페이지 이미지
PDF
ePub

TWO-ARM SEMAPHORE ALPHABET.

513. The semaphore alphabet is printed as the characters appear with the sender facing the receiver. Thus the character “B” is with the right arm extended horizontally.

514. Numbers shall always be spelled out.
515. The “break" and "answering” are shown in the plate.

516. Procedure signs ordinarily used are: Error.

E agitated.
Interrogatory.

INT.
Code follows.
MOTOR

BT
Signals follow.

IM. Number of words or groups.

GR (followed by number spelled out). End of word......

Break. End of sentence (full stop).

AAA (three a's). End of dispatch......

AR. Repeat all before word.

IMI break AB break (word). Repeat all after word.

IMI break AA break (word). Repeat word after word.

IMI break WA break (word). Received...

.R (used only when call flags are not

used. When call flags are used the hauling down of the call signifies

"dispatch received”). Move to your right.

MR 1 Move to your left.

ML1 Move up..

MU1 Move down..

MD 1

[graphic]

CALLS.

517. To call a ship or unit for a semaphore signal or dispatch

(a) By flag hoist. - Hoist the call of the ship or unit for whom the signal or dispatch is intended, “two-blocked” (unless it is necessary to make such a call while flag signals are displayed at the same yardarm, in which case the call may be hoisted at the dip).

The unit so addressed answers by hoisting the call of the calling ship over the answering pennant (1) at the "dip” as soon as seen and until ready to receive: (2, two-hlocked when ready to receive.

The attention'' sign should always be made by the transmitting ship when several signalmen are sending to a large number of ships in order that the receiving signalmen may select the sender offering the best background. It should also be used when transmitting to a single ship to give the receiver an opportunity to locate the sending signalman.

1 May be used in wigwag also.

14. THE SEMAPHORE ALPHABET CHAR- HAND CHAR- HAND CHAR- HAND CHAR- HAND

. ACTERS FLAGS ACTERS FLAGS ACTERS FLAGS ACTERS FLAGS

[graphic]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]

(6) Without flag hoist. --There is no equivalent for the call pennants in semaphore. When it is not practicable to call by flag hoist, and the "attention” sign is not sufficiently definite, three or four letters abbreviating the ship's name will be used as a call. To answer, the unit addressed makes the answering sign, and if that be not sufficiently definite, the three or four letters abbreviating the name of the ship answered.

SIGNALS BY SEMAPHORE.

518. The procedure prescribed for the transmission of signals by semaphore is as follows:

TRANSMITTING SHIP,

RECEIVING SHIP. (1) Makes call, either by flag hoist and (1) If the call be by flag hoist, answers attention; by "attention alone, or by call hy hoisting answering pennant under attention followed by letter or letters the call of the transmitting ship, at the abbreviating the name of the ship for dip as soon as seen and two-blocked when whom the signal is intended.

ready to receive and record. (2) When sending to one of two ships, (2) If the call be other than flag hoist, both of which have answered their calls makes the "answering sign,” followed if and which are approximately on the necessary by three or four letters abbresame bearing, makes the letters ab- viating the name of the transmitting ship. breviating the name of the receiving ship. This definitely signifies to which ship the signal is being sent. It may be omitted when there is no possibility of confusion or misunderstanding. (3) Makes break.

(3) (4) Makes signal sign (IM). (5) Makes break.

(5) (6) Makes signal. The names of the (6) When the call and answer is by flags or letters and numerals are to be flag hoist the answering pennant is to be spelled out. The names of flags, etc., dipped immediately a word or sign is are separated by the break; complete missed. If the call be other than by flag signals are separated by the full stop. hoist, makes repeat (IMI). (7) Makes break.

(7) (8) Makes “finale” sign (AR).

(8) (9) Makes break, and waits for re- (9) Makes received sign R if signal is ceiving ship to make IMI, J, or R. understood.

