Power grid overhead transmission lines pass mainly through uninhabited areas where wireless telecommunications signal is mostly low-level. This is the main obstacle to their optimal maintenance and monitoring so aim of the document is to analyze construction of a WLAN wireless network via base stations along a path of the transmission line. Due to simple legislation procedure and low price an unlicensed ISM radio band with emphasis on 2.4 GHz spectrum was chosen. Achieved range between base stations are higher than the average distance between two bevel points on the transmission line so the number of base stations could be approximately minimized. Interference in inhabited areas is reduced by using dynamic channel allocation, directional antennas, more favorable polarization of electromagnetic waves and by using the IEEE 802.11g standard which is the most resistant to multipath reflections. By networking all of devices for controlling, signaling, measurement and surveillance, providing voice communications and access to other information systems potentially anywhere in the path, it is possible to build an optimal 'Technical-Information System’ for transmission lines. Such a system offers a quick return to the normal state of maximum possible number of customers during unplanned outages, measurement the number of parameters of the power grid in arbitrary places, efficient maintenance due to available voice communications, mobile access to a databases and surveillance over parts of the power grid. The WLAN network is sufficient secured from outside intrusion, but it could be very easily interfered so as not to be used for systems where the availability is the main criteria for design of telecommunication networks.