"Z" is used in this case to signify to B 25 that the dispatch is addressed to her, and the "B 25 V B 34" signifies to B 25 that it is "from" B 34 and that B 25 does not have to pass the dispatch further, as it is addressed to her.

"V."

442. The letter "V" used between calls signifies "From 443. The letter "V" is used in this connection only in the case of dispatches in which the letters "T" or "Z" are used in the preamble to show the addressee from whom the dispatch has come (see example under T, Art. 441), and in the case of dispatches repeated back when requested by a ship subsequent to the time at which the dispatch was originally sent. (See example (a), Art. 415.)

"W."

444. The letter "W" used by itself signifies "Am unable to read your message. If signaling by flashing light, signifies light not properly trained or light burning badly; if by semaphore or flag waving, poor back ground or interference, such as smoke, etc. 445. This is to be made by any receiving ship at any stage of the transmitting, if required.

Example (a).

B 34 is sending a dispatch by searchlight by day to B 25.

If due to bad training of the light or bad focus, B 25 finds it difficult to read the dispatch, she informs B 34 of this by making "W", repeating it as necessary until B 34 corrects the fault. B 34 should then repeat the whole dispatch, unless B 25 has received part of the dispatch before it becomes necessary to make "W”, in which case she should request repetition of so much of it as may be necessary by the procedure sign IMI (see art. 383), calling B 34 if necessary. "Y."

446. The letter "Y" used as a dispatch in itself signifies "Acknowledge."

447. The letter "Y" in the prefix directs the addressee to acknowledge the dispatch.

Example (a).

B 34 has the code dispatch "KUBO-ABYZ-1020" for B 25. The dispatch is to be acknowledged.

B 34 makes:

B 25

B 25 makes:
R.

B 34 II Y II GR 3 BT KUBO II ABYZ II 1020 AR

448. The letter "Y" followed by a four-figure numeral group (time of origin or by two four-figure groups separated by "break") "office reference number and date group" and "time of origin") signifies "Dispatch- understood."

Example (a).

B 25 having received the dispatch shown in Art. 447, example (a), and the dispatch having been understood by the captain, the latter directs this fact to be reported to B 34.

449. It must be distinctly understood that a dispatch is not to be acknowledged until it is understood by the addressee, and that the authority of the commanding officer, or other competent authority is required before the acknowledgment is made.

450. The "interrogatory" sign (INT) used in conjunction with the letter "Y" and a time of origin or office reference number and date group, signifies "Is dispatch referenced understood?”

451. The letter "Y" used in conjunction with the "interrogatory" sign in this manner may be used either: (a) To hasten the acknowledgment for a prior dispatch which was prefixed "Acknowledge" or (b) to call for an acknowledgment for a prior dispatch which was not originally prefixed "Acknowledge."

Example (a).

B 34 wishes B 25 to acknowledge B 34's dispatch timed 1020. (1) The dispatch was not originally prefixed "Acknowledge. (2) The dispatch was prefixed "Acknowledge," but B 25 has not yet acknowledged.

In either case B 34 makes to B 25:

452. The "interrogatory" sign in conjunction with the letter "Y" must not be used without the authority of a responsible officer. NOTE.-Attention is called to the fact that dispatches may also be acknowledged by the signal "F with four or eight numerals" either by flag hoist or other method. (For this signal see Signal Book.) The distinction between acknowledging by "F and numerals" used as a signal, and "Y" used as a procedure sign, must be carefully observed.

to

453. The letter "Z" used in the preamble signifies "addressed

454. It is used only in dispatches that have been transmitted from the originator to the addressee by an intermediate ship and then only by the relaying ship to the addressee to show the latter that the dispatch is a relayed one and is addressed to her.

Example (a).

B 34 has a dispatch for B 25 and wishes to send it to B 36 for retransmission to B 25.

