need to know, but which was not an addressee of the original  message.  This  process  is  called  message readdressal.  The  originator  or  action  addressee  of  a message  may  readdress  that  message  to  another  activity for  action  or  info.  Information  addressees  may readdress a message to another activity for information only. Separate readdressal requests must be made for each message and/or section being readdressed. Figure 1-15 is an example of a message readdressal. The MTF editor program will provide all required fields. Reduction in Transmission of Message Traffic (MINIMIZE) When an actual or simulated emergency arises or is anticipated, it may become necessary to reduce the volume of record and/or voice communications by imposing MINIMIZE on all military circuits. This action is designed to reduce message traffic during high tempo  operations.  Only  traffic  directly  related  to mission accomplishment or safety of life is considered essential  and  therefore  appropriate  for  electronic transmission. Even high precedence messages that do not meet this criteria cannot be transmitted during MINIMIZE. In most cases, MINIMIZE is imposed only for a particular geographical region or operating area. Certain METOC-related messages, such as high wind  and  high  seas  warnings,  are  exempt  from MINIMIZE as per NAVMETOCCOMINST 3140.1. Weather   and   oceanographic   observations   are considered  significant  and  should  be  transmitted  during MINIMIZE  when  any  conditions  listed  in  table  1-3 exist. Table 1-3.—Weather and Oceanographic Conditions Exempting Observation From MINIMIZE WEATHER  OR  OCEANOGRAPHIC CONDITION Wind  speeds in excess of 34 knots. Sea height of 12 feet or greater. Moderate  or heavy precipitation. Pressure change of 3 hPa or greater within the past 3 hours. Visibility less than 1 mile. Oceanographic  observations  as  dictated  by  current operations. Volcanic activity producing volcanic ash. REVIEW QUESTIONS Q25.    Which subsystem of AUTODIN acts as a security screen for incoming messages? Q26.    Which computer software is used by the Navy to format electronic messages? Q27.  What  publication  outlines  procedures  for formatting USMTF messages? Q28.  Where  can  a  listing  of  METOC-related Collective  Address  Designators  (CADs)  be found? Q29.    What is the fastest way to obtain correct Plain Language  Address  (PLA)  information? Q30. When is the set identifier "NARR/" used in a GENADMIN message? Q31.  Declassification  dates  are  valid  for  what maximum period? Q32.    What are the two essential considerations for sending  electronic  message  traffic  during MINIMIZE  conditions? PMSV RADIO COMMUNICATIONS LEARNING OBJECTIVES: Recognize the purpose of PSMV. Discuss proper PMSV radio operation procedures and proper voice radio communications  protocol. Pilot-to-Meteorological Service (PMSV) radio transceivers  are  found  at  most  military  aviation  weather offices ashore. PMSV is used to relay meteorological information  between  airfield  weather  offices  and aircraft pilots. Operating frequencies for each site are assigned by the Federal Communications Commission (FCC). PMSV transceivers operate in the VHF and UHF frequency ranges, with assigned frequencies generally around 200 to 400 MHz. The frequencies for PMSV  services  are  listed  in  the  DOD  Flight Information Publications (Enroute), IFR Supplements, commonly called DOD FLIP IFR Supplements.   If an airfield has a PMSV radio, the frequency is listed for the airfield   as   the   METRO   frequency,   under   the Communications heading. The radio transceivers are set to operate only on the assigned frequency. Normally only the amplifier unit with  an  audio  speaker  and  an  attached  push-to-talk microphone is located within the weather office. The actual  transmitter,  receiver,  and  antenna  assemblies  are 1-25