Ferra is a portable transceiver operating in the MF band. 

Below you may read the details.

Operating Frequency
0,8-5 MHz (custom available frequency)     
0,9-1,1 MHz (underground band)
1,8-2,0 MHz (surface band)

Output power: 1; 5 watt
Modulation: LSB (standart), USB (custom)
Radio size: 183х126х49 mm
Antenna size: 30х30х500 mm
Battery: 4,5 Ah, 11.1 V, Litium-ION
RX Sensitivity: 0,5 mKV

: internal modem for sending of a short text messages (especially reliable mode), full-size kayboard, storing of 10 last received messages.

There is no doubt there are many others different wireless transceivers. But we have only one question – will it work?

And Ferra works!

1. Terrestrial radio communication 
Ferra has been trialed repeatedly under various conditions. Our tests were in Omsk region, in Yakutia (Sakha) and in EU countries. The communication range varies depending of the features of relief, water barriers and forests.
The general test results are below:
Voice communication Ferra-Ferra is about 30-60 km. The Ferra sets are in hands of operators. Then raising the antenna increases communication range.
When to send short text messages increases communication range up to 100 km. This is important for areas where there is no cellular communication.

2. Underground radio communication
It is well known that the underground radio communication very difficult to ensure. Radio waves strongly absorbed by the rock strata therefore, the communication range is reduced. Especially if the radio waves pass through the rock strata directly, and not along the shafts or the wall of the caves.
Ferra was trialed in a number of mines and pits as well as in some natural caves to identify opportunities in such difficult conditions. Our radio transceiver was tested on Urals, in Rostov region and in Kazakhstan.

The general test results:
The communication range along the shaft is about 1,5-3 km (points of communication can be located in one mountain drift and in different, in parallel or perpendicular).
The communication range through the rock strata is about 1 km in message mode and less in voice mode.
We are sure that for Ferra radio with a weight of 2 kg shown results are interesting and deserve attention.
We didn’t find analogues, so we made Ferra.
If you've found similar, please contact us.

The set consist of a low-power and low-frequency transmitter (5 w) and ultra small antenna that is fixed on the shoulder of the miner.

Key Features
System «Ferra» provides communication range over a kilometer through the rock strata.

The system does not require any different guides (cables, railes).

The system «Ferra» is intended for radio communication in mines, diggings and caves.

General Specifications
Our results were confirmed by tests in the anthracite mines with significant inclusion of higly wet rocks.


Test protocol