A question about Wave Ceptor frequency reception

[Matty]

Will all Wave Ceptors pick up all the different signals (Rugby, Fort Collins, Malflingen etc)? Or are some versions of a watch tuned to a certain frequency for good?

[K@cho]

I have a GW-930D (MT-G) it can only receive the signal from Germany, a friend of mine has th GW-930DE (MT-G) it looks the same as the 930D only this one receives signals from Germany and England.
So i think there are same looking G's but were they get the timesignal from depends on the module number, the G of my friend has not the same module number as mine.

Grtz, K@cho.

[tribe125]

The majority of waveceptors do not receive all the signals. Europe and the UK are the regions that generally lose out. Some recent models do receive all the signals, and are generally known as '5 band' models (eg GW-9000). If you want to be sure, find the module number for a particular model, and then download the manual from Casio's website.

[Matty]

Well according to Wikipedia, WWVB (Fort Collins, USA) JJY (Japan) and the the National Physical Laboratory in Rugby all transmit at 60 kHz. So, it might still be possible to receive the signal if your watch is out of region. My watch is a USA region and is tuned to WWVB. Still, it's too bad Casio region-locks the watches. Be nice to know I could have accurate time anywhere.

[Marco1971]

Hi, everyone...
Only multi band wave ceptors are able to receive multi format and multi frequency long wave signals from Rugby/Anthorn (60KHz), Mainflingen (77.5KHz), Fort Collins (60KHz) and two stations from Japan (40 and 60 KHertz).
Values for carrier can be the same in Hertz but each station uses a different scheme to encode time informations.
There are many other long wave stations for time dissemination but only most common are received by radio controlled watch (wrist and non).
This is a list...

BPM, Lintong, China
Frequencies: 2500, 5000, 10000, 15000 kHz
Carrier accuracy: .f / f < 10-11 Call sign: BPM Location: Pucheng County, 70 km NE Lintong, China. Approx. 35° 00' n, 109° 30' e Operating hours: 0730-1100 on 2500 kHz, 0100-0900 on 15000 kHz,
continuous on 5000 and 10000 kHz Power: Unknown Modulation: AM; tones and voice. UTC time signals are broadcast 20 ms in advance of UTC. Identification signal: Call sign in morse and voice announcement in Chinese in minute 29 and 59 Programme: Repeats every 30 minutes, see Table 3 Time code: None, but NTSC has announced in 2003 that "BPM will disseminate the standard
time code after a technical reconstruction"
Further information: National Time Service Center (NTSC) http://kyc.ntsc.ac.cn/, http://www.time.ac.cn/
00m - 10m UTC second pulses, 10 ms duration; UTC minute pulses, 300 ms duration
10m - 15m No modulation; carrier only
15m - 25m UTC second pulses, 10 ms duration; UTC minute pulses, 300 ms duration
25m - 29m UT1 second pulses, 100 ms duration; UT1 minute pulses, 300 ms duration
29m00s - 29m40s Call sign BPM in morse
29m40s - 30m00s Station identification in Chinese (female voice)
30m - 40m UTC second pulses 10 ms duration, UTC minute pulses 300 ms duration
40m - 45m No modulation; carrier only
45m - 55m UTC second pulses, 10 ms duration; UTC minute pulses, 300 ms duration
55m - 59m UT1 second pulses, 100 ms duration; UT1 minute pulses, 300 ms duration
59m00s - 59m40s Call sign BPM in morse
59m40s - 60m00s Station identification in Chinese (female voice)

Table 3. BPM hourly transmission schedule

BSF, Chung-Li, Taiwan
Frequencies: 5000, 15000 kHz
Carrier accuracy: .f / f < 2 x 10-11
Call sign: BSF
Location: Chung-Li, 24° 57’ n, 121° 09’ e
Operating hours: Continuous except from xx35 - xx40 each hour
Power: Unknown
Modulation: AM; 1000 Hz tones and voice DUT1 code is transmitted by emphasized (lengthened) pulses. When the emphasis is on seconds 1 through 8, DUT1 is positive; and when DUT1 is negative, seconds 9 through 16 are used (DUT1 is the difference between the astronomical time scale UT1 and the atomic time scale UTC, in 0.1 s steps. Range is ±0.8 s).
Identification signal: Call sign in morse and announcement in minute 09, 19, 29, 49, 59 (not in 39) Programme: See Table 4 Time code: None
Further information: National Standard Time Service. Chungghwa Telecom Co. Ltd. http://www.stdtime.gov.tw
00m - 05m Second pulses of 5 ms duration, minute pulses of 300 ms duration. 1000 Hz tone is tranmitted continuously except for a period of from 40 ms before to 40 ms after each pulse
05m - 09m As 00m - 05m but without 1000 Hz tone transmissions
09m Call sign and time in morse and announcement in Chinese
10m - 15m As 00m - 05m
15m - 19m As 00m - 05m but without 1000 Hz tone transmissions
19m Call sign and time in morse and announcement in Chinese
20m - 25m As 00m - 05m
25m - 29m As 00m - 05m but without 1000 Hz tone transmissions
29m Call sign and time in morse and announcement in Chinese
30m - 35m As 00m - 05m
35m - 40m Silence
40m - 45m As 00m - 05m
45m - 49m As 00m - 05m but without 1000 Hz tone transmissions
49m Call sign and time in morse and announcement in Chinese
50m - 55m As 00m - 05m
55m - 59m As 00m - 05m but without 1000 Hz tone transmissions
59m Call sign and time in morse and announcement in Chinese