B 34 makes:

B 36

В 34 IIT II B 25 V B 34 II GR 10 II Report probable time at which anchor will be clear 0935 AR

B 36 then transmits the dispatch to B 25 as follows:

B 25

В 36 II Z II B 25 V B 34 II GR 10 II etc. This procedure indicates to B 25 that the dispatch is addressed to her and is from B 34.

455. It is to be noted that when B 34 is sending to B 36, the procedure sign "T" is used which directs B 36 to relay the dispatch which follows to B 25. When B 36 retransmits to B 25, the "T" changes to "Z," for the dispatch is addressed to B 25, and is not to

be transmitted further.

13050-20-13

Transmission of Signals and Dispatches by Methods Other than by Flags.

DEFINITIONS.

456. The definitions of the following terms used throughout these instructions are to be noted:

Acknowledgment.-A dispatch (or signal) is acknowledged by a separate dispatch from the addressee informing the originator that his dispatch (or signal) has been received and is understood. This separate dispatch is an "acknowledgment."

Addressee.-Addressee is the authority to whom signal or dispatch

is addressed.

Addressed to. This term denotes that the authority indicated is required to take all necessary action to carry out the purport of the signal or dispatch.

Dispatch. A dispatch is any communication other than a signal or letter, regardless of the method of transmission.

Dip. Signals are said to be at the dip when the top of the top flag of the signal is about 8 feet from being two-blocked (i. e., about 8 feet from the yardarm).

Originator.-Originator is the authority who orders a signal or dispatch to be sent.

Procedure. This term denotes the rules drawn up for the conduct of transmission of signals and dispatches.

Procedure sign.-Procedure sign is a sign designed for facilitating the conduct of transmission.

Receiving ship.-Receiving ship is the ship by which a signal or dispatch is actually being read.

Reply.-Reply is a signal or dispatch originating out of, referring to or replying to a question asked in a prior signal or dispatch.

Signal. A signal is an arbitrary combination of letters, numbers, and special signs, the meaning of which is to be found in a Signal Book. Signals are distinguished by that term from communications spelled out in plain language or sent in code, which are classified as "dispatches." Throughout this book the term "general signal" refers to those signals which are to be obeyed by all ships within signal distance. It does not refer to the publication in which signals may be listed.

Transmitting ship.-Transmitting ship is the ship by which a dispatch is actually being made.

PARTS OF A SIGNAL OR DISPATCH.

457. With any system using the Morse code, the full signification of the communication is not apparent until the communication is complete; that is, the addressee, on seeing or hearing his call, has no knowledge of what is to follow. Not only must the signal or dispatch be transmitted and received part by part according to a prescribed order, but special signs are necessary for clearness and precision. 458. In general, a signal or a dispatch consists of the following: (1) The heading, consisting of

(a) The call (always appears).

(b) The preamble.]

(c) The address.

(d) The prefix.

(May or may not appear.)

(2) The office reference number and date group (may or may not appear in dispatches, never appears in signals).

(3) The text (always appears).

(4) The time of origin number (usually appears in official dispatches, does not usually appear in signals).

THE HEADING.

459. (a) The call.-The call consists of the call(s) of the receiving unit(s) and the call of the transmitting unit. In establishing communication, the transmitting ship calls the receiving unit by making the call of that unit. The latter answers by repeating the call as made by the transmitting ship. The transmitting unit then sends her own call, which is repeated by the receiving unit(s).

(b) The preamble. The preamble consists of procedure signs and, if necessary, the calls denoting the route of the signal or dispatch. (c) The address.--The address consists of the call of the addressee and the call of the originator separated by "V" (from).

(d) The prefix.-The prefix consists of procedure signs denoting the type of the signal or dispatch and any instructions regarding the signal or dispatch itself. It also includes the number of groups or words in the text, preceded by the procedure sign “GR.” The position of the group sign is at the end of the prefix.

460. The heading is separated from the text by the procedure sign: (1) II if the text consists of plain language.

(2) BT if the text consists of code.

(3) IM (the signal sign) if the text consists of a signal or signals.