Direction Finding DF Indicator of R.1155 Nav-Com System C-118 This is a WWII-era M1

This is a WWII-era M1 Gunner’s Quadrant

which used pressure sensors at the engines which electrically transmitted the signal to these electrical indicators

This is an original set of Handbook of Operation and Service Instructions AN 05-15-16 May 1944 and Revisions August 1944 for the Gyro Stabilized Flux Gate Compass System

there is a locking screw that captures the rotating ring and preventing unintended rotation

Direction Finding DF Indicator of R.1155 Nav-Com System C-118 This is a WWII-era M1Here is a WWII era Direction Finding (DF) Indicator as used in aircraft of the British Royal Air Force, such as bombers Avro Lancaster, Handley Page Halifax, and Vickers Wellington, and patrol bomber Short Sunderland. The DF Indicator received its signal from the R. 1155 receiver in the radio (wireless) compartment. By seeking a signal from a ground transmitter, the indicator displayed the direction of the transmitter in relation to the aircraft by