Table 4. Schedule

CHU, Ottawa, Canada
Frequencies: 3330, 7335, 14670 kHz
Carrier accuracy: .f / f < 5 x 10-12
Call sign: CHU
Location: Ottawa, 45° 18' n, 75° 45' w
Operating hours: Continuous
Power: 3 kW on 3330 and 14670 kHz, 10 kW on 7335 kHz
Modulation: AM (USB only), tones and voice
The first minute of each hour commences with a 1 s pulse of 1000 Hz tone, followed by 9 s of silence, and then the normal pattern of 0.3 s pulses of 1000 Hz at one-second intervals. The normal pattern for each of the next 59 minutes starts with a 0.5 s 1000 Hz pulse.
DUT1 code is transmitted in seconds 1 through 16 (DUT1 is the difference between the astronomical time scale UT1 and the atomic time scale UTC, rounded to 0.1 s. The range of DUT1 is -0.8 s to +0.8 s). The DUT1 code consists of emphasized (split) seconds markers, so that a double tone is heard. When the emphasis is on seconds 1 through 8, DUT1 is positive; and when DUT1 is negative, seconds 9 through 16 are used.
The pulse in second 29 is omitted. Following the normal pulse at 30 seconds, for a 9 s period, 1000 Hz pulses of 0.01 s occur, each followed by the CHU time code (see below). The pulses between 40 and 50 seconds are of normal length.
Identification signal: Alternating French/English station identification in the last 10 seconds of each minute, followed by UTC time announcement, valid for the following minute. During the announcement period, the 1000 Hz seconds pulses are shortened to “ticks”.
Time code: A time code is sent in seconds 31 through 39. The data is in the form of an FSK data stream, with 2225 Hz mark and 2025 Hz space. Each packet consists of ten bytes. There are two formats, format B for second 31 and format A for seconds 32 through 39. See Tables 5 and 6 for details.
Further information: INMS Time Services. http://inms-ienm.nrc-cnrc.gc.ca/
0 - 10 ms Ticking noise (10 cycles of 1000 Hz)
10 - 123.33 ms 2225 Hz mark tone
123.33 - 500 ms Ten bytes of data at 300 bits per second. Each byte is encoded as one start bit, eight data bits and two stop bits
500 - 510 ms 2225 Hz mark tone for 10 ms
510 ms - 1000 ms Silence until the end of the second

Table 5. Structure of seconds 31 through 39
Byte Data Meaning of data
1 D36 D3D2D1 is the day of the year. 6 is a constant.
2 D1D2
3 H1H2 H2H1 = UTC hour
4 M1M2 M2M1 = UTC minute
5 S1S2 S2S1 = UTC second
6 Byte 1…5 repeated Redundancy bytes
7
8
9
10

Table 6a. Format A, transmitted in seconds 32 through 39. Each nibble is a BCD digit. Note that the nibbles are transmitted in swapped order.
Byte Data Meaning of data
1 ZX Z is the absolute value of DUT1 in tenths of a second. X is encoded as follows: Bit 0 (rightmost; transmitted first): Sign of DUT1 (0 = +). Bit 1: Leap second warning. One second will be added. Bit 2: Leap second warning. One second will be subtracted. Bit 3: Even parity bit for this nibble.
2 Y3Y4 Y4Y3Y2Y1 = year
3 Y1Y2
4 T1T2 T2T1 = Difference between TAI and UTC in seconds. The International Atomic Time TAI does not use leap seconds. Some other technical time scales are based on TAI, to avoid leap seconds. TAI can be calculated from UTC by: TAI = UTC + TT.
5 A1A2 A2A1 is the code number for the daylight saving time pattern in effect at this time across all time zones of Canada. The current serial number is 01, effective since 1988.
6 Byte 1…5 inverted (1’s complement) Redundancy bytes
7
8
9
10

Table 6b. Format B, transmitted in second 31. Each nibble, except X, is a BCD digit. Note that the nibbles are transmitted in swapped order.

DCF77, Mainflingen, Germany
Frequency: 77.5 kHz
Carrier accuracy: .f / f < 1 x 10-12 (1 d average), < 2 x 10-13 (100 d average)
Call sign: DCF77
Location: Mainflingen, near Frankfurt, Germany, 50° 01’ n, 09° 00’ e
Operating hours: Continuous
Power: 50 kW. Estimated radiated power 30 kW
Antenna Top-loaded vertical, 150 m high. The backup antenna is 200 m high.
Modulation: Amplitude keying. The amplitude is reduced to 25% for 100 ms or 200 ms, starting
with the full second, except for second 59 ( 60 in case of a positive leap second). A
carrier reduction of 200 ms corresponds to a logical 1.
Pseudorandom phase shift keying (PRPSK), see Figure 1. At the receiver side the
second markers can be determined by a cross correlation technique, which is
much more accurate than measuring the arrival time of the amplitude-keyed time
signals. This modulation causes the “noisy” sound of the DCF77 signal.

Identification signal: The callsign is transmitted twice in Morse code in minutes 19, 39 and 59, seconds 20 to 32, in AM; the amplitude is switched between 85% and 100% with a 250 Hz rectangular waveform. This signal will probably be omitted in the future.
Time code: See Table 7 on page 11
Further information: Physikalisch-Technische Bundesanstalt. http://www.ptb.de

Figure 1a. A pseudo random sequence of 512 steps is generated by means of a feedback shift register. Not shown is a mechanism to force the shift register out of the “all zero state” at the beginning of the sequence. Sequence inversion keying is used: The phase shift is inverted if a logical “1” is transmitted.

Figure 1b. The 512 step pseudorandom sequence starts 200 ms after the full second, defined by the falling edge of the amplitude, and ends about 7 ms before the next second. This ensures that the falling edge is not disturbed. The transmitter phase is shifted by ±10 degrees. Note: Timing in this sketch is not to scale.

