second addition (delete).
“Leap second data” includes information about future leap second
addition and current leap second data.
10. Leap second (Automatic leap second reception
function)
Leap second (Automatic leap second reception function)
When GPS signals are received under the following
conditions, the leap second data reception is also
started.
• GPS signals are received after the system reset
• GPS signals have not been received for a long time
• Leap second data reception has failed
(Leap second data reception is performed again during the next
GPS signal reception. It is repeated until the leap second data
reception is successful.)
Receiving Leap Second Data
When the GPS signal reception
(automatic time adjustment,
manual time adjustment,
or time zone adjustment) is
performed on or after December
1st and June 1st, the indicator
hand may display as shown at
the right.
When the leap second data reception is completed, the
indicator hand returns to display the charging status.
Use the watch as it is.
The leap second data reception is performed every half a year
regardless of leap second addition.
It takes up to 18 minutes to receive the leap second data.
Receiving the leap second data

23 24
11
Reception result display
The results of GPS reception (time adjustment or time zone adjustment) and leap second data reception (successful /
failed) are displayed for 5 seconds.
Check whether reception was successful
11. Reception result display
Press
and then
release
Press
and then
release
3Press Button A and then release it while the result of the reception is
displayed (for 5 seconds) in step 2
Second hand: Reception result
(successful / failed)
The second hand and
indicator hand display the
reception result.
The second hand displays
the result of the GPS signal
reception (time adjustment
or time zone adjustment).
The indicator hand points
to “1” or “4+” which
shows “time adjustment”
or “time zone adjustment.”
The second hand displays the
result of the leap second data
reception (successful / failed).
The indicator hand displays
“LEAP SEC.” of the leap
second data reception.
Press Button A and then
release it
The result of the reception is
displayed
2
Result Successful Failed
Display
Position Y 8-second
position
N 52-second
position
When the leap second data
reception result isY (successful)
• The leap second data reception was
successful.
Use the watch as it is.
When the leap second data
reception result is N (failed)
• The leap second data reception,
periodically performed, has not been
successful.
It will be performed automatically
with the next GPS signal reception
(automatic time adjustment, manual
time adjustment or time zone
adjustment).
Use the watch as it is.

The leap second data is received on
or after December 1st and June 1st.
Even when the leap second data
reception has not been successful,
the time is correct until the leap
second data is added (deleted).
After 5 seconds have
elapsed, or when Button
B is pressed, the watch
returns to the time display
mode.
The indicator hand points to
“4+” as a result of time zone
adjustment.
After 5 seconds have elapsed
or when Button B is pressed,
the watch returns to the time
display mode.
Result Successful Failed
Display
Position Y 8-second
position
N 52-second
position
Second hand: Reception result
(successful / failed)
1
When Button A is kept
pressed, the watch
enters the Manual time
adjustment operation.

3
3
X
X
6
6
2
2
-
-
0
0
0
0
0
0
0
0
25 26
12
The case back shows the caliber-case
number of your watch.
By referring to caliber-case number shown on the case back, you will be
able to determine when the time zone data was configured.
For more details, refer to the URL below.
https://www.seikowatches.com/global-en/customerservice/
knowledge/gpstimezonedatainfo/
In a region where the time zone has changed after time zone information
was set on your watch, the correct time will not be displayed even if
time zone adjustment is performed through GPS radio reception. Please
perform the following operations to display the proper time.
<To set the time on the product in a region in which the
time zone has changed>
1. Select the current time in the region, using the manual time difference
setting (selection).
If DST (daylight saving time or “summer time”) is in effect, select a
time that takes that into account.
→For details, please refer to “8. Setting the destination time zone
while in flight, etc. (manual time difference setting), and setting/
resetting DST (daylight saving time or “summer time”)” P.17
2. Next, adjust the time by manual time adjustment.
→For details, please refer to “7. To adjust only the time by GPS signal
reception (manual time adjustment)” P.15
3. When using the watch within the same time zone, the correct time will
be displayed after automatic (GPS) or manual time adjustments.
4. When moving from a region where the official time zone has changed
to a different time zone, then back to the region where the official
time zone has changed, carry out the same operations from 1. - 3. as
indicated above to display the correct time in the region where the
official time zone has changed.
Caliber/case
number
The number
to identify the
watch type
How to check when the time zone information was configured for
your watch
Display may vary depending on the model.
12. How to check when the time zone information was
configured for your watch

27
SPECIFICATIONS
The specifications are subject to change without prior notice due to
product improvements.
Product : GPS solar watch
Model : 3X62
This product is in compliance with the essential
requirements and other relevant provisions of the RE
Directive (2014/53/EU)& RoHS Directive(2011/65/EU).
https://www.seikowatches.com/global-en/products/
declaration-conformity
This product is in compliance with the essential
requirements and other relevant provisions of Radio
Equipment Regulations 2017 & The Restriction of the
Use of Certain Hazardous Substances in Electrical and
Electronic Equipment Regulations 2012.
https://www.seikowatches.com/global-en/products/
declaration-conformity
SEIKO WATCH CORPORATION
https://www.seikowatches.com/
1. Basic function ………………… Basic watch (hour, minute, and
seconds hands), date display,
indicator function
2. Frequency of crystal oscillator … 32,768 Hz (Hz = Hertz ... Cycles per
second)
3. Loss/gain (monthly rate) …… Loss / gain ±15 seconds on a
monthly rate (When the watch is
used without an automatic time
setting by receiving GPS signal
and when it is worn on the wrist
within a normal temperature range
between 5°C and 35°C (41ºF and
95ºF)).
4.
Operational temperature range … Between −10°C and +60°C (14ºF
and 140ºF)
5. Driving system ……………… Step motor type: Basic watch
(hour, minute, and seconds
hands), date, indicator hand
6. Power source ………………… Secondary battery, 1 piece
7. Duration of operation ……… About 6 months (on a full charge,
without power save function)

If the Power Save is activated
after it is fully charged, the
watch continues to run for
approximately 2 years at
maximum.
8.
GPS signal reception function … Time zone adjustment, manual
time adjustment, automatic time
adjustment

Between reception and the next
reception, the watch operates
with the above quartz precision.
9. IC (Integrated Circuit) ……… Oscillator, frequency divider and
driving circuit C-MOSIC, 4 pieces