This unit was developed based on the cooperation with sveral technical experts in our field as well as with the forces in the field. We have maximized the sound quality of the unit by using Knowles microphones and 3G network. The 3G listening unit features 2 microphones, one is located on the unit circuit board directly for voice detection and other which is used as an external microphone.
Combination of two microphones resuls in very long battery life, accompanied by excelent quality sound. There are several safety mechanisms, which we have implemented in order to ensure secure yet smart communication.
Key features:
- Digital preamplifier paired with AGC (automatic gain control) function of the module for better and clearer sound
- Real-time gain control via DTMF tones
- Sleep time/ Dead time for extremely long battery life
- Possibility to select band 2G/3G
- Smart VOX hanging up protocole
- Password protected listening (optional)
- Master number setting
Commands of 3G listening unit
Sleep mode
This mode is usually activated when you need for the device to discretely inactive. What it does essentially is that it will turn itself off, shot down connection to the network and then wake up. If there are command waiting, such as to wake up, it will power on. In case there are no commands waiting it will again shut itself off.
Real-time audio management
By using the DTMF tones, you have several options to set the microphone settings to the optimal mode. The unit is programmed to pick up sound from far distance. Therefore testing it by speaking to the microphone from 1 meter does not make much difference. What does make a difference is the distance in which the microphone can pick up the sound. The sound quality is paired together with the singal reception, therefore if you will not be having a strong signal the sound quality will to be impaired.
Watchdog function
No matter what you do with electronics, there comes a time when somehow the unit jams. For this, we have implemeted a function which eliminates this jamming. When the fault is detected the device will restart itself and after booting it will work again.
NOTE: Device can be made with EXTERNAL or INTERNAL microphone. The battery can be either mounted onto the device or it will be supplied with desired battery, the standard is 3600mAh in the packaging.
