ABSTRACT
In the fall of 1935 GEMA installed the second radar of a series of three sets, on which von Willisen tried out an improved lobe-switching modification. Instead of using a separate receiver for each antenna, the two antennas were connected by a switch driven by a synchronous motor to a single receiver, the outputs being switched in synchronization to the vertical deflection plates of two CRTs in the indicator. The two screens were observed and compared stereoscopically simultaneously. A single receiver did not lead to an improvement in the bearing accuracy, but operation was simplified, because only one receiver had to be controlled, and any creeping variation of frequency and gain affected both signals equally and did not affect comparison on the screens.
