ST1903 Mechanical movement
User Manual Instructions
Thanks for using seagull ST1902/ST1903 movement. Please read the following
instructions carefully before use
：
FUNCTIONS
：
Regulator of Center hour hand, minute hand, second hand. 3-point minute
counting instructions, 30 points / circle; 6 o'clock hour hand instructions (synchronized
with the center hour hand); 9 o'clock small seconds hand, hand winding. (1903
movement 6 o'clock hour hand, 24 hours / circle, others are same with the 1902
movement).
SPECIFICATION
：
Calibre diameter
：
Φ
31.3mm; Thickness
：
H6.25mm; 21600vibrations per hour
；
22 Jewels
ADJUSTMENTS:
Crown position “1”
，
manual winding.
Crown position “2”
，
corrector.
Press
“
M
”
button
，
timing begins;
Press
“
M
”
button again
，
timing stops;
Press
“
N
”
button
，
return to zero.
ASSEMBLY
:
1. Assemble dials and hand:
2. Press M timing ON/OFF button to stop counting seconds; then press N button, Counting
back to zero.
3. Put the movement on the special base and remove the craft hand. (Use a special tool to
pull up the craft hand vertically to avoid bent or broken)
4. Unscrew the two fixing screws on the movement and tighten the fixing screws after
installing the dial.
5. Gently pull the crown to the 2nd gear position, install 6 o'clock 12o'clock small seconds,
aim at 6 o'clock "12" characters.
6. Install the 3 o'clock chrono hand and align the 3 o'clock "30" character.
7. Install the center hour, the minute hand; Do not deviate when the hour/minute hand
points to"12" characters.
8. Install Counting seconds (Center long second hand). Install hands when align the 12
o'clock character. Error <0.1 seconds
9. Install Small seconds of 9 o’clock.
INSPECTION
：
1. Each hands should be parallel to the dial with average gap. Do not deviate the hour hand
and minute hand of 12 o’clock.
2.
Seconds timing function:(1)press M button, timing begins;(2)press M button again, timing
stops;(3)press N button, return to zero.
（
Center seconds counter zero, pointing to "12"
characters, 3 o'clock minute hand aimed at "30" characters.) Confirm that the countdown /
zero return function are reliable.
LOAD IN THE CASE
Clean dials and cases, load the movement into the case without any dirt. Put two clamps into slot, locking
screws and screwing the back case. (Put the holder into the case straight if no clamps)
ATTENTION: Do not press the position “4” N button to return zero when the
Chronograph second hand moves. You should press position “2” M
button to stop timing then press position “4” to return zero. Timing range 0-30 minutes. The hour
hand of 6 o’clock should be same as the center hour hand without timing function.
