UT12-000 Universal Encoder/Decoder
SM40 Installation and Operation Manual
May 15, 2012 Rev: 5.00
Page 3-10
ENG-FORM: 806-0100.DOTX
CONFIDENTIAL AND PROPRIETARY TO ANODYNE ELECTRONICS MANUFACTURING CORP.
3.5 Reception
(Decoding)
3.5.1
Receiving Regular Call
LAM Network:
When receiving sequences on the LAM network, there will usually be two sequences. The first is
the ID sequence of the unit being called and the second is the ID sequence of the unit calling.
The UT12 will examine the sequence, and if it matches its own ID sequence, will gate head
phone audio, and trigger an audible warning. The UT12 will transmit its own ID sequence 750 ±
50 ms after the last received tone of the ID sequence. The control head will display
–
CALL - :
XXXXX
where
XXXXX
is the calling unit’s ID sequence if received. If no calling unit’s ID is
received the control head will display
–
CALL -: NO ID
. Note that as general protocol the first
sequence transmitted is that of the unit being called, however, if
ANY
of the received sequences
matches the UT1
2’s ID sequence, it will react as described above.
The audible warning is initiated by the UT12 pulling the alert key line low, to produce an externally
generated alert tone.
AFN Network:
When receiving sequences on the AFN network, there will usually be one sequence - that of the
unit being called. The UT12 will behave as described above.
The UT12’s reply ID sequence is sent 750 ± 50ms after the last tone received. This response will
use a short (100 ms) first tone when operating on LAM network and a long (700 ms) first tone
when on the AFN network.
3.5.2
Receiving Group Call:
If the received sequence matches the UT12’s ID sequence, but with the last one, two or three tones as
zeros (i.e.: UUUU0 or UUU00 or UU000), the call will be classified as a group call. The UT12 will react as
it would for a regular call, except no reply ID sequence will be sent.
GroupCALL XXXXX
will be
displayed on the control head. LAM and AFN operate identically in this respect.
3.5.3
Receiving Alarm Call:
LAM Network:
If
the received sequence matches the UT12’s pre
-programmed community code with the last
three tones being 000 or 400 (i.e.: CC000 or CC400) the call will be classified as an alarm call.
The UT12 response the same as for a group call, except that
**ALARM**:XXXXX
will be
displayed on the control head.
AFN Network:
There is no alarm call on the AFN Network; however, if the UT12 receives an alarm call while on
an AFN frequency, it will operate the same as on the LAM network.
