The Military => The Military: Facts, Procedures, Drills, Tactics, Traditions, Q&A => Topic started by: Rattler on 15 September 2009, 22:51:53



Title: NATO Z-Codes
Post by: Rattler on 15 September 2009, 22:51:53
Z-Codes are three digit codes formed of letters (and always start with "Z", hence the name) to facilitate quick communications, especially when using morse code (and are used similarily to the civil Q-Codes). They are called "Operating Signals".

The Z-Code was originally developed as a service code by Cable & Wireless Ltd. for usage in the commercial communications business. NATO military Z-signals are completely different from the old Cable & Wireless codes.

The NATO military Z-signals, ZAA-ZXZ, are defined in ACP 131 and are in use by the whole Alliance. The series ZYA-ZZZ is reserved for the temporary or permanent assignment of meanings on an intra-military basis by any nation, service or command (and hence can differ for every nation).

I have condensed the AACP 131 manual into just the basic instructions and added a facsimile list of the ZAA-ZXZ Operating Signals, when you have gone through them you will hopefully understand the following (solution at the bottom of this post):

ZUC rattler users ZUI read ZDA ZCZ1 ZLA1 INT ZBK ZAL 0500Z sleep ZTL

Rattler, out.


How to use them


a. Action

Z signals ordering or indicating that an action is to be taken (a change of frequency, for example) will be answered before the action is taken, unless the "Broadcast" method is used or the station ordering or indicating the action has indicated that an answer is not required.


b. Affirmatives or Negatives.

Operating signals, as appropriate, will be used by allied  military stations to convey an affirmative or negative sense to allied military stations by using the appropriate Z signal:

Examples (of replies):

ZOE Means: (Yes) Give me your message. I will dispose of it.

NOTE: In addition to the above, replies to questions from military stations may be made by using ZUE meaning Affirmative (Yes) or ZUG meaning Negative (No).


c. Blank Spaces.

Blank spaces in the meanings of Z signals must be completed, in the order in which they appear; however, blank spaces enclosed in parentheses normally will be completed on an optional basis only.

Examples:

(1) ZOH Bf2 350  means: "Send message for Bf2 on 350 kHz". (The meaning assigned to ZOE is  "Send message for ... on ... kHz"; therefore, as these blank spaces are not included in parentheses, all are completed, in the order in which they appear).

(2) ZKO BG2 means: "I have handed over guard to BG2". (The meaning assigned to ZKO is "I have handed over guard (to...) (on...kHz (or MHz)) (serial number of last message received was...)"; however, in this example, the user elected to complete only one of the blank spaces enclosed in parentheses, the first one).


d. Call Signs

Normally call signs will follow the Z signal to which they refer; however, they also may precede the operating signal for separation or clarity.


e. Frequencies

(1) When the meaning of a Z signal includes the expression "on... kHz (or MHz)", the figures used alone (not supplemented by an abbreviation) always will indicate the frequency in kilohertz. To indicate the frequency in megahertz, the figures will be supplemented by the abbreviation "MHz".

(2) Provided that no confusion can arise, in those Z signals whose meaning includes the expression "on...kHz (or MHz)", the circuit designator or other disguised reference, if available, will be used in place of the actual frequency.

(3) Although not provided for in the meaning of a Z signal, a frequency may be used with any such operating signal by adding figures and the appropriate abbreviation ("kHz" or "MHz").


f. Numbered Alternates

Z signals with numbered alternate meanings will be followed, without spacing, by the appropriate number to indicate the meaning intended.

Example:

ZAP5 means: Work single sideband. (as ZAP has the following numbered alternate meanings - "Work...(1. simplex; 2. duplex; 3. diplex;
4. multiplex; 5. single sideband).")


g. Plain Language

Plain unabbreviated language is authorized for use to complete or amplify the meaning of operating signals only when no other approved method will do.


h. Questions

Operating signals, as appropriate, will be used by allied military stations to ask questions if military stations, by inserting the prosign INT before the Z signal to which it refers.

Examples:

INT ZDJ means: How many groups does your message contain?


i. Security

Operating signals possess no security. They must be regarded as the equivalent of plain language.


j. Separation

The separative sign (prosign II, written as a short dash) may be used to separate Z signals when desired.


k. Time Groups

Time groups (including date-time groups) used with Z signals always will be followed, without spacing, by a time zone suffix letter. Although not provided for in the meaning of a Z signal, a time group (including date-time group) may be used with any such operating signal.


l. Units of Measurement

When units of measurement are desired for use which differ from those in the meaning of an operating signal, an appropriate abbreviation will be used.


List of the Z Operating Signals as used by NATO:


(http://www.warandtactics.com/z_codes/z_codes1.gif)

(http://www.warandtactics.com/z_codes/z_codes2.gif)

(http://www.warandtactics.com/z_codes/z_codes3.gif)

(http://www.warandtactics.com/z_codes/z_codes4.gif)

(http://www.warandtactics.com/z_codes/z_codes5.gif)

(http://www.warandtactics.com/z_codes/z_codes6.gif)

(http://www.warandtactics.com/z_codes/z_codes7.gif)

(http://www.warandtactics.com/z_codes/z_codes8.gif)

(http://www.warandtactics.com/z_codes/z_codes9.gif)

(http://www.warandtactics.com/z_codes/z_codes10.gif)

(http://www.warandtactics.com/z_codes/z_codes11.gif)

(http://www.warandtactics.com/z_codes/z_codes12.gif)

(http://www.warandtactics.com/z_codes/z_codes13.gif)

(http://www.warandtactics.com/z_codes/z_codes14.gif)

(http://www.warandtactics.com/z_codes/z_codes15.gif)

