The ARA-25 is a VHF/UHF direction finder designed and manufactured by  in the 50s and 60s for airborne use. This unit operated in conjuntion with ARC-27s, ARC-55s and ARC-51s to provide Air to Air or Air to ground ADF functionality.
The ARA-25 consists of a servo amp (left below), a junction box (center below)  and a rotating antenna (right below).

The unit below was purchased for about $25.  The antenna presented some water damage but was reparable.