EMI/RFI Survey at Detachment K

摘要

During this survey several new and major sources of radio interference were encountered. While the brief visit did not allow time for the identification of all sources of interference, several were identified. Major sources were the insufficient dynamic range of the site's multicouplers and their inability to cope with the normal ambient signal environment as well as intermodulation components generated from the operation of an onsite ionospheric sounder at full power. Time was not available to identify the source of an erratic and high-level intermittent interference across the entire HF, VHF and UHF bands. Other items noted are the many nonlinear joint in the antenna towers caused by welding on galvanized steel, incidental contacts between wires and metal objects, and an unnecessary power-conversion device to control the speed of a cabinet fan.