Casio 3040 How a Radio-controlledWatch Works, Reception Ranges, What is a radio-controlledwatch, Calibration Signal, Location, Receiving the Calibration Signal

Operation Guide 3040

How a Radio-controlled Watch Works

Reception Ranges

The table below shows the time calibration signal that the watch receives when a particular city code is selected as your Home City.

•For information about selecting a Home City, see “To configure Home City settings”. See the “City Code List” for more information.

What is a radio-controlled watch?

Your radio-controlled watch is designed to receive a time calibration signal that contains standard time data and adjust its current time setting accordingly.

Calibration Signal

• The Japanese calibration signal (Call Sign: JJY) is maintained by

the National Institute of Information and Communications

Technology (NICT). It is transmitted 24 hours a day from the Mt.

Otakadoya transmitter (40 kHz) located in Tamura-gun,

Home City (Supports signal reception)	Receivable Transmitter

TYO, SEL, TPE, BJS, HKG	Japanese (JJY) time calibration signal

HNL, ANC, YVR, LAX, YEA, DEN, MEX, YWG, CHI, MIA, YTO,	United States (WWVB) time calibration signal
NYC, YHZ, YYT	United States (WWVB) time calibration signal

Transmitter

Long-wave time calibration signal

Fukushima Prefecture, and from the Mt. Hagane transmitter (60

kHz) located on the border between Saga Prefecture and

Fukuoka Prefecture.

• The U.S. calibration signal (Call Sign: WWVB) is transmitted by

the National Institute of Standards and Technology (NIST) from

Fort Collins, Colorado.

• The U.K. calibration signal (Call Sign: MSF) is transmitted by the

National Physical Laboratory (NPL) from Rugby, Warwickshire.

• The German calibration signal (Call Sign: DCF77) is transmitted

LIS, LON, MAD, PAR, ROM, BER, STO, ATH, MOW

English (MSF) and German (DCF77) time calibration signal

•The BJS (Beijing), HKG (Hong Kong), HNL (Honolulu), ANC (Anchorage), and MOW (Moscow) city codes also support time calibration signal reception. Reception from the applicable locations is possible under favorable conditions.

Transmitter Location	England (MSF), Germany (DCF77)
	1000km

Cesium
atomic clock	Watch

After the watch receives the time calibration signal, it performs internal calculations to determine the current time. Because of this, there may be an error of up to one second in the displayed time.

by Physikalisch - Technische Bundesanstalt (PTB) from

Mainflingen.

The time data of the Japanese calibration signal (Call Sign: JJY) is maintained by the Japan Standard Time Group of the National Institute of Information and Communications Technology (NICT). Note that transmission of the standard wave may be interrupted occasionally due to maintenance, lightning, etc. For more information, visit the website of the Japan Standard Time Group of the National Institute of Information and Communications Technology (NICT) at the following URL.

http://jjy.nict.go.jp

•Note that the above URL is subject to change.

		United States (WWVB)	1500km
		United States (WWVB)
500km		Mt. Otakadoya
500km	500km	(40kHz)
Mt. Hagane		Rugby
(60kHz)		1000km
		1000km
	1000km	500km
	1000km
	Japan (JJY)	3000km
	Japan (JJY)	Fort Collins	Mainflingen
		Fort Collins	Mainflingen

•Certain conditions can make reception impossible even when the watch is within one of the reception ranges shown above. Signals become weaker outside of the smaller circles indicated by dashed lines, so the reception environment has a greater effect on signal reception.

The following can also affect signal reception: geographic contours, structures, weather, climate, time of day (afternoon, evening), noise.

Location

Reception is difficult and may even be impossible in the locations described below. Avoid such locations when performing signal reception.

•You should think of your watch operating like a radio or TV when it is receiving the calibration signal.

Receiving the Calibration Signal

There are two methods you can use in order to receive the time calibration signal.

•Auto Receive, six times a day: Midnight, 1:00, 2:00, 3:00, 4:00, and 5:00 a.m.

•Manual receive (You initiate reception using a button operation.)

•Any time a signal receive operation is successful, no more auto receive operations are performed that day.

•The watch is set up for auto receive at the factory, so all you need to do is to place it in a location that allows good reception each night. Note however that auto receive is turned off for the following city codes: BJS, HKG, HNL, ANC, and MOW.

For information about turning auto receive on and off, see “To turn auto receive on and off”.

•Auto receive will be performed whenever the Timekeeping Mode (see “Modes and Indicators”) Home Time reaches one of the times shown above.

•The auto receive start time differs according to the current home city and summer time setting.

Among or near buildings

Next to a household appliance or office equipment (TV, speaker, fax, computer, cell phone, etc.)

Near high-voltage lines	Inside a vehicle
	(automobile, train, plane, etc.)

In a location where there is	Near mountains
radio interference (construction
site, airport, etc.)

Home City				Auto Receive Start Times
		1	2	3	4	5	6

TYO, SEL, TPE, BJS,	Standard Time	00:00 a.m.	01:00 a.m.	02:00 a.m.	03:00 a.m.	04:00 a.m.	05:00 a.m.
HKG

HNL, ANC, YVR, LAX, YEA,	Standard Time	00:00 a.m.		02:00 a.m.	03:00 a.m.	04:00 a.m.	05:00 a.m.
DEN, MEX, YWG, CHI, MIA,			01:00 a.m.
	Summer Time
YTO, NYC, YHZ, YYT
	Standard Time	01:00 a.m.	02:00 a.m.	03:00 a.m.	04:00 a.m.	05:00 a.m.	00:00 the following
							morning
LIS, LON
	Summer Time	02:00 a.m.	03:00 a.m.	04:00 a.m.	05:00 a.m.	00:00 the following	01:00 the following

						morning	morning

	Standard Time	02:00 a.m.	03:00 a.m.	04:00 a.m.	05:00 a.m.	00:00 the following	01:00 the following
MAD, PAR, ROM, BER,						morning	morning
STO	Summer Time	03:00 a.m.	04:00 a.m.	05:00 a.m.	00:00 the following	01:00 the following	02:00 the following
					morning	morning	morning

	Standard Time	03:00 a.m.	04:00 a.m.	05:00 a.m.	00:00 the following	01:00 the following	02:00 the following

If you are experiencing problems with reception, move away from the types of locations described above to a location with better reception, and try again.

ATH					morning	morning	morning
	Summer Time	04:00 a.m.	05:00 a.m.	00:00 the following	01:00 the following	02:00 the following	03:00 the following
				morning	morning	morning	morning

	Standard Time	04:00 a.m.	05:00 a.m.	00:00 the following	01:00 the following	02:00 the following	03:00 the following
				morning	morning	morning	morning
MOW
	Summer Time	05:00 a.m.	00:00 the following	01:00 the following	02:00 the following	03:00 the following	04:00 a.m.

			morning	morning	morning	morning