2820A-XX & 2825A-XX SERIES TWO DIVER COMMUNICATOR USER MANUAL
282XA-UM
REV 5.0
19
Turn unit on and adjust volume controls as follows:
4.6.2
Tender should don headset and talk to himself. If adjustments are required,
increase or decrease Tender volume (controls). This will establish a system volume
level.
4.6.3
Tender (Volume Controls)
•
Earphone – Divers talk, while tender adjusts to a comfortable listening level.
•
Microphone – Tender talks and divers determine a comfortable listening level,
having the tender adjust as needed.
4.7
HELIUM SPEECH UNSCRAMBLER OPTION
4.7.1
HELIUM SPEECH UNSCRAMBLER (DSP3)
The Helium Unscrambler option is installed into the option panel located on right
side of the communicator. A Communicator with this option accommodates a wide
range of operating depths. This state-of-the-art digital design can accommodate a
multitude of functions ranging from the correction of the diver’s raw helium speech
to normal intelligible voice levels, advance treble boost and complex noise
reduction filters (NRF)
Diver radios configured with this option are only supplied with the AC power option.
This is due to the power requirements of the Unscrambler option. The radio can be
operated in the air mode by turning the HSU off.
Amron’s advanced NOISE REDUCTION FILTER (NRF) incorporates a complex
DSP algorithm which filters out background noise while allowing the diver’s speech
to be clear and intelligible. Amron NRF automatically captures the frequency
spectrum of applied background noise within the audio frequency bandwidth and
reduces it without affecting the diver’s speech.
The Treble Boost Control provides a means of adjustment to enhance the diver’s
microphone performance. The treble boost feature allows for optimum frequency
enhancement and improved intelligible speech from the diver’s voice.
The Depth Control is used to change the amount of shift in the frequency of the
diver’s voice. The depth control is advanced as the diver’s depth increases. There
is a certain amount of interaction between the controls, and also a difference
between diver voices, therefore it is necessary to tune the unit to the diver.
Intelligibility is the desired result; each operator will find a combination which works
best. The frequency shifting algorithm changes the amount of correction to the raw
helium speech. The Depth Control is a multi-turn control with a locking feature. This
allows the tender to finely adjust the level necessary and lock the control to prevent
accidental adjustments.
At power-up, all the controls should be in the minimum (far left) position. Have the
diver speak and adjust the DEPTH CONTROL as necessary to achieve the best
speech quality. Then adjust the TREBLE BOOST as necessary to improve the
quality. There is some interaction between these controls so you may have to go
Summary of Contents for 2820A
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