Radio time signals

Times of transmission are given in Greenwich Mean Time (GMT) and Standard Time (S. Т.). When signals from Broadcasting Stations are used, it is necessary, if Summer Time is in force, to apply the appropriate difference to the Standard Time of the place in order to obtain the clock time of transmission.

. RADIO TIME SIGNALS. SERVICE DETAILS Great Britain

3029 Rugby.

Frequency: (A) (GBR) 16. (B) (GBR) 16.

(GIC) 8,640 (GIC) 8,640 (GKU2) 17,685 (GKU2) 17,685

Note: In the event of failure on (GBR), signals will be transmitted from (GBZ) on 19.6 kc/s.

(I) Ordinary Time Signals

Time: 10 h 00 m. 00 s. Frequency: (A).

18 00 00 (B)..

System: Series of 0.1 sec. dots at each second with a 0.6 sec. dash at each whole minute. The beginning of each dot or dash is the timing reference point.

Period of Transmission. From 5 m. 00 s. preceding the above times.

Preparatory Signals:

54 m. 00 s.—54 m. 45 s. "GBR GBR TIME" repeated four times followed by a continuous dash of 15 seconds¹ duration.

(II) Rhythmic Time Signals

Time: 10 h. 01 m. 00 s. Frequency: (A).

18 01 00 (B).

(After the ordinary time signals) System: Modified Rhythmic.

Period of Transmission: For 5 m. 00 s. from the above times.

Supplementary Signals: 06 m. 05 s.—06 m. 15s..., 10 s. dash (—).

South Africa

3405 Cape Town (ZSC)

Frequency: 500 A2.

Time- GM.T. 8 h. 00 m. 00 s. S. T. 10 h. 00 m. 00 s.

17 00 00 19 00 00

System: ONOGO (modified).

Source: Cape Observatory; automatic transmission.

Period of Transmission: From 3 m. 55 s. preceding the above times.

Preparatory Signals:

56 m. 05 s. —56 m. 50 s 0 ( )

repeated 5 times at 10-second intervals.

RADIO NAVIGATIONAL WARNINGS Regulations

Great Britain and Ireland

Warnings, containing information relating to the principal aids to navigation, derelicts, drifting mines, ice reports and other im- portant hydrographic matter, transmitted by radio telegraphy are preceded by the Safety Signal (TTT) repeated at short in- tervals 3 times on full power.

The navigational warning is transmitted one minute later.

Warnings transmitted by radiotelephony commence with the word "SAYCURITAY" and are broadcast first at conversational speed and then at dictation speed.

Radio navigational warnings and ice reports service details

Great Britain

5013 Seaforth (GLV)

Frequency: 1,845 1,650 A3

Time: 0803, 2003 (also at 0403 and 1603 when urgent).

Area Affected: Local.

Form of Message: Navigational Warnings.

Ireland

5031 Valencia (Valentia) (EJK)

Frequency: 500, 429 A2

Time: (A) 0818, 1218, 1618; (B) 0830, 2030 (also at 1230 and 1630 when urgent).

Area Affected: S. and S. W. coasts of Ireland and ap- proaches. ⁴

Form of Message: (A) Decca Warning Messages; (B) Navi­gational Warnings.

no

Ill

(Part A)

METEOROLOGICAL SERVICES, CODES, etc.

Contents

Preface

General Information Abbreviations

Call Signs

List of Meteorological Services. General Remarks, etc.

SHIPS' RADIO WEATHER REPORTS

British observing ships co-operating with the Meteorological Office, when in prescribed areas, transmit routine radio weather messages, addressed to Meteorological Centres, through detailed coast stations on appropriate waves as shown in the following table.

Reports should not be transmitted through other than the detailed Coast radio stations listed below. Standard times of obser­vation are 0000, 0600, 1200 and 1800 G.M.T.

RADIO WEATHER MESSAGES

Great Britain

GALE WARNING

1. Gale warnings (issued when winds of force 8 or above ^rare expected), will be broadcast from radio station, or stations, appropriate to the area within which the gale is expected. They will be broadcast on wave 500 kc/s immediately on receipt of the message at the station, but if received outside the periods 0800—0830, 1200—1230, 1600—1630 and 2000—?030, also at 18 min. past the hour during the next such period. Warning is preceded by the Safety Signal TTT, repeated at short intervals three times on full power. The warning follows one minute later.

2. Gale warnings are also broadcast by R/T on wave 1,650 kc/s at the first of the following watch-keeping times after receipt of message at the station: 0330, 0930, 1530 and 2030 G. M, T. Warnings are prefixed by the word "Saycuritay" (Securite) and are broadcast first at conversational speed and then repeated at dictation speed.

4008 Lands End (GLD)

/. Weather Bulletin

Time: 0848, 2048. Frequency: 500 kW., 438.5 kW.

Area Affected: South Western Area (Sole, Plymouth, Biscay, Finisterre).

Details of Messages and Procedure: See No. 4002, Section I.