Altichron (Movement: J280/J290)
This operation guide covers altitude measurement/calibration, compass measurement/calibration and FAQ about them. Refer to the instruction manual (J280/J290) for usage of other functions.
J280 is used for illustrations and movies for explanation below.
Measuring altitude
<Caution>
- Use the measuring result only as a reference.
- Use a commercial specialized device when highly accurate measurement is required.
- Confirm the power reserve is in level "2" or higher before measurement.
- Push the crown in to position "0".
- Press button B.
Altitude is indicated.
It may take a moment to indicate altitude.
Wait until movement of the hands stop.If you press button A while indicating altitude, the 100 m (1000 ft) hand temporarily indicates compass direction.
Press button A to return to altitude indication. - Press button B to finish measurement.
How to read altitude indication
Altitude is indicated by the 3 hands, the 1000 m (10000 ft), 100 m (1000 ft) and 2.5 m (25 ft) hands.
The hands indicate "2137.5 m" on the example below.
How to read the 1000 m (10000 ft) hand indication
| Indication range | J280: Thousands place (1000 m to 10000 m) |
|---|---|
| J290: Ten thousands place (10000 ft to 30000 ft) |
The hand points "0" when measured altitude is lower than 1000 m (10000 ft).
On the example in the left, the measured altitude is indicated as 2000 m level.
How to read the 100 m (1000 ft) hand indication
| Indication range | J280: Hundreds place including minus indication (-300 m to +900 m) |
|---|---|
| J290: Thousands place including minus indication (-1000 ft to +9000 ft) |
The hand points "0" when measured altitude is 0m (0 ft) or higher and lower than 100 m (1000 ft).
On the example in the left, the measured altitude is indicated as 100 m level.
How to read the 2.5 m (25 ft) hand indication
| Indication range | J280: Last 2 places (-97.5 m to +97.5 m by 2.5 m) |
|---|---|
| J290: Last 3 places (-975 ft to 975 ft by 25 ft) |
The 100 m (1000 ft) hand points minus indication when measured altitude is lower than 0 m (0 ft).
In this case, use figures in parentheses to read the 2.5 m (25 ft) hand.
On the example in the left, the measured altitude is indicated as 37.5 m (or -62.5 m).
Measured altitude is indicated in 5.0-m height when it is more than 6000 m.
When the measured altitude is out of the indication range
The altitude indication range of this watch is as follows:
| Indication range | J280: -300 m to +10000 m |
|---|---|
| J290: -1000 ft to 32000 ft |
When the measured altitude cannot be indicated, the 1000 m (10000 ft) hand points the arrow (3 o'clock position) and stops.
Calibrating altitude indication
You can correct altitude measured by the watch when you know the actual height from a map, sign or other sources for future measurement.
You can calibrate the value in the range of -1000 m (-3000 ft) to +1000 m (+3000 ft) of currently measured altitude.
The corrected value can be reset (initialized).
- Press button B.
The measured altitude is indicated.
It may take a moment to indicate altitude.
Wait until movement of the hands stop. - Press and hold button B for 3 seconds or more.
The 1000 m (10000 ft) hand points "+" and calibration of altitude indication becomes available.
- Press button B to choose + or -.
+ – Choose this when the actual altitude is higher than the measured one. Choose this when the actual altitude is lower than the measured one. 
Each time you press the button, choice of "+" and "‒" changes alternately.
Repeat steps 3 and 4 to control the altitude value after calibration.
- Press button A to correct the indication to the actual altitude.
Move the 100 m (1000 ft) and 2.5 m (25 ft) hands to indicate an approximate value of the altitude.
Indication keeps changing while you are pressing and holding the button.
- Press and hold button B for 3 seconds or more.
The corrected altitude is set as the current one and the hands return to measured altitude indication.
The corrected altitude is set as the current one and the hands return to measured altitude indication in 1 minute without any operation.
- Press button B to finish the procedure.
Press button A and button B at the same time to reset the calibration value.
Using the compass
<Caution>
- Use the compass direction result only as a reference.
- Use a commercial specialized device when highly accurate measurement is required.
- Confirm the power reserve is in level "2" or higher before measurement.
- Press button A while keeping the watch's dial level.
Compass function starts.
It may take a moment to indicate the compass direction.
Wait until movement of the hands stop.Keep the watch as level and still as possible until compass direction finishes.
- After finishing measurement, press button A to turn off the function.
Compass indication ends in 30 seconds without pressing the button.
<Caution>
Compass direction result may become significantly inaccurate near things which generate strong magnetic fields.
Confirm there are no things or places such as following ones before using the compass.
- High-tension electrical lines, railway overhead wires or airport
- Inside a car or electric train
- Cellular phones, electric equipment or office appliances
- Magnets
It is recommended to calibrate frequently for better compass direction.
Calibrating compass indication
About compass correction
This watch measures earth magnetism directly with the built-in magnetic sensor for compass indication.
Earth magnetism measurement is apt to be easily affected by environmental conditions near a magnet or thing emitting strong electromagnetic waves.
In addition, generally, the north which a compass points to (magnetic north) is different from that on a map (true north). You can determine the true north through the compass function by calibration and adjustment of the watch.