France Inter, Allouis, France
Frequency: 162.0 kHz
Carrier accuracy: .f / f < 1 x 10-12 (1 d average)
Call sign: None. Broadcast station with "inaudible" time subcode
Location: Allouis, NW Bourges, 47° 10' n, 02° 12' e
Operating hours: Continuous
Power: 2000 kW (1000 kW at night 00 - 06h)
Modulation: AM broadcast with additional phase-shift keying of ±1 Rad (57 degrees) for time
code, see figure 2
Identification signal: None
Time code: Similar to DCF77. See Table 7 on page 11
Further information: http://www.emetteurs.fr.fm (private site)

+1
+1
0
0
Time
-1
-1


Figure 2. Phase shift keying of France Inter on 162 kHz. The rise and fall time of 1 Rad / 25 ms corresponds to a frequency shift of ± 6 Hz, which is inaudible in the audio broadcast signal. There are either one or two cycles of 100 ms at the begin of each second (except second 59), depending on whether a logical "0" or a "1" is transmitted.

HBG, Prangins, Switzerland
Frequency: 75.0 kHz
Carrier accuracy: .f / f < 2 x 10-12
Call sign: HBG
Location: Prangins, 46° 24' n, 06° 15' e
Operating hours: Continuous
Power: 20 kW
Modulation: Amplitude keying: Amplitude reduced for 100 ms or 200 ms, starting with the full second, except in second 59. A carrier reduction of 200 ms corresponds to a logical 1. Second 00 is marked by a double pulse, i.e. two 100 ms carrier reductions, spaced by a 100 ms full carrier interval. There are three pulses at the full hour and four pulses every 12 hours.
Identification signal: None
Time code: Similar to DCF77. See Table 7
Further information: Bundesamt fόr Metrologie und Akkreditierung Schweiz (METAS) http://www.official-time.ch, http://www.metas.ch
Second Value Meaning
0 M Minute marker; M = 0, double pulse for HBG
1 Reserved Note: The DCF77 pseudo random PSK is inverted (= data set to logical “1”) in seconds 0 to 9. This serves as the minute identifier in the PRPSK signal.
2
3
4
5
6
7
8
9
10
11
12
13
14
15 R R = 1 if backup antenna is used (DCF77 only)
16 A1 A1 = 1 during the hour preceding Z1/Z2 change (HBG: 12 hours)
17 Z1 Z1/Z2 = 01 during MEZ (Winter); Z1/Z2 = 10 during MESZ (Summer)
18 Z2
19 A2 A2 = 1 during hour preceding leap second (HBG: 12 hours)
20 S Start of time code; always 1
21 1 BCD Minute
22 2
23 4
24 8
25 10
26 20
27 40
28 P1 Parity: Sum of bit 21…27
29 1 BCD Hour
30 2
31 4
32 8
33 10
34 20
35 P2 Parity: Sum of bit 29…34
36 1 BCD Day-of-Month
37 2
38 4
39 8
40 10
41 20
42 1 BCD Day-of-Week
43 2
44 4
45 1 BCD Month
46 2
47 4
48 8
49 10
50 1 BCD Year (00…99)
51 2
52 4
53 8
54 10
55 20
56 40
57 80
58 P3 Parity: Sum of bit 36…57
59 – No modulation

Table 7. DCF77, France Inter and HBG time code

HD2IOA, Guayaquil, Ecuador
Frequencies: 1510, 3810, 5000, 7600 kHz Note: No observations on other frequencies than 3810 kHz reported recently
Call sign: HD 2 IOA
Location: Guayaquil, 02°16’ s, 79° 54’ w
Operating hours: 1510 kHz: Continuous 3810 kHz: 0000 - 1200 5000 kHz: 1200 - 1300 7600 kHz: 1300 - 2400
Power: 1 kW on 3810, 5000 and 7600 kHz
Modulation: AM, LSB only on 3810, 5000 and 7600 kHz. 1000 Hz tone pulses and voice. See Table 8
Identification signal: On 3810 and 7600 kHz, the call sign is transmitted in 59m15s through 59m50s of every hour
Further information: Instituto Oceanogrαfico de la Armada del Ecuador. http://www.inocar.mil.ec/instit/d_ayuda/elect.php
00s Minute pulse, 300 ms duration
01s - 28s Second pulses, 100 ms duration
29s Silence
30s - 50s Second pulses, 100 ms duration
51s Silence
52s - 58s Voice announcement of time
59s Silence

Table 8. Minute schedule

JJY, Japan
Frequencies: 40.0 kHz and 60.0 kHz
Carrier accuracy: .f / f < 10-12
Call sign: JJY
Location 40 kHz: Ohtakadoyayama, Fukushima prefecture, 37° 22’ n, 140° 51’ e
Location 60 kHz: Haganeyama, Saga prefecture, Kyushu Isl., 33° 28’ n, 130° 11’ e
Operating hours: Continuous
Power: 50 kW (radiated power > 10 kW)
Antenna: Top-loaded umbrella type antenna. 40 kHz: 250 m high, 60 kHz: 200 m high
Modulation: Amplitude keying: Positive pulses of 0.8 s duration (time code binary zero), 0.5 s
(binary one) and 0.2 s (various markers). Amplitude in-between pulses is 10% of pulse level.
Identification signal: Call sign in morse in minute 15 and 45 in second 40 through 48
Time code: Japan Standard Time in binary coded decimal (BCD), see Table 9
Further information: National Institute of Information and Communications Technology NICT, Japan Standard Time Group. http://jjy.nict.go.jp/
Second Value Meaning Second Value Meaning
0 M Minute marker (0.2 s) 30 8 BCD Day; 1 = January 1
1 40 31 4
2 20 32 2
3 10 33 1
4 “0” BCD Minute 34 “0” (always 0.8 s)
5 8 35 “0”
6 4 36 PA1 Parity bits. PA1= (20h + 10h + 8h + 4h + 1h) mod 2, PA2 = (40m + 20m + 10m + 8m + 4m + 2m + 1m) mod 2
7 2 37 PA2
8 1 38 SU1 Spare bit or summer time information, see Table 9c
9 P1 Position marker (0.2 s) 39 P4 Position marker (0.2 s)
10 “0” 40 SU2 Spare bit or summer time information, see Table 9c
11 “0” (always 0.8 s) 41 80 BCD Year
12 20 42 40
13 10 43 20
14 “0” 44 10
15 8 BCD Hour 45 8
16 4 46 4
17 2 47 2
18 1 48 1
19 P2 Position marker (0.2 s) 49 P5 Position marker (0.2 s)
20 "0" 50 4 Day of week; 0 = Sunday
21 “0” (always 0.8 s) 51 2
22 200 52 1
23 100 53 LS1 LS1, LS2 = 00 = no leap second within one month, 11 = positive, 10 = negative leap second within one month
24 “0” 54 LS2
25 80 BCD Day; 1 = January 1 55 "0" (always 0.8 s)
26 40 56 “0”
27 20 57 “0”
28 10 58 “0”
29 P3 Position marker (0.2 s) 59 P0 Position marker (0.2 s)

