SBDA Amplifier

As with any communication system, the SIAMnet RF signal diminishes in strength as the cable length increase. The longer the cable the weaker the RF signal gets.

SIAMtec has designed  a compact bi-directional amplifier (called SBDA) to compensate for propagation losses in the cable as well as coupling losses at the antennas sites. This SBDA amplifier is specifically designed to interface with the 75 ohms CATV cable technology.

The amplifier is powered from the coaxial cable.  A conventional CATV power supply feeds AC power into the coaxial cable from either the Head-end or from any other location downstream (into the mine).

The amplifier gain is manually set during the installation phase to adapt to the actual network configuration.
SBDA block diagram

The amplifier has been designed with redundancy in mind by using dual transistors per amplifier stage.

If one transistor should fail, the overall amplifier output would drop by only 6 dB allowing communication services to remain operational
SBDA Housing

The SBDA housing protects the electronic components from water and dust and dissipate internally generated heat.

The housing is supported by a messenger cable.  Two gaskets protect the circuit against water and provide RF shielding.  Four port plugs in the cover enable access to test points.