World War II Navy Radio
Home | The Radioman's Job | My Receivers | Mill | Point to Point | My Transmitters | Remote Control | Radiotelephone | Portables | Test Equipment | Frequencies | Training | Procedures | Museum Activities | Museum Ships | On the Air Activities | Navy Television | Men Who Lived It | Resources | Hints and Kinks | Nancy(Infrared) | Wanted | Contact Me

NOTE - This is a re-creation of Rob Flory's original site which crashed some time ago - unfortunately some photos are still missing but most of the text is here - if you can help with any replacement photos, please send e-mail to Rob or to Nick K4NYW

Click here for Nick's 1950's-60's Navy Radio Pages -

Operating Procedures

VHF Radiotelephone Communications via TBS
VHF radio, which is limited to line-of-sight propagation, made it possible to communicate via radio under conditions when radio silence would have been necessary with HF radio.
The following excerpt from the Communications Instructions describes the conditions under which VHF radio may be used:

5305. Very-high-frequency (VHF) tactical radiotelephone circuits have proved their value in war. The following general rules are set forth for the guidance of responsible commanders in the use of such circuits in wartime:

a. They may be used for initial contact reports, emergency maneuvers, and the transmission of important information when visual means are prohibited or too slow.

b. Only a minimum of transmission should be permitted during darkness or reduced visibility.

c. Caution must be exercised in the use of plain language transmissions of vital importance which would be of value to the enemy if intercepted.

5306. Detailed instructions supplementing or modifying the foregoing general principles shall be issued by responsible commanders as appropriate and necessary, depending on the situation existing.

Note that under conditions of darkness or reduced visibility, when submarines or other vessels might be within range without being detected, use of VHF radio was discouraged.-RF

In Proudly We Served,  interviews with radiomen from the USS Mason talk about use of the TBS set to keep their convoy in order.


Excerpt from COMINCH P-013 (See Resources for link)
3412.  VHF radio channels are so essential for the efficient functioning of CIC that the benefits derived from their employment usually outweigh the loss of security.  For this reason, radio silence on these frequencies is usually ordered only under extreme conditions.  CIC OFFICER PERSONNEL SHOULD KNOW EXACTLY UNDER WHAT CONDITIONS AND BY WHOSE AUTHORITY RADIO SILENCE CAN BE BROKEN. Regardless of the condition of radio silence, all circuits should be set up for instant operation.

George Sallet, in his memoir, "The Six Long Years" refers to using both plain language and 4-letter code book over TBS.  He also refers to the code signal "
For more on the use of infrared communications by the US Navy in WWII, look at the following link.

Radio silence was the name of the game, as all transmissions by ships carried the risk of giving away the ship's position.  For this reason, the dominant method of radio communications was the "F" or "Fox" broadcast by shore stations.  These were sent by the giant shore stations like NAA, NSS, NPG on VLF, MF, and HF frequencies.  Much of an RMs watch in Radio Central was spent copying these messages which were sent in unintelligible 5-letter groups.  These groups are harder to copy than plain text, because you cannot fill in missing letters by recognizing a word.  A special typewriter, referred to as a "mill" was used to copy these messages.  See page called "Mill".
Message headers were encrypted using one system, and message content(body) using another more complex one.  The RMs passed all the messages they copied to the Communications Officer, who would decode the header to see if the message was for that ship, and if so, decode the body of the message.

Click below to read Robert E. Straub's description of radiotelegraph procedures he used as an RM aboard submarines. 

Z-Signals are Communications Procedure Signals used to send frequently-used messages expeditiously.  The following are excerpted from Army FM 24-10 "Joint Army and Navy Radio Procedure", prepared by the Joint Board 1940. These signals are totally different from the Z-signals used in the post-WII period, at least in the 60s, anyhow.  I have inserted a few examples to illustrate the use of signals. 

Communication Procedure Signals

4. Instructions for Operators.

A. These prosigs shall not be used unless required in the conduct of authorized communication and for station operation.

B. Plain language shall not be used with these signals except as prescribed and necessary for certain signal meanings.

C. IMI (?) May be used following a signal to indicate an interrogatory sense when a signal with the desired interrogatory meaning is not listed. The signal "ZZB" may be used preceding a signal to give a negative sense in case a signal with the desired negative meaning is not listed.

D. All blanks, except those within parentheses, must be filled in; use of blanks in parentheses is optional. Data for blanks shall appear in the same order as the blanks in the signal. Stations, addresses, and locations shall normally be indicated by call signs. Time shall be indicated by a four-numeral group. Dates may be indicated by numerals separated from the dispatch identification data by a slant (/) sign. Signals and numerals in signals may be separated by slant (/) signs to prevent misinterpretation.

ZAD Answer me on ____kc                                              NERK V K2WI ZAD 7045 K

ZCA Are you in communications with _____                NERK V K2WI ZCA ? NEPL K

ZCB I am in communications with ____                          K2WI V NERK ZCB NEPL K

ZCC Call me again at ____ (on ____kc)

ZCJ You (or____) were sending at the same time as ____

ZCM Collective callsign ____ for the present includes ____ ____ ____

ZCS Did you (or ____) hear____ at ____ ?

ZCV General call

ZEQ How is my note?

ZER Your note is 1-Good, 2-Poor, 3-Rising and Falling, 4-Overmodulated, 5-Undermodulated

ZES Your dots are ____ 1-Too Heavy, 2-Too Light

ZET Your transmitter is not keying properly.

ZFA I must shift to work another station (or _____)

ZFB Frequency _____ mc.

ZFC Frequency _____ mc.

ZFD Send Vís on this frequency (or _____ kc.)

ZFE I am (or _____ is) shifting to transmit on _____kc (at _____)

ZFF I am (or _____ is) shifting to receive on _____ kc (at _____ )

ZFG I am (or _____ is) able to receive on on _____ kc.

ZFH I am (or _____ is) able to transmit on on _____ kc.

ZFK Shift (or direct _____) to transmit and receive on _____kc.

ZFL What frequency are you (or is _____) using (to work _____ )?

ZFM How does my frequency check?

ZFN Your frequency is correct.

ZFO Your frequency is too high (or is _____ kc too high).

ZFP Your frequency is too low (or is _____ kc too low).

ZFQ Your frequency is _____ kc.

ZFR Adjust your transmitter frequency to zero beat with mine (or with _____ ).

ZFS Adjust your transmitter to proper frequency (or to _____ kc.).

ZFT Transmit on _____ kc. If you do not answer within 20 minutes I will shift back to present frequency.

ZFU I am going to transmit on _____ kc. If you do not answer within 20 minutes I will shift back to present frequency.

ZFV Measure your (or _____) frequency on this circuit (or on _____ kc.)

ZLA CW mode

ZMJ Following received from ____

ZOA Send at speed of ____ wpm

ZRC Act as relay between me (or ____) and ____

ZSA Can you receive ____ ? If so what is his readability?

ZSB I can receive ____ reability ____

1-Unreadable, 2-Poor, but readable, send plain lang. Twice, code unreadable, 3-Fair, send plain lang. Once slowly, code twice, 4-Readable, plain or code once, 5-Perfectly readable.

ZSC Your signals fade (from strength ____ to ____)

1-Very weak-hardly audible, 2-Moderately weak, 3-Medium strong, 4-Moderately strong, 5-Strong

ZSD Decrease strength of signals

ZSE Increase strength of signals

ZSF What is my signal strength?

ZSG What is my readability?


ZZA Stand by.

ZZB Negative, no, not.

ZZC Affirmative, yes.

ZZD Meaning of your (or _____ís) procedure signal (or procedure sign) is not understood.