Table 9a. JJY time code (except in minute 15 and 45, see Table 9b) Table 9b. JJY time code in minute 15 and 45. Shaded areas: Differences to Table 9a
Second Value Meaning Second Value Meaning
0 M Minute marker (0.2 s) 30 8 BCD Day; 1 = January 1
1 40 31 4
2 20 32 2
3 10 33 1
4 “0” BCD Minute 34 “0” (always 0.8 s)
5 8 35 “0”
6 4 36 PA1 Parity bits. PA1= (20h + 10h + 8h + 4h + 1h) mod 2, PA2 = (40m + 20m + 10m + 8m + 4m + 2m + 1m) mod 2
7 2 37 PA2
8 1 38 "0"
9 P1 Position marker (0.2 s) 39 P4 Position marker (0.2 s)
10 “0” (always 0.8 s) 40 Call sign
11 “0” 41
12 20 42
13 10 43
14 “0” 44
15 8 BCD Hour 45
16 4 46
17 2 47
18 1 48
19 P2 Position marker (0.2 s) 49 P5 Position marker (0.2 s)
20 "0" 50 ST1 Station maintenance information, see Table 9d
21 “0” (always 0.8 s) 51 ST2
22 200 52 ST3
23 100 53 ST4
24 “0” 54 ST5
25 80 BCD Day; 1 = January 1 55 ST6
26 40 56 “0” (always 0.8 s)
27 20 57 “0”
28 10 58 “0”
29 P3 Position marker (0.2 s) 59 P0 Position marker (0.2 s)

SU1 SU2 Meaning
0 0 No change to summer time within 6 days
1 0 Change to summer time within the next 6 days
0 1 During summer time: No change to regular time within 6 days
1 1 During summer time: Summer time will end within 6 days

Table 9c. Summertime information bits SU1 and SU2
Starting ST1 ST2 ST3 Meaning
0 0 0 No information available
0 0 1 Transmission break within 7 days
0 1 0 Transmission break within 3 to 6 days
notice 0 1 1 Transmission break within 2 days
1 0 0 Transmission break within 24 hours
1 0 1 Transmission break within 12 hours
1 1 0 Transmission break within 2 hours

Status information ST4 Meaning
1 Daytime only
0 All day, or no information available

Period information ST5 ST6 Meaning
0 0 No information available
0 1 More than 7 days or unknown period
1 0 2 to 6 days
0 1 Less than 2 days

Table 9d. Station maintenance information bits ST1…ST6

LOL, Buenos Aires, Argentina
Frequencies: 5000, 10000, 15000 kHz (5000 and 10000 announced temporary inactive in 2002 and 2003)
Carrier accuracy: .f / f < 2 x 10-10
Call sign: LOL
Location: Buenos Aires, 34°37’s, 58° 21’w
Operating hours: 1100-1200, 1400-1500, 1700-1800, 2000-2100, 2300-2400
Power: 2 kW
Modulation: AM; 440 Hz and 1000 Hz tones and voice The begin of each second is marked with a 5 ms long tick (5 periods of 1000 Hz), except second 59.
Identification signal: Call sign in morse and announcement, see Table 10
Programme: See Table 9
Time code: None
Further information: Observatorio Naval Buenos Aires. http://www.hidro.gov.ar
Minutes after the full hour Transmission content
00 - 03 10 - 13 20 - 23 30 - 33 40 - 43 50 - 53 1000 Hz tone
03 - 05 13 - 15 23 - 25 33 - 35 43 - 45 53 - 55 Call sign “LOL” in Morse, announcement “Observatoria Naval – Argentina” and time announcement
05 - 08 15 - 18 25 - 28 35 - 38 45 - 48 440 Hz tone. From 55m to 58m silence except second tics
08 - 10 18 - 20 28 - 30 38 - 40 48 - 50 58 - 60 Call sign “LOL” in Morse, announcement “Observatoria Naval – Argentina” and time announcement
Table 10. LOL hourly transmission scheme



MSF, Rugby/Anthorn, United Kingdom
Frequency: 60.0 kHz
Carrier accuracy: .f / f < 2 x 10-12
Call sign: MSF
Location: Rugby, England, 52° 22’ n, 01° 11’ w (until 31 March 2007) Anthorn, England, 54° 55' n, 03° 15' w (from 01 April 2007)
Operating hours: Continuous
Power: 15 kW estimated "equivalent monopole radiated power" (ERMP)
Modulation: On-off keying (A1B), see Figure 3
Time code: See Table 11. In minutes lengthened or shortened by a positive or negative leap second, the second numbers 17 through 59 are correspondingly increased or decreased by one (i.e. during these 61- or 59-second minutes, the position of the time and date code is shifted by one second relative to the start of the minute).
Further information: National Physics Laboratory Time & Frequency Service. http://www.npl.co.uk/time/
carrier envelope second marker


