Goto Section: 11.32 | 11.34 | Table of Contents
Revised as of October 1, 2010
Goto Year:2009 |
§ 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
(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
(6) Program Data Retention. The program data must be retained even with
(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
(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
(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 |
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