The Hytera HM685 is a professional, entry-level Digital Mobile Radio (DMR) mobile transceiver designed to provide clear, reliable communication in vehicular and desktop base station configurations [hytera.co.za]. Positioned as a cost-effective yet highly feature-rich solution, the HM685 bridges the gap between basic, entry-tier hardware and advanced trunking networks, making it a preferred choice for logistics, transportation, utilities, and corporate security fleets.
| KEY OPERATIONAL FEATURES | |
| AI-Based Noise Cancellation | Uses advanced artificial intelligence noise cancellation technology to reduce up to 30 dB of steady-state and intermittent background noise. Helps deliver clearer voice communications in vehicles and environments with high engine, road or operational noise. |
| Transflective Alphanumeric Display | Features a clear transflective alphanumeric display that uses ambient light to improve visibility in bright conditions, while supporting readability in low-light and nighttime vehicle environments. |
| Mixed Analogue & Digital Auto-Detect | Supports mixed-mode analogue and digital operation, automatically identifying compatible incoming signals and selecting the appropriate receiving mode. Enables organisations to transition gradually from analogue to digital radio communications. |
| TDMA Direct Mode Dual-Slot Capacity | Supports two-slot Time Division Multiple Access (TDMA) technology, enabling two independent communication paths within a single 12.5 kHz channel in supported direct-mode configurations. Increases communication capacity without requiring repeater infrastructure. |
| Wireless Connectivity & Programming | Supports an optional Bluetooth module for connection to compatible wireless audio headsets and remote Push-to-Talk (PTT) accessories. Also provides PC programming capabilities for convenient radio configuration and fleet management. |
| Enhanced Fleet Safety Systems | Includes emergency alarm functionality, Lone Worker monitoring timers and priority call interruption features to support driver safety and help ensure urgent communications receive priority during critical situations. |
| TECHNICAL SPECIFICATIONS | |
| Frequency Bands | VHF: 136–174 MHz UHF: 400–470 MHz |
| Digital Protocol | ETSI TS 102 361-1, -2 and -3 (DMR Tier II Conventional) |
| Channel Capacity | 512 channels across up to 16 programmable zones |
| RF Transmit Power | Low Power: 1–25 W High Power (VHF): 5–45 W High Power (UHF): 5–45 W |
| Channel Spacing | 12.5 kHz / 20 kHz / 25 kHz (switchable) |
| Environmental Protection | IP54 rated – dust-protected and resistant to water splashes. |
| Military Durability | Designed to meet applicable MIL-STD-810G environmental durability test requirements. |
| Audio Output Power | Internal Speaker: 3 W External Speaker Output: 8 W |
| GPS Module | Integrated GNSS positioning on