Control Unit, C-149/ARN-6 Radio Compass System

This is a terrific example of a C-149 Control unit for the aircraft receiver R-101 of the Radio Compass AN/ARN-6 system for direction finding and homing. The receiver function tunes from 100-1750 kHz across 4 bands, which were selected by rotating the center knob below the frequency band window.  The center knob rotates a flexible shaft connected to a rotatable loop antenna.

The AN/ARN-6 system evolved over time, originally using a control box similar to the BC-434A, and then in 1950's versions, using a smaller module (C-1514/A) without the signal strength meter integrated into the cockpit communication console with a much smaller loop antenna (AS-313) without a radome.  These were made by Bendix and Magnavox, but this unit does not carry the manufacturer's name on its data label.

The AN/ARN-6 system of post WWII-vintage (see diagram) typically consisted of the following components:

• Radio Compass Unit R-101/ARN-6
• Mounting MT-274/ARN-6
• Indicator ID-91/ARN-6
• Indicator ID-92/ARN-6
• Coupling Unit CU-65/ARN-6 (2)
• Control Box C-149/ARN-6
• Loop Antenna AS-.141/ARN-6

The unit is in exceptional cosmetic condition and all mechanical features appear to operate. Measures 5 inches by 8 inches by 4 inches deep (including knobs).