Figure 1-2. Radio Receiver R-1391 / ARN-83.

AIR VENTS

HANDLE

ANTENNA

CONNECTORS

HOOK

TM5826-225-12-2

Figure 1-2. Radio Receiver R-1391 / ARN-83.

trical connector and at the other end by a locknut

1-10. Description of Receiver Mount

(fig. 1-3)

that engages a hook at the front of the receiver.

Two ground straps connect the two aluminum

The receiver mount serves as a shock isolator,

frames together for electrical ground continuity.

mating electrical connector support, electrical

power and signal distribution center, mount for a

1-11. Description of Control Unit

dc-to-ac inverter, and the means of securing the

receiver to the aircraft. The inverter accepts +27.5

volts dc and supplies 26 volts alternating current

a. The control unit remotely controls the receiver

and contains the necessary controls for selecting the

(ac) at 400 cycles per second (cps) for synchro

frequency range, tuning the receiver, and selecting

excitation. Mechanically, the receiver mount com-

all direction finder set operating modes. A tuning

prises two aluminum frames separated by five

meter indicates signal strength.

vibration isolators. One frame (base) is secured to

the aircraft with eight screws. The upper frame

b. The control unit is inclosed in a removable

dust cover and mounts on either the pilot's instru-

supports the receiver at one by the mating elec-