Bit A
Bit B
100 ms
100 ms
marker preceded by
carrier off = logical 1
at least 500 ms carrier

Fig 3. MSF amplitude keying
Data Bit A (100 - 200 ms after full second) Data Bit B (200 - 300 ms after full second)
Second Value Meaning Second Value Meaning
0 “1” Minute marker 0 “1” Minute marker
1 1 +100 ms DUT1 Difference between astronomical time UT1 and atomic time UTC, rounded to the nearest 100 ms in the range ±800 ms. Example: If DUT1 = +0.3, data bit B of seconds 1…3 are set to 1
2 2 +100 ms
3 3 +100 ms
4 4 +100 ms
5 5 +100 ms
6 6 +100 ms
7 7 +100 ms
8 Reserved. Currently set to “0” 8 +100 ms
9 9 -100 ms
10 10 -100 ms
11 11 -100 ms
12 12 -100 ms
13 12 -100 ms
14 14 -100 ms
15 15 -100 ms
16 16 -100 ms
17 80 17 Reserved. Currently set to “0”
18 40 18
19 20 19
20 10 Binary-Coded-Decimal (BCD) 20
21 8 Year (00…99) 21
22 4 22
23 2 23
24 1 24
25 10 25
26 8 26
27 4 BCD Month (01…12) 27
28 2 28
29 1 29
30 20 30
31 10 31
32 8 32
33 4 BCD Day-of-Month (01…31) 33
34 2 34
35 1 35
36 4 36
37 2 BCD Day-of-Week (0…6; 0 = Sunday) 37
38 1 38
39 20 39
40 10 40
41 8 41
42 4 BCD Hour (00…23) 42
43 2 43
44 1 44
45 40 45
46 20 46
47 10 47
48 8 BCD Minute (00…59) 48
49 4 49
50 2 50
51 1 51
52 “0” 52
53 “1” 53 “1” during 61 minutes before Bit 58B changes
54 “1” This sequence 01111110 never 54 Parity: Sum of bit 17A…24A + 1
55 “1” appears elsewhere in bit A, so it 55 Parity: Sum of bit 25A…35A + 1
56 “1” uniquely identifies the following minute 56 Parity: Sum of bit 36A…38A + 1
57 “1” marker. 57 Parity: Sum of bit 39A…51A + 1
58 “1” 58 “1” during Summer time (UK civil time = UTC + 1)
59 “0” 59 “0”
Table 11. MSF time code



RBU, Moscow, Russia
Frequency: 66.67 kHz (= 200 kHz divided by 3)
Carrier accuracy: .f / f < 2 x 10-12
Call sign: RBU
Location: Moscow, 55° 48’ n, 38° 18’ e
Operating hours: Continuous
Power: 10 kW
Modulation: Carrier keyed off for 5 ms at 100 ms intervals. AM subcarrier 100 Hz and 312.5 Hz
(modulation index m = 0.7) for second and minute identification and time code, see Figure 4.
Time code: See Table 12
second carrier envelope10 ms

312.5 Hz 312.5 Hz or 100 Hz





5 ms 5 ms


Figure 4a. Signal detail
Figure 4b. Relationship between subcarrier frequencies and data

Data Bit 1 Data Bit 2
Second Value Meaning Second Value Meaning
0 “1” 0 “1”
1 “0” 1 +100 ms DUT1 Difference between astronomical time UT1 and atomic time UTC, rounded to the nearest 100 ms in the range ±800 ms. Example: If DUT1 = +0.3, data bit 2 of seconds 1…3 are set to 1
2 “0” 2 +100 ms
3 * 3 +100 ms
4 * 4 +100 ms
5 * 5 +100 ms
6 * 6 +100 ms
7 ± (1 = negative) 7 +100 ms
8 “0” dUT1 8 +100 ms
9 “0” 9 -100 ms
10 “0” additional 20 ms steps for increased accuracy of DUT1 10 -100 ms
11 * 11 -100 ms
12 * 12 -100 ms
13 * 12 -100 ms
14 * 14 -100 ms
15 ± (1 = negative) 15 -100 ms
16 “0” 16 -100 ms
17 “0” 17 “0”
18 ± (1 = negative) 18 8 000 TJD The 4 least significant digits of the Julian day number. Example: For 3 December 2000 at 0 UTC, JD is 2451881.5, TJD is 1881. Note: TJD does not change at 12 UTC, although the Julian day begins at noon.
19 10 .UT 19 4 000
20 8 20 2 000
21 4 Difference between transmitted 21 1 000
22 2 time and UTC, in hours (+3 in winter, +4 in summer) 22 800
23 1 23 400
24 0 24 200
25 80 25 100
26 40 26 80
27 20 27 40
28 10 Y 28 20
29 8 29 10
30 4 year 30 8
31 2 31 4
32 1 32 2
33 10 33 1
34 8 M 34 reserved
35 4 35
36 2 month 36
37 1 37
38 4 38
39 2 dw 39
40 1 day of week (1 = monday) 40
41 20 41
42 10 42
43 8 dM 43
44 4 44
45 2 day of month 45
46 1 46
47 20 47
48 10 48
49 8 h 49 TJD sec. 18-25 parity bits (even parity)
50 4 hour 50 TJD sec. 26-33
51 2 51 reserved
52 1 52
53 40 53 .UT
54 20 54 Y
55 10 m 55 M + dW
56 8 56 dM
57 4 minute 57 h
58 2 58 m
59 1 59 0
Table 12: RBU time code transmitted in data bits 1 and 2, valid for the following minute



