Junghans J820.3 User manual

Chronometerwerk
Chronometer movement
J820.3
J U N G H A N S – D I E D E U T S C H E U H R

1514
JUNGHANS – THE GERMAN WAT C H
Many congratulations on your purchase of a timepiece from
Junghans.
What began in 1861 with the founding of the firm in Schramberg
quickly developed into one of the most fascinating success stories
of the German watchmaking industry. While since that time the
demands made of watches may have changed, the Junghans
philosophy has always remained the same. Innovative flair and the
constant pursuit of precision right down to the smallest detail
define how the company works and thinks. You can see and sense
this in every watch that carries the Junghans name. For as diverse
as the Junghans range may be, it pursues one single goal: to
combine traditional craftsmanship with cutting-edge watch
technology and exciting design. That makes every watch with the
Junghans star unique.
We hope you will enjoy this very special time-keeping instrument.
Yours,
Uhrenfabrik Junghans GmbH & Co. KG
ENGLISH

1716
Contents Page
Instructions for use 17
General information 22
Instructions for use
Important note:
Do not make any changes to the date between 08:00 p.m. and 02:00
a.m., as the date is automatically advanced by the movement during
this period and you could damage the date advance mechanism.
Chronometer test
Your watch is subjected to chronometer testing, guaranteeing you the
highest precision and reliability as a consequence. The strict criteria of
the chronometer test as per DIN 8319-1 stipulate a 15-day test at differ-
ent temperatures in the five positions "crown left", "crown above",
"crown below, "dial above" and "dial below". The test is documented in
the form of a chronometer certificate.

18 1918
Winding up the watch
With the winder in position A, you can wind up the automatic move-
ment manually. At least 2 to 3 rotations of the winder are needed to
start the movement. It is better to wind it up completely. It is fully
wound up after c. 43 rotations of the winder, as then the maximum
accuracy and its power reserve (even after the watch is put down) will
last for the maximum period. After you have set your watch, you should
wear it, so that the automatic winding system (via rotor movement)
keeps it constantly operational.
Setting the time
Pull the winder into position C. That stops the watch movement.
To set your watch accurately to the second, it is best to stop the
movement as the second hand is passing the figure 60. You can now
position the minute hand precisely in line with the relevant minute
marker and set the desired time. Press the winder back into position A
to start the second hand.
Features and functions
Calibre J820.3
25
1
2
3
4
5
A B C
1 Hour hand
2 Second hand
3 Minute hand
4 Winder
5 Date display

2120
Setting the date
Pull the winder into position B. You can now set the date by turning it
to the right. Do not make any changes to the date between 08:00 p.m.
and 02:00 a.m. as the date is automatically advanced by the move-
ment during this period and you could damage the date advance
mechanism. If the month has less than 31 days, set the date manually
to the first day of the following month.
Technical information
Certified chronometer movement with display for date
Calibre J820.3
Bi-directional winding
21 jewels
28,800 semi-vibrations per hour
42 hour power reserve
Anti-magnetic to DIN 8309
Shockproof: Nivachoc
Balance: Gold-plated Glucydur
Impermeability
Marking Instructions for use
Washing,
rain,
splashes Shower Bath Swimming
Diving
without
equipment
No mark No No No No No
3 ATM Yes No No No No
5 ATM Yes No Yes No No
10 ATM Yes Yes Yes Yes No
The designation ”3 – 10 ATM” only applies to brand new watches.
External influences can affect water resistance. Please have your watch
checked regularly.

22 23
General information
External influences can affect the watch’s waterproof qualities, which
may let in moisture. We therefore recommend that you have your
watch regularly inspected by your Junghans specialist. Other servicing
tasks or wrist strap repairs should also be done by your Junghans
specialist. Your watch is fitted with a quality wrist strap that has under-
gone multiple inspections in our factory. If, however, you decide to
change the strap, please fit a new one of the same quality, preferably an
original Junghans wrist strap. Watch and wrist strap can be cleaned
with a dry or slightly moistened cloth.
NB: Do not use che mical cleaners (e.g. benzine or paint thinners). These
may harm the surface.

42.712-0596 / XXXXXXX / 0415 J820.3
Uhrenfabrik Junghans GmbH &Co. KG
Postfach100 · D-78701 Schramberg
www.junghans.de · [e-mail]