
MM-014716-001 
3 
TABLE OF CONTENTS  Page 
1 SAFETY SYMBOL CONVENTION....................................................................................................9 
2 RF ENERGY EXPOSURE INFORMATION ...................................................................................10 
2.1 RF ENERGY EXPOSURE AWARENESS, CONTROL INFORMATION, AND OPERATION 
INSTRUCTIONS FOR FCC OCCUPATIONAL USE REQUIREMENTS.............................. 10 
2.1.1 Federal Communications Commission Regulations......................................................10 
2.2 COMPLIANCE WITH RF EXPOSURE STANDARDS........................................................... 11 
2.2.1 Mobile Antennas............................................................................................................11 
2.2.2 Approved Accessories................................................................................................... 12 
2.2.3 Contact Information.......................................................................................................12 
3 OPERATION SAFETY RECOMMENDATIONS............................................................................13 
3.1 TRANSMITTER HAZARDS..................................................................................................... 13 
3.2 SAFE DRIVING RECOMMENDATIONS................................................................................13 
4 OPERATING RULES AND REGULATIONS..................................................................................14 
4.1 OPERATING TIPS.....................................................................................................................14 
5 PRODUCT DESCRIPTION................................................................................................................15 
5.1 CH721 CONTROL HEADS....................................................................................................... 15 
5.2 INTERCOM OPERATION........................................................................................................ 16 
5.3 GPS RECEIVER.........................................................................................................................16 
6 CHANGE OPERATING MODE........................................................................................................ 17 
6.1 CHANGE FROM OTP MODE...................................................................................................17 
6.2 CHANGE TO OTP MODE.........................................................................................................17 
7 OPENSKY OPERATION....................................................................................................................18 
7.1 CH721 FRONT PANEL COMPONENTS................................................................................. 18 
7.2 POWER UP AND VOLUME CONTROL................................................................................. 20 
7.2.1 Power Up....................................................................................................................... 20 
7.2.2 Volume Control............................................................................................................. 20 
7.3 SELF-TEST.................................................................................................................................20 
7.4 LOGIN TO THE NETWORK.................................................................................................... 20 
7.5 LOG OFF THE NETWORK.......................................................................................................21 
7.6 TURNING THE RADIO OFF.................................................................................................... 21 
7.7 MENU DISPLAY AND CONTROL AREA..............................................................................21 
7.8 RADIO STATUS ICONS........................................................................................................... 22 
7.9 DWELL DISPLAY.....................................................................................................................22 
7.10 PERSONALITY .........................................................................................................................22 
7.10.1 Profiles...........................................................................................................................23 
7.10.2 Talk Groups................................................................................................................... 23 
7.11 ALERT TONES.......................................................................................................................... 24 
7.12 BASIC MENU STRUCTURE.................................................................................................... 24 
7.13 DUAL-TONE MULTI-FREQUENCY.......................................................................................27 
7.14 KEYPAD COMMANDS (SYSTEM MODEL CONTROL HEAD)..........................................27 
7.14.1 Password Entry.............................................................................................................. 27 
7.14.2 DTMF Overdial............................................................................................................. 27 
7.15 CHANGING THE ACTIVE PROFILE......................................................................................28