RWM, Moscow, Russia
Frequencies: 4996, 9996, 14996 kHz Carrier accuracy: .f / f < 1 x 10-11 Call sign: RWM Location: Moscow, 55° 48’ n, 38° 18’ e Operating hours: Continuous Power: 5 kW on 4996 and 9996 kHz, 8 kW on 14996 kHz Modulation: On-off keying (A1B) Identification signal: Call sign in Morse in minutes 09 and 39 Programme: Schedule repeats every 30 minutes, see Table 13 Time code: None
00m00s - 07m55s 30m00s - 37m55s Unmodulated carrier
08m00s - 09m00s 38m00s - 39m00s No transmission
09m00s - 09m55s 39m00s - 40m55s "rwm rwm rwm …" in Morse code (before 2004: “vvv cq cq cq de rwm rwm rwm”)
10m00s - 19m55s 40m00s - 49m55s 1 Hz pulses with UT1-UTC code, see Figure 5. Pulse duration = 100 ms, minute pulse = 500 ms
20m00s - 29m55s 50m00s - 59m55s 10 Hz pulses. Duration = 20 ms, second pulse = 40 ms, minute pulse = 500 ms
Table 13. RWM hourly transmission schedule


pulse 1...8 doubled pulse 9...16 doubled pulse 21...24 doubled pulse 31...34 doubled ifDUT1 > 0 if DUT1< 0 if dUT1 > 0 ifdUT1 < 0

0 5 1015 202530 35
Second
Figure 5. Coding of the deviation between astronomical time UT1 and atomic time UTC. The difference in seconds is given by 0.1 x DUT1 + 0.02 x dUT1. In this example, DUT1 is +4 and dUT1 is -3, hence UT1 - UTC = +0.34 seconds.

RTZ, Irkutsk, Russia
Frequency: 50.0 kHz
Carrier accuracy: .f / f < 5 x 10-12
Call sign: RTZ
Location: Irkutsk, Russia, 52° 26’ n, 103° 41’ e
Operating hours: Winter 22 - 21, summer 21 - 20 UTC (01 - 24 Moscow time). Note: The
transmission is often resumed before the end of the scheduled one-hour break.
Power: 10 kW
Modulation: On-off keying (A1B)
Identification signal: Call sign in Morse in minute 05
Programme: Repeats every 60 minutes, see Table 14
Time code: None
00m00s - 04m55s 1 Hz pulses with UT1-UTC code similar to RWM Moscow, see Figure 5
05m00s - 06m00s Call sign RTZ in Morse code
06m00s - 58m55s Unmodulated carrier
59m00s - 59m55s 10 Hz pulses
Table 14. RTZ transmission schedule



RAB99, RJH63, RJH66, RJH69, RJH77, RJH99
Frequency: 25.0 kHz. Additional transmissions on 20.5, 23.0, 25.1 and 25.5 kHz, see Table 15
Carrier accuracy: .f / f < 5 x 10-12 Call signs: Russian Navy related call signs; See Table 14 Locations: Various Russian Navy sites; See Table 14 Operating hours: See Table 14 Power: 300 kW Modulation: On-off keying (A1B) Identification signal: Call sign in Morse in minute 06 Programme: See Table 16 Time code: None
Further information: Trond Jabobsen: The Russian VLF Time-Signal Stations “Beta”, December 2000. Available at http://www.vlf.it.
Call sign Location Operating hours winter Operating hours summer No transmission (day of month, see Note 1)
RAB99 Khabarovsk, Russia 48° 30’n, 134° 50’e 0206 - 0240 0606 - 0640 0106 - 0140 ? 0506 - 0540 ? 10., 20., 30.
RJH63 Krasnodar, Russia 44° 46’n, 39° 34’e 1106 - 1140 1006 - 1040 3., 13., 23.
RJH66 Bishkek, Kirgizia 43° 03’n, 73° 37’e 0406 - 0447 1006 - 1047 0306 - 0347 0906 - 0947 6., 16., 26.
RJH69 Molodecno, Belorussia 54° 28’n, 26° 47’e 0706 - 0747 0606 - 0647 2., 12., 22.
RJH77 Arkhangelsk, Russia 64° 22’n, 41° 35’e 0906 - 0947 0806 - 0847 4., 14., 24.
RJH99 Nizhniy Novgorod, Russia 56° 11’n, 43° 57’e 0506 - 0547 0406 - 0447 8., 18., 28.
Note 1: Definetely no transmission on these dates, but emissions are often missing at other times as well. About once per year, each station has been noted off air for a period of weeks to months.
Table 15. Call signs, locations and transmission times (UTC)


Transmitting time RJH66/69/77/99 Transmitting time RJH63, RAB99 Transmitted pattern
06m00s - 07m00s 06m00s - 07m00s Call sign in morse code
07m00s - 10m00s 07m00s - 09m00s Unmodulated carrier
10m00s - 13m00s 09m00s - 11m00s 40 Hz pulses
13m00s - 22m00s 11m00s - 20m00s 10 Hz, 1 Hz, 1/10 Hz, 1/60 Hz pulses
22m00s - 25m00s not available 40 Hz pulses
25m00s - 27m00s 20m00s - 21m00s Reserved fo tuning break
27m00s - 30m00s 21m00s - 23m00s Unmodulated carrier on 25.1 kHz
30m00s - 32m00s 23m00s - 24m00s Reserved for tuning break
32m00s - 35m00s 24m00s - 26m00s Unmodulated carrier on 25.5 kHz
35m00s - 38m00s 26m00s - 29m00s Reserved for tuning break
38m00s - 41m00s 29m00s - 31m00s Unmodulated carrier on 23.0 kHz
41m00s - 44m00s 31m00s - 34m00s Reserved for tuning break
44m00s - 47m00s 34m00s - 36m00s Unmodulated carrier on 20.5 kHz
not available 36m00s - 40m00s 50 Baud 100 Hz shift FSK on 20.5 kHz. Unknown system; word length 10 bits, block length 100 bits. Observations on RJH63 in March 2003: All blocks contained the same data; one data word was transmitted 10 times either normal or bit-inverted, according to some toggling scheme.
Table 16. Schedule