You can use 2 methods to calibrate the compass of this watch: 2 point correction and declination correction.
The corrected value can be reset (initialized).
| 2 point correction | Use it when temperature drastically changed or the watch itself may be magnetized. (The compass hand may look attracted to a certain direction when the watch is magnetized.) 2 point correction is more effective if you do it before using the compass. |
|---|---|
| Declination correction | A correction method to adjust the compass of the watch to indicate the north on a map by setting the declination value of the location where you wants to use the compass on the watch previously. |
Executing 2 point correction
When executing 2 point correction, you must turn the watch just 180º while keeping it level.
Take enough care of surrounding conditions before starting correction.
<Caution>
Confirm you are not near an item with strong magnetism (electric equipment, magnets, etc.) before starting correction.
- Press button A.
Compass function starts.
It may take a moment to indicate the compass direction.
Wait until movement of the hands stop. - Press and hold button A for 3 seconds or more.
The compass hand points the 3 o'clock position.
- Press button B.
The first surrounding environment data is stored and the compass hand turns 180º to point the 9 o'clock position.
- Turn the watch by 180º.
- Press button B.
The second surrounding environment data is stored and the compass hand points the 12 o'clock position.
2 point correction completes and compass function starts.If the compass hand returns to the 3 o'clock position, try again from step 3.
Press and hold button A for 3 seconds or more to cancel the correction.
When canceled, no correction is executed and the previous correction result remains effective. - Press button A to finish the procedure.
Pressing the buttons A and B at the same time before finishing step 5 resets the values of 2 point correction and declination correction and the watch returns to compass function.
Executing declination correction
- Press button A.
Compass function starts.
It may take a moment to indicate the compass direction.
Wait until movement of the hands stop. - Press and hold button A for 3 seconds or more.
The compass hand points the 3 o'clock position.
- Press and hold button B for 3 seconds or more.
The compass hand points the direction of declination (east or west) and the 2.5 m (25 ft) hand shows the degree of declination by pointing a second tick mark.
- Press button B to choose east or west.
W E Choose this when the direction of declination is west (W). Choose this when the direction of declination is east (E). 
Each time you press the button, choice of "E" and "W" changes alternately.
- Press button A to set the degree of declination.
For example, to set "7º W", set the hands as shown on the figure below.
Indication keeps changing while you are pressing and holding the button.
- Press and hold button B for 3 seconds or more.
Declination correction completes and compass function starts.
It may take a moment to indicate the compass direction.
Wait until movement of the hands stop. - Press button A to finish the procedure.
Pressing the buttons A and B at the same time before finishing step 5 resets the values of 2 point correction and declination correction and the watch returns to compass function.
About altitude measurement/using the compass
Altitude measurement (troubleshooting)
| Symptom | Cause and remedies |
|---|---|
| Indicated altitude is different from actual one. | This watch measures atmospheric pressure with a pressure sensor and indicates altitude calculated from the measurement result.
Use the function executing altitude calibration as atmospheric pressure may vary due to season or change of weather. |
| Hands' movement are unstable during altitude measurement. | Turbulence or a little change of pressure may affect the altitude indication as the pressure sensor of the watch measures subtle change of atmospheric pressure. |
| Altitude indication varies even after executing altitude calibration. | Altitude measurement result may vary after surrounding atmospheric pressure drastically changes.
It is recommended that executing altitude calibration when altitude indication largely departs from expected one. |
|
The 1000 m (10000 ft) hand stops pointing the arrow.
|
The measurable altitude range of this watch is -300 m (-1000 ft) - +10000 m (32000 ft).
Check your surrounding environment and execute altitude calibration. |
|
Two hands stop pointing the mark after starting measurement.
|
Some serious problem occurs on measurement functions.
Consult a Citizen service center. |
Altitude measurement (FAQ)
| Question | Answer |
|---|---|
| Can I use the function for sky diving or paragliding? | You cannot use it for activities with sudden change of atmospheric pressure as the watch's indication cannot follow change of altitude. |
| Can I use the function for diving? | You cannot use it for diving as the watch measures atmospheric pressure and calculates altitude and it cannot measure water pressure and calculate water depth. You can wear the watch in water as far as its water resistance allows. |
| Can I use the function in an airplane? | The function cannot work properly in an airplane as air pressure is kept constant there. |
Using the compass (troubleshooting)
| Symptom | Cause and remedies |
|---|---|
| North on the watch's indication is different from that on a map. | A compass based on geomagnetism measurement points to the magnetic north, not the north on a map (true north). The indication can be calibrated to point to the true north by executing declination correction. |
| The compass hand takes biased movement. | Use the compass keeping the watch level. Check whether items emitting electromagnetic waves near around. The watch may be magnetized. Execute 2 point correction. |
| Cannot perform 2 point correction | Proper measurement and correction may become difficult in places where geomagnetism is interfered such as in a house or where strong magnetism is generated. Check your surrounding environment and execute 2 point calibration. |
|
The compass hand stops pointing the mark.
|
Abnormal magnetism is detected by the sensor. Check your surrounding environment and execute measurement again. Consult a Citizen service center if the symptom is not improved. |
|
Two hands stop pointing the mark after starting measurement.
|
Some serious problem occurs on measurement functions. Consult a Citizen service center. |
