Using The Tachymeter (When Provided); All-Reset - Citizen E21 Instruction Manual

13. Using the Tachymeter (When Provided)

The tachymeter feature is used to measure traveling speed such as that of an automobile.
In the case of this watch, the average speed can be approximately determined for a certain
distance by measuring how many seconds it takes to travel 1 kilometer (measuring range:
maximum 60 seconds). To determine average speed, start the chronograph simultaneous
to the start of measurement. Stop the chronograph when the vehicle has traveled 1 kilometer.
An approximation of the average speed over that distance can be determined by the position
of the chronograph second hand at that time.
Chronograph second hand
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60
Tachymeter
Example:
If it takes 45 seconds to travel 1
kilometer, then the average
speed over that distance is 80
kilometers/hour.

14. All-Reset

• This watch may not keep time properly as a result of being subjected to the effects of
static electricity, magnetism, strong impact and so forth. When this happens, perform the
All-Reset procedure.
• Before performing the All-Reset procedure, make sure to charge the watch until the charge
level indicator hand is pointing at least to Level 2 and that the chronograph is in the reset
state.
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