(10) If a tactical signal makes IX IX (10) Repeats IX and hauls down the several times, followed by the finale answering hoist when the transmitting sign AR, and hauls down call (if used), ship hauls down the call. as a final signal of execution. If a nontactical signal, no execute is required, makes the "finale” sign AR and hauls down call, if used.

[ocr errors]

519. Any desired degree of assurance that the signal has been received, may be attained by the use of prescribed procedure signs. Thus if the call is followed by

(a) “G,” the receiving unit will repeat back.
(6) “Y,the receiving unit will acknowledge.

C) "Gand "Y,''the receiving unit will repeat back and acknowledge.

DISPATCHES BY SEMAPHORE. 520. The procedure signs prescribed for Morse are to be used in semaphore when required. When used, their position in the dispatch corresponds to their position when used in systems employing Morse.

521. The procedure prescribed for the transmission of dispatches by semaphore is as follows: TRANSMITTING SHIP.

RECEIVING SHIP. (1) Makes call, either by flag hoist and (1) If the call be by flag hoist, answers attention, by "attention alone, or by call by hoisting answering pennant under attention followed by letter or letters the call of the transmitting ship at the abbreviating the name of the ship for dip, as soon as seen, and two-blocked whom the dispatch is intended.

when ready to receive and record.

If the call be other than flag hoist, makes the "answering" sign, followed, if necessary, by three or four letters abbreviating the name of the transmitting

ship. (2) When confusion might arise as to (2) which ship the dispatch is being transmitted, makes the letters abbreviating the name of the receiving ship. When there is no possibility of confusion, this may be omitted. (3) Makes break.

(3) (4) Makes GR followed by number of groups or words. (5) Makes break.

(5) (6) Makes BT followed by “break” if (6) text is in code.

(7) Proceeds with text of dispatch, all (7) When the call and answer is by numbers being spelled out.

flag hoist, the answering pennant is to be dipped immediately a word or sign is missed. If the call be other than by

flag hoist, makes repeat (IMI). (8) Makes break.

(8) (9) Makes AR, and háuls down the (9) Acknowledges the receipt of the flag call if used.

dispatch (a), if the call and the answer be by flag hoist, by hauling down the answering hoist when the transmitting ship hauls down the call; (b) if the call and answer be other than by flag, makes

“R." 13050—20- -14

522. The failure to receive a word or sign is indicated:

(1) If the call and answer be by flag hoist, by the receiving unit dipping the answering pennant.

(2) If the call and answer be other than by flag hoist, by the receiving unit making the repeat sign IMI.

523. On receipt of the dispatch if the call and answer be by flag hoist, the receiving unit hauls down the answering hoist.

524. If during the sending of the dispatch, the receiving unit fails to receive any part of it for any reason such as sender becoming obscured by smoke, etc., the receiving unit uld dip the answering pennant. The sending ship should then dip the call. When the receiving unit is again ready to receive, she should two-block the answering pennant. The sending ship should then two-block the call and proceed with the dispatch, starting with and repeating the last two or three words transmitted before the answering pennant was dipped.

525. If more than the last word or sign is required the appropriate procedure sign for repeating the required portion should be made.

WIGWAG. 526. Wigwag employs the International Morse Alphabet, numerals and special Morse signs. A motion through an arc of 90° to the

sender's right represents a “dot," and a similar motion to the left a “dash.” The only signs peculiar to wigwag are:

(1) The attention" sign, i. e., the flag waved back and forward overhead and

(2) The“ break” sign, i. e., a motion to the front.

576. A hand flag, a hand light, or a searchlight beam is used. The sender should face the receiver squarely. The motions for the dot and dash should be made at right angles to the line of transmission, and forthe'break” from the vertical position through an arc 'of 135° in the direction of the line of transmission. In order to

keep the flag fully exposed the point of the staff should be made to describe an elongated figure 8. In case a hand light is used, it is desirable to have a reference light at the

DASH

« 이전계속 »