During the first few weeks of 1945, the commanding officer of 23rd Antiaircraft Artillery Group, Colonel J.B. Fraser, wrote a substantial report called Detecting Ground Targets by Radar. The text that follows replicates the entirety of this report. The only changes made either fill out abbreviations, update punctuation, or split large paragraphs into smaller ones. Brief explanations hide within brackets.
Basis for Report
To obtain further data on the use of radar to locate ground targets (see Immediate Report No. 90, Headquarters Twelfth Army Group), two SCR-584 sets of the 68th Antiaircraft Artillery Gun Battalion, with the battalion radar officer and radar crews, were attached to the 23rd Antiaircraft Artillery Group to work with XV Corps artillery. Findings in this report are based on intensive use of these sets since 30 December 1944. At present this work is being carried on by Major John W. Green, radar officer of the 23rd Antiaircraft Artillery Group, and Lieutenant John W. Post.
Installation and Siting
Map reconnaissance was made for suitable sites. Relief maps, 1:50,000 scale, were used where available. Terrain models, it is believed, would be better. Final reconnaissance must be on the ground. A few yards may mean the difference between a good and bad location, and final selection must be determined by actual operation of the set. There must be a line of sight from the radar to the target area.
Types of Sites
Dug-in emplacement (on top or on the forward slope of a bare hill). Because it must be well forward, such an emplacement must be dug at night. Digging in is a considerable job. There is much spoil. It takes time to emplace the set and time to remove it from such an emplacement. Chief advantage is protection from shell fire.
In a quiet sector the SCR-584 has been run forward at night and set up on a little-used road or other hard surface. Advantages include a quick move if necessary and a quick means of testing the effectiveness of sites. Disadvantages include the necessity of a ready means of orientation, no protection from shelling, and some loss of time in moving up and back.
The set may be concealed in an existing house or fortification in daytime and run out for night operation. If the fortification happens to be just the height of the carrying van, the set could be left behind the fortification and the antenna elevated during darkness and lowered before day.