Instruction Manual - DECA | Diving Equipment Company of America

THEORY OF OPERATION
OPTION /26 HELIUM UNSCRAMBLER 7.5
The Helium Speech Unscrambler card receives the diver’s audio signal from mixer U6A and
corrects for the effect of helium breathing gas on the divers voice. The corrected audio is then fed
back to the mixer U6B.
The technique used by the Amron helium unscrambler, is to convert the audio analog information
to digital, store the digital information, and recombine the digital information so as to reconstruct
the audio without the frequency shift caused by the helium gas.
OPTION /28FDW WIRELESS TENDER 7.6
The wireless tender option uses a transceiver to relay audio from a remote unit to the divers. The
wireless tender is a full duplex communication for Simulcom (four-wire). Amron’s Full Duplex
(Simulcom) Wireless Tender is designed for the top-side tender to communicate to divers with
hands-free operation and no required buttons to push.
In addition to the remote unit, there is a master transceiver inside the communicator. Both channel
selector switch (A&B) and dipswitches (located under the battery) accommodate 40 different
channels with operating frequency range 902-928MHz. Manufacture sets both wireless
communicator and wireless remote module to work on Channel A with dip-switches setting
1,1,1,1,0,0,0,0 (1 is ON). In order to change channel of operation, it is required to apply changes
to both units (communicator and remote). Manufacture recommends changing wireless channels
to be done by technician.
Changing the system operation channel will allow more than one radio to operate in the same area
without interference. In addition, this will help to avoid interference between Amron wireless
system and any other wireless device (like telephone).
The communicator master transceiver card receives divers & tender audio signal from U6B. The
master transceivers transfer the audio signal to RF then transmits it through the antenna. At the
same the master transceiver receives at different frequency the RF signal from the remote
wireless, then it feeds remote wireless audio signal to the mixer U6C. The remote wireless
receives from and transmits to the communicator master wireless transceiver .
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