The AN/AIC-2 Interphone System was introduced in 1943 to solve a number of problems with the old RC-36 systems in use in American aircraft. A perusal of the Unsatisfactory Report Digests for 1943 show an increasing number of complaints about the old RC-34, 35, 36, 51, and 175 interphone systems. Besides the continuing drumbeat of component failures (the single VT-99 (6F8G) tube was often highlighted as obsolete and failure-prone), there was the increasing relization that some sort of volume increase was needed as higher bombing altitudes were reached. As a result, along with band-aid fixes, there was an announcement that a new Interphone amplifier was being fielded to combat units in order to counter the problems. It included its own dynamotor, had a more powerful push-pull PA stage, and more flexibility of use. After the war, it was frequently modified for use in ham radio circles as a HI-FI amplifier.

C-97/AIC-2 altitude gain control, and AM-26/AIC on MT28/ARN-5 mount