Measurement of Loop-Antenna Receivers

The most practical method of introducing the measuring signal into loop receivers is to employ a transmitting loop connected to the signal generator. Several such loops are described, varying with regard to the use of shielding, frequency range covered, method of computing the field strength produced, and other particulars. The types described in the latter part of the paper are in use and giving satisfactory service at the present time. Precautions against stray fields and near-by metal objects are discussed briefly. Measurements on receiving loops, aside from general receiver tests, are described and formulas given. The results of such measurements on three groups of loops, totaling 30 in number, are reported. The paper closes with an Appendix giving the derivation of a few formulas of interest.