(http://www.warandtactics.com/z_codes/z_codes16.gif)

(http://www.warandtactics.com/z_codes/z_codes17.gif)

(http://www.warandtactics.com/z_codes/z_codes18.gif)

(http://www.warandtactics.com/z_codes/z_codes19.gif)

(http://www.warandtactics.com/z_codes/z_codes20.gif)

(http://www.warandtactics.com/z_codes/z_codes21.gif)

(http://www.warandtactics.com/z_codes/z_codes22.gif)

(http://www.warandtactics.com/z_codes/z_codes23.gif)

(http://www.warandtactics.com/z_codes/z_codes24.gif)

(http://www.warandtactics.com/z_codes/z_codes25.gif)

(http://www.warandtactics.com/z_codes/z_codes26.gif)

(http://www.warandtactics.com/z_codes/z_codes27.gif)

(http://www.warandtactics.com/z_codes/z_codes28.gif)

(http://www.warandtactics.com/z_codes/z_codes29.gif)

(http://www.warandtactics.com/z_codes/z_codes30.gif)

(http://www.warandtactics.com/z_codes/z_codes31.gif)

(http://www.warandtactics.com/z_codes/z_codes32.gif)

(http://www.warandtactics.com/z_codes/z_codes33.gif)

(http://www.warandtactics.com/z_codes/z_codes34.gif)

(http://www.warandtactics.com/z_codes/z_codes35.gif)

Solution to the coded message from above:

ZUC rattler users ZUI read ZDA ZCZ1 ZLA1 INT ZBK ZAL 0500Z sleep ZTL

would translate to:

From Rattler to users. Your attention is invited to read. I have a message for you. Coded. I have pictures of the following type to transmit: Photographs. Are you receiving my traffic clear? I am closing down until 0500Z due to sleep. I am about to disconnect.


Title: Re: NATO Z-Codes
Post by: Jilly on 16 September 2009, 03:38:13
Where did you learn all this stuff, Rattler?


Title: Re: NATO Z-Codes
Post by: Rattler on 16 September 2009, 13:12:15
8 yrs soldiering, and 5+ of it in signals... :)

Rattler


Title: Re: NATO Z-Codes
Post by: Jilly on 16 September 2009, 16:09:57
Amazing,  what's it like to be brainy?   smallclap


Title: Re: NATO Z-Codes
Post by: Rattler on 16 September 2009, 20:30:53
well, my neck is a bit bent with all the weight to support, but apart from that... :)

Rattler


Title: Re: NATO Z-Codes
Post by: Jilly on 16 September 2009, 20:41:38
 ;D


Title: Re: NATO Z-Codes
Post by: the_13th_redneck on 20 September 2009, 12:54:29
Amazing stuff!
So it was used to use morse code and other such signals to send long messages quickly.
Genius!


Title: Re: NATO Z-Codes
Post by: Rattler on 20 September 2009, 16:24:56
Amazing stuff!
So it was used to use morse code and other such signals to send long messages quickly.
Genius!

There was a solid tactical requirement behind it: During Cold War (talking ยด70s here) the typical time needed for Soviet forces to locate (triangulate) a transmitter was between 6-15 seconds fully automated on their territory, after that (if e.g. the transmitting unit was a deep recon uit behind enmy lines) you would have the hunter groups on your back.

Reducing message length was obviously essential, it was done by employing codes and later also by mechanically (tape speed) or electronically compressing (upspeeding) the morse code so that it could be sent in 5 seconds bursts (and after transmit the unit in the example mentioned above would relocate the hell out of dodge).

Rattler


Title: Re: NATO Z-Codes
Post by: the_13th_redneck on 20 September 2009, 16:48:11
So do they still use these?  Because I am completely unfamiliar with them.


Title: Re: NATO Z-Codes
Post by: Rattler on 21 September 2009, 10:28:28
So do they still use these?  Because I am completely unfamiliar with them.


I do not know whether they are still in active use (with satlink comms and what is more), but they still are trained: Continuous Wave operators still need to be able to read 20 WPM (Words Per Minute), also, it was shown in recent contests that morse code beats SMS anytime as far as speed is concerned (hammering the morse key vs. typing SMS on a mobile: Top contestant managed to hammer out 40 WPM, SMS didnt make more than 21).

Quote
From Wikipedia: Operators skilled in Morse code can often understand ("copy") code in their heads at rates in excess of 40 WPM. International contests in code copying are still occasionally held. In July 1939 at a contest in Asheville, NC in the United States Ted R. McElroy set a still-standing record for Morse copying, 75.2 WPM.

In his online book on high speed sending, William Pierpont N0HFF notes some operators may have passed 100 WPM. By this time they are "hearing" phrases and sentences rather than words.

The fastest speed ever sent by a straight key was achieved in 1942 by Harry Turner W9YZE (d. 1992) who reached 45 WPM in a demonstration at a U.S. Army base.


Where the "Z" codes (and the civilian based "Q" codes) are still widely used are on sea and for alternative comms methods in case channels fail:

- Ships light signalling and flag signalling uses them, they are trained and currently in use in times of EMCON situations.

- Semaphores transmissions also use them still

Last, as military teletypers were based on the system, they are integrated in the modern software there.

In general, here is todays layout:

Applicability of codes by type of emission

    * Civilian radio continuous wave (CW): Q codes.
    * Military radio continuous wave (CW): Q codes and Z codes.
    * Civilian shipboard signal lamp: Q codes.
    * Military shipboard signal lamp: Q codes and Z codes.
    * Military Flag semaphore: Q codes and Z codes.
    * Military teletype: Z codes used as routers in message header.

FWIW,

Rattler