AN/ARM-186 Rockwell Collins Test Set Receiver

The Rockwell Collins / Evans & Sutherland AN/ARM-186 Test Set Receiver is a compact, portable, battery-operated uhf/vhf signal generator. Test set transmissions, which simulate VOR, GS, LOC, and MB ground station signals, are used to examine the response of aircraft navigational systems. The logic and control circuitry in circuit card assembly A6 directs and applies operating voltage to rf modules selected by the control panel switch settings. This circuitry also generates modulation signals used by rf modules to develop appropriate rf frequencies. The rf modules receive operating voltage and modulating signals from their respective portions of the circuit card assembly. Fixed or variable modulating signals are applied to the LOC, GS, or VOR modules. Fixed modulation only is applied to the MB module. The rf modules then provide carriers for the modulating signals. The modulated rf output signals from the LOC, GS, and VOR modules are applied to the GS/VOR/LOC antenna through an attenuation and combining network. The attenuators can be adjusted by controls on the front panel to provide 0 to 110 db of attenuation. The MB rf output signal is fed through an impedance matching network to the separate MKR BCN antenna.