Use of Automatic Recording Equipment in Radio Transmission Research

This is an apparatus paper describing equipment recently developed for low frequency (17.8 kc); intermediate frequency (770 kc); and high frequency (6942.5 kc) field intensity recording. The circuits employed are presented and discussed with particular reference to expedients for obtaining nearly logarithmic scales (when used with Leeds and Northrup recording potentiometers). Typical records obtained with the aid of the equipment described are presented and the salient characteristics of the high-frequtency records (which show striking evidence of skip distance phenomena) are pointed out.