On a Determination of the Energy Losses in a Radio Telegraph Transmitter

A simple method of calorimetry is devised to measure the total losses of a modified Chaffee gap 0.25 K.W. transmitter. The equilibrium temperature of the air in a slightly heat-conductive box containing the transmitter under test enables the direct determination of the heat evolved. A supplementary calibration with known heat evolution renders the method simple and free from certain previously common calorimetric complications. The thermometer used must be shielded from direct radiation from the transmitter. Guided by results thus obtained, the authors increased the over-all efficiency of the set under test from 48 to 70 per cent.