Pulse rate in Hz 40 10 1 1/10 1/60
Pulse width 12.5 ms 25 ms 100 ms 1 s 10 s

Table 17. Nominal pulse durations

WWV, Fort Collins, USA and WWVH, Kekaha, Hawaii
Frequencies: 2500, 5000, 10000, 15000, WWV also on 20000 kHz
Carrier accuracy: .f / f < 1 x 10-11
Call signs: WWV and WWVH
Location WWV: Fort Collins, Colorado, 40° 41’ n, 105° 02’ w
Location WWVH: Kekaha (Island of Kauai), 21° 59’ n, 159° 46’ w
Operating hours: Continuous
Power: Radiated power: 2.5 kW on 2.5 MHz (WWVH: 5 kW), 10 kW on 5/10/15 MHz,
2.5 kW on 20 MHZ
Modulation: AM. Various tones and voice announcements, see Table 18 and 19. Second pulses: 1000 Hz, 5 ms duration. Minute pulses: 1000 Hz, 800 ms. Hour pulses: 1500 Hz, 800 ms. Each seconds pulse is preceded by 10-ms of silence and followed by 25-ms of silence. A time code is transmitted on a 100 Hz subcarrier. Modulation level is 100% for the second, minute and hour pulses, 50% for the steady tones, 50% for the BCD time code and 75% for the voice announcements.
DUT1 code is transmitted in seconds 1 through 16 of each minute by doubling ticks. The value of DUT1 (the difference between astronomical time UT1 and UTC) is determined by the number of successive doubled ticks. If the doubled ticks are in the first 8 s, the DUT1 is positive; if they are in seconds 9-16, DUT1 is negative.
Antennas: Omnidirectional half-wave vertical antennas. WWVH uses two-element half-wave verticals for 5/10/15 MHz, radiating a cardioid pattern with the maximum gain pointed toward the west.
Identification signal: Announcement in minutes 00 and 30 (WWV), minutes 29 and 59 (WWVH)
Time code: 100 Hz subcarrier, BCD code, one bit per second. The pulses begin 30 ms after the start of a second. A 170 ms pulse represents a “0” bit, a 470 ms pulse represents a “1”. During the first second of a minute, no pulse is transmitted. A position identifier lasting 770 ms is transmitted every 10 s. See Table 20.
Further information: National Institute of Standards and Technology NIST, Time and Frequency Division. http://www.boulder.nist.gov/timefreq/
Minute Second WWV WWVH
00 s - 45 s Special announcement or 500 Hz tone 600 Hz tone
Even 45 s - 52.5 s Silent except tick UTC female voice announcement
52.5 s - 60 s UTC male voice announcement Silent except tick
00 s - 45 s 600 Hz tone Special announcement or 500 Hz tone
Odd 45 s - 52.5 s Silent except tick UTC female voice announcement
52.5 s - 60 s UTC male voice announcement Silent except tick
Table 18. WWV and WWVH minute format


Minute WWV Minute WWVH
0 Station ID 0 No audio tone
1 1 440 Hz 1-hour mark
2 440 Hz 1-hour mark 2
3 3 NIST reserved
4 NIST reserved 4
5 5
6 6
7 7
8 8 No audio tone
9 Storm information 9
10 10
11 11
12 12
13 13
14 14 No audio tone
15 GPS reports 15
16 16
17 17
18 Geo alerts 18
19 19
20 20
21 21
22 22
23 23
24 24
25 25
26 26
27 27
28 28
29 No audio tone 29 Station ID
30 Station ID 30 No audio tone
31 31
32 32
33 33
34 34
35 35
36 36
37 37
38 38
39 39
40 40
41 41
42 42
43 43 GPS reports
44 44
45 45
46 46
47 No audio tone 47
48 48 Storm information
49 49
50 50
51 51
52 52
53 53
54 54
55 55
56 56
57 57
58 58
59 No audio tone 59 Station ID
Table 19. Hourly broadcast schedules of WWV and WWVH


Second Value Meaning
0
1
2 DST indicator #2: Changes 24 hours later than bit 55
3 “1” = Leap second will be inserted at the end of the current month
4 1 Year
5 2
6 4
7 8
8
9 Position identifier P1 (770 ms duration)
10 1 Minutes
11 2
12 4
13 8
14
15 10
16 20
17 40
18
19 Position identifier P2 (770 ms duration)
20 1 Hours
21 2
22 4
23 8
24
25 10
26 20
27
28
29 Position identifier P3 (770 ms duration)
30 1 Days
31 2
32 4
33 8
34
35 10
36 20
37 40
38 80
39 Position identifier P4 (770 ms duration)
40 100 Days
41 200
42
43
44
45
46
47
48
49 Position identifier P5 (770 ms duration)
50 DUT1 sign
51 10 Year
52 20
53 40
54 80
55 DST indicator: “0” if standard itme, “1” if daylight saving time
56 0.1 s DUT1 absolute value |UT1 - UTC|
57 0.2 s
58 0.4 s
59 Position identifier P0 (770 ms duration)
Table 20. WWV and WWVH time code



WWVB, Fort Collins, Colorado, USA
Frequency: 60.0 kHz Carrier accuracy: .f / f < 1 x 10-11
Call sign: WWVB
Location: Ft. Collins, 40° 41’n, 105° 02’ w
Operating hours: Continuous
Power: 50 kW radiated power
Modulation: Amplitude shift keying. The carrier power is reduced 10 dB at the start of each second (this corresponds to an amplitude reduction by factor of about 3). If full power is restored 200 ms later, it represents a “0” bit. If full power is restored 500 ms later, it represents a “1”. Certain reference markers and position identifiers are sent by restoring full power after 800 ms.
Eventually the modulation depth will be increased from 10 dB to 20 dB. Studies indicate that the change in dropout depth may result in the equivalent of an increase in radiated power from 50 kW to as much as 80 kW. Test transmissions have been conducted May 2005.
Antenna: Two antennas, spaced 857 m apart. Each antenna is a top loaded dipole consisting of four 122-m towers arranged in a diamond shape.

