The main criteria that the customer specified were:-
1, The unit had to enclose 2 x high capacity batteries that could be removed simply for transportation and shipping.
2, The unit had to contain a battery condition indicator,
3, The unit had to be capable of being used in extreme temperatures, (eg. Middle East/Africa)
4, The unit had to report if the radio was operating on the unit’s internal batteries,
5, The unit was required to have the smallest possible footprint.
6, The unit had to be very quiet, as it was to be used in office and domestic environments
Before approaching Consam, the customer had used an off the shelf solution unsuccessfully. They then decided to have a bespoke unit designed and built from scratch to suit their particular needs. Consam designed a compact housing that contained the Hytera MD785 UHF radio unit, along with the 2 specified high capacity rechargeable batteries, and the required switch mode power supply.
Several prototypes were built from scratch until the customer was satisfied. These prototypes included a variety of fans and battery conditioning indicators. Consam ran the radio unit on the internal batteries to ensure the correct operation of the battery indicators, and the unit was run in an increasingly hot environments to ensure that the thermostatically controlled fans operated as expected.
The prototypes were also used to perfect the battery tray insertion and extraction mechanism ensuring that the installation and replacement of the batteries was as user friendly as possible for the customer. After the prototypes were all tested it was considered that the fan was too noisy for use in an office / domestic environment, and the initial battery indicator was constantly on, resulting in a bright LED light being visible at all times.
These problems were resolved by carefully testing a variety of components to ensure that the fan only came on in extreme heat conditions and would not be heard by the user.
The LED issue was cured by developing a “reverse” circuit where by the LED light only illuminated under fault conditions or when the unit was running on the internal batteries.
This meant that the unit could not only be used in traditional offices but could also be used in sleeping quarters, meaning that the unit had to be quiet, discrete, and yet capable of operation during power cut/outage.
The Consam produced unit means that the F.C.O. Hytera radio system will continue to operate during a power cut, very high ambient temperatures and yet be quiet enough and discrete enough to be situated on a bedside table.
