Bernard ZL2BD talks on small magnetic loop antennas
Bernard presented on small magnetic loop antennas at the June meeting. Bernard has been working on these for many years, and the main message was -They work very well but must be made very carefully and you need to accept a number of limitations.
The main limitation is the very small bandwidth, followed by the high level of care required in designing and making them. A key issue is loop resistance. Bernard makes his loops from 1 inch copper pipe and to reduce the resistance from the joins, uses 4 x 90 deg angles, carefully silver soldered. His loop is a square!