Goto Section: 11.32 | 11.34 | Table of Contents

FCC 11.33
Revised as of October 1, 2010
Goto Year:2009 | 2011
  §  11.33   EAS Decoder.

   (a) An EAS Decoder must at a minimum be capable of decoding the EAS
   protocol described in § 11.31, provide the EAS monitoring functions
   described in § 11.52, and the following minimum specifications:

   (1) Inputs. Decoders must have the capability to receive at least 2
   audio inputs from EAS monitoring assignments, and one data input
   (RS-232C with standard protocol and 1200 baud rate). The data input may
   be used to monitor other communications modes such as Radio Broadcast
   Data System (RBDS), NWR, satellite, public switched telephone network,
   or any other source that uses the EAS protocol.

   (2) Valid codes. There must be a means to determine if valid EAS header
   codes are received and to determine if preselected header codes are

   (3) Storage. Decoders must provide the means to:

   (i) Record and store, either internally or externally, at least two
   minutes of audio or text messages. A decoder manufactured without an
   internal means to record and store audio or text must be equipped with
   a means (such as an audio or digital jack connection) to couple to an
   external recording and storing device.

   (ii) Store at least ten preselected event and originator header codes,
   in addition to the seven mandatory event/originator codes for tests and
   national activations, and store any preselected location codes for
   comparison with incoming header codes. A non-preselected header code
   that is manually transmitted must be stored for comparison with later
   incoming header codes. The header codes of the last ten received valid
   messages which still have valid time periods must be stored for
   comparison with the incoming valid header codes for later messages.
   These last received header codes will be deleted from storage as their
   valid time periods expire.

   (4) Display and logging. A visual message shall be developed from any
   valid header codes for tests and national activations and any
   preselected header codes received. The message shall include the
   Originator, Event, Location, the valid time period of the message and
   the local time the message was transmitted. The message shall be in the
   primary language of the EAS Participant and be fully displayed on the
   decoder and readable in normal light and darkness. All existing and new
   models of EAS decoders manufactured after August 1, 2003 must provide a
   means to permit the selective display and logging of EAS messages
   containing header codes for state and local EAS events. Effective May
   16, 2002, analog radio and television broadcast stations, analog cable
   systems and wireless cable systems may upgrade their decoders on an
   optional basis to include a selective display and logging capability
   for EAS messages containing header codes for state and local events.
   EAS Participants that install or replace their decoders after February
   1, 2004 must install decoders that provide a means to permit the
   selective display and logging of EAS messages containing header codes
   for state and local EAS events.

   (5) Indicators. EAS decoders must have a distinct and separate aural or
   visible means to indicate when any of the following conditions occurs:

   (i) Any valid EAS header codes are received as specified in
   § 11.33(a)(10).

   (ii) Preprogrammed header codes, such as those selected in accordance
   with § 11.52(d)(2) are received.

   (iii) A signal is present at each audio input that is specified in
   § 11.33(a)(1).

   (6) Program Data Retention. The program data must be retained even with
   power removed.

   (7) Outputs. Decoders shall have the following outputs: a data port or
   ports (RS-232C with standard protocol and 1200 baud rate) where
   received valid EAS header codes and received preselected header codes
   are available; one audio port that is capable of monitoring each
   decoder audio input; and, an internal speaker to enable personnel to
   hear audio from each input.

   (8) Decoder Programming. Access to decoder programming shall be
   protected by a lock or other security measures and be configured so
   that authorized personnel can readily select and program the EAS
   Decoder with preselected Originator, Event and Location codes for
   either manual or automatic operation.

   (9) Reset. There shall be a method to automatically or manually reset
   the decoder to the normal monitoring condition. Operators shall be able
   to select a time interval, not less than two minutes, in which the
   decoder would automatically reset if it received an EAS header code but
   not an end-of-message (EOM) code. Messages received with the EAN Event
   codes shall disable the reset function so that lengthy audio messages
   can be handled. The last message received with valid header codes shall
   be displayed as required by paragraph (a)(4) of this section before the
   decoder is reset.

   (10) Message Validity. An EAS Decoder must provide error detection and
   validation of the header codes of each message to ascertain if the
   message is valid. Header code comparisons may be accomplished through
   the use of a bit-by-bit compare or any other error detection and
   validation protocol. A header code must only be considered valid when
   two of the three headers match exactly. Duplicate messages must not be
   relayed automatically.

   (11) A header code with the EAN Event code specified in § 11.31(c) that
   is received through any of the audio inputs must override all other

   (b) Attention Signal. EAS Decoders shall have detection and activation
   circuitry that will demute a receiver upon detection of the two audio
   tones of 853 Hz and 960 Hz. To prevent false responses, decoders
   designed to use the two tones for receiver demuting shall comply with
   the following:

   (1) Time Delay. A minimum time delay of 8 but not more than 16 seconds
   of tone reception shall be incorporated into the demuting or activation
   process to insure that the tones will be audible for a period of at
   least 4 seconds. After July 1, 1995, the time delay shall be 3-4

   (2) Operation Bandwidth. The decoder circuitry shall not respond to
   tones which vary more than +-5 Hz from each of the frequencies, 853 Hz
   and 960 Hz.

   (3) Reset Ability. The decoder shall have a means to manually or
   automatically reset the associated broadcast receiver to a muted state.

   (c) Decoders shall be capable of operation within the tolerances
   specified in this section as well as those in § 11.32 (b), (c) and (d).

   [ 59 FR 67092 , Dec. 28, 1994, as amended at  60 FR 55999 , Nov. 6, 1995;
    67 FR 18510 , Apr. 16, 2002;  70 FR 71033 , Nov. 25, 2005]

Goto Section: 11.32 | 11.34

Goto Year: 2009 | 2011
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