Axnes Aviation AS
Document number
Revision
Date
AX-PSB-UMAN-0027
Issue E
2015-03-05
Page 1-4
The control functions are as follows:
Display for channel indication, and configuration menu (located on top).
Channel selector (located on front).
Volume and power on/off (located on the left hand side).
Large PTT button for helmet/headset operation (located on front)
PTT button for walkie talkie operation (located on left-hand side)
Loudspeaker for walkie talkie operation (located on front)
Microphone for walkie talkie and casualty communication (located on front)
1.4 Electrical and functional description
The MP20 is the handheld unit in a wireless extended ICS system and interacts with the
Polycon 004RLI base station. A MP20 is typically connected to a winchman helmet/headset,
and implements the following features:
Wireless extension of aircraft
’s intercom system with significant range and
robustness.
Range up to 10 nm line of sight over water, and good ability to penetrate into
structures.
Operating in half-duplex mode and utilizes the UHF band.
Support for selected Maritime VHF channels (MP20 dual band only)
Programmable with up to 16 channels.
NIVOX
– Polycon patented VOX operation. Conventional Voice Operated
transmission (VOX) operates by opening transmission when input has reached a
certain l
evel over a given period of time. This will normally cause ‘clipping’ of the first
word in the transmission, and may cause difficulty in differentiating between words
such as ‘No’ and ‘Go’. Polycon implements a Non Interrupted Voice Activated
transmission (NIVOX). Polycon NIVOX will ensure non-clipped transmission of all
input, and full words are transmitted, without the drawback of traditional VOX.
Adaptive NIVOX trigger level. The NIVOX will monitor the ambient noise, and through
this process avoid triggering transmission based on high background noise levels. A
given voice overlay to the noise is needed to trigger transmission. This functionality
secures that the intercom is not flooded with the background noise.
Easily available PTT button (designed for elbow operation)
Protected channel select buttons.
Protected Volume/power on/off buttons
“Low profile” antenna
Built-in loudspeaker and microphone for MP20 operation (Walkie-Talkie).
Intercom from integral microphone to helmet/headset earphones for casualty
communication.
Side mounted PTT key for MP20 operation (Walkie-Talkie)
Side-Tone function.
Rugged and salt water resistant aluminium enclosure.
Waterproof to 1 meter