Identification signal: WWVB identifies itself by advancing its carrier phase 45° at 10 minutes after the hour and returning to normal phase at 15 minutes after the hour. If the WWVB phase is plotted, this results in a phase step of approximately 2.08 ΅s.
Time code: See Table 21
Further information: National Institute of Standards and Technology NIST, Time and Frequency Division. http://www.boulder.nist.gov/timefreq/

YVTO, Caracas, Venezuela
Frequency: 5000 kHz
Carrier accuracy: .f / f < 1 x 10-10. Note: Station was observed 35 Hz high in early 2002
Call sign: YVTO
Location: Caracas, 10° 30’ n, 66° 56’ w
Operating hours: Continuous
Power: 1 kW
Modulation: AM, tones and voice
Each second starts with a 1000 Hz tone of 100 ms duration, except second 30, when the tone is omitted. A 800 Hz tone of 500 ms duration is emitted at the
beginning of a minute. Time announcement in Spanish in seconds 52 through 57.

Identification signal: Announcement in seconds 41…50: “Observatorio Naval Cagigal – Caracas – Venezuela”
Time code: None
Further information: Observatorio Naval Cagigal. http://www.dhn.mil.ve/
Second Value Meaning
0 Minute marker (800 ms)
1 40 Minutes
2 20
3 10
4
5 8
6 4
7 2
8 1
9 Position identifier P1 (800 ms)
10
11
12 20 Hours
13 10
14
15 8
16 4
17 2
18 1
19 Position identifier P2 (800 ms)
20
21
22 200 Days
23 100
24
25 80
26 40
27 20
28 10
29 Position identifier P3 (800 ms)
30 8 Days
31 4
32 2
33 1
34
35
36 + DUT1 sign. Note: Inconsistent in NIST Special Publication 432, not confirmed.
37 -
38 +
39 Position identifier P5 (800 ms)
40 0.8 s DUT1 absolute value: |UT1 - UTC|
41 0.4 s
42 0.2 s
43 0.1 s
44
45 80 Year
46 40
47 20
48 10
49 Position identifier P5 (800 ms)
50 8 Year
51 4
52 2
53 1
54
55 Leap year indicator
56 Leap second warning
57 DST flag: “1”, if daylight saving time in effect
58 As bit 57, but changes 24 hours later
59 Position identifier P0 (800 ms)
Table 21. WWVB time code



Short glossary of terms
BIPM Bureau International des Poids et Mesures. Maintains the International Atomic Time TAI. Internet address: http://www.bipm.org.
DUT1 Predicted difference between UT1 and UTC, rounded to 0.1 s. DUT1 may be regarded as a correction to be added to UTC to obtain a better approximation to UT1. The values of DUT1 are given by the IERS, from where also more precise values for UT1 - UTC can be obtained.
A number of time signal stations (still) transmit DUT1 values. Usually DUT1 is coded by emphasized (lengthened, doubled, or split) pulses in seconds 1 through 16 of each minute. The possible range is ±0.8 s. When the emphasis is on seconds 1 through 8, DUT1 is positive; and when DUT1 is negative, seconds 9 through 16 are emphasized.
Russian time signal stations transmit an additional quantity called dUT1 (with lowercase d) in order to increase the resolution of UT1 - UTC to 0.02 s.
GMT Greenwich Mean Time. Now obsolete and replaced by UTC.
IERS International Earth Rotation Service. One of the objectives of the IERS is to study and monitor earth orientation variations. IERS announces twice yearly whether there will be a leap second at the end of the following June or December. The current deviation of UT1 from UTC is also available from IERS (http://www.iers.org).
Leap second An intentional time step of one second used to adjust UTC to ensure approximate agreement with UT1. An inserted second is called a positive leap second, an omitted second is called a negative leap second. A positive leap second is presently needed about once per year; normally it is inserted at the end of June.
TAI Temps Atomique International or International Atomic Time. TAI is calculated by the BIPM from the readings of more than 200 atomic clocks located in metrology institutes around the world. It is estimated that TAI does not lose or gain with respect to an imaginary perfect clock by more than about 0.1 ΅s per year. TAI is the basis for UTC.
UT1 Mean solar time obtained from direct astronomical observation and corrected for effects of small irregularities of the Earth's rotation.
UTC Co-ordinated Universal Time. UTC corresponds in rate with TAI but differs from it by an integral number of seconds. The UTC scale is adjusted by insertion or deletion of seconds (positive or negative leap seconds) to ensure that UTC does not deviate from UT1 by more than ±0.9 s. In 1999 through 2004, the difference TAI - UTC was 32 seconds. Time signal stations broadcast UTC, or a zone time that differs from UTC by an integral number of hours.


Regards.

Marco1971.

[tribe125]

Pretty thorough, Marco.

[Marco1971]

Thanks tribe125.

Marco1971.

[Adam in NYC]

The only G-Shocks (not counting other Casios) that can receive worldwide signals (US, UK, Germany & Japan x 2) are the GW-800, GW-810 & GW-9000 (solar atomic Mudman which is sold in Japan only).

[slayer9689]

yes, those are the correct models.

heres the link to my GW-800.

My new G-Shock GW-800

[GShocjdude]

The GW-800/810 are excellent multi-band watches. I'm in the UK and it picks up on either the UK signal or the one from Germany with equal ease (in fact, over the last few days it's syncing only with the Mainflingen signal.