72 FAA Chart Users’ Guide - IFR Enroute Symbology RADIO AIDS TO NAVIGATION (Continued) Frequency Protection Frequency Protection usable range at 18,000’ AGL - 40 NM Frequency Protection usable range at 12,000’ AGL - 25 NM DISTANCE MEASURING EQUIPMENT Facilities that operate in the “Y” mode for DME reception VOICE COMMUNICATIONS VIA NAVAID Voice Transmitted No Voice Transmitted NAVAID SHUTDOWN STATUS PART TIME OR ON-REQUEST (L) (T) (Y) VHF/UHF LF/MF VHF/UHF LF/MF Navigation and Communication Boxes - Common Elements AUTOMATED WEATHER BROADCAST SERVICES ASOS/AWOS - Automated Surface Observing Station/Automated  Weather Observing Station LATITUDE AND LONGITUDE Latitude and Longitude coordinates are provided for those NAVAIDs that make up part of a route/airway or a holding pattern.  All TACAN facilities will include geographic coordinates. VHF/UHF LF/MF LOW ENROUTE HIGH ENROUTE Navigation and Communication Boxes - Examples LOW ENROUTE CHARTS VOR R - Receive only 122.1R Controlling FSS Name - ANDERSON (T) - Service Volume  Receive & Transmit on 122.35 (T) - Service Volume  Latitude and Longitude Controlling FSS Name - MACON HIGH ENROUTE CHARTS VOR