The AN/ARR-5 receiver was one of a number of commercial sets that were modified in 1942 to fit into a standard ARINC enclosure. Originally a cross between the big Hallicrafters S-27 and S-36 "UHF" radio receivers, the mods involved elimination of the high power "HiFi" audio amplifier and power supply, adding a separate power supply (also in an ARINC enclosure), motor driven scanning tuning with adjustable limits, and some tweaking of circuits internally to meet military internal oscillator radiation limits, among other things. Below are five manuals for the set that went through a bewildering evolution of changing document nomenclature formats up through the Korean War.
Handbook of Operating Instructions for Radio Receiving Set AN/ARR-5 (20 May 1953 update as T.O. 16-30ARR5-2 - later T.O. 12R4-2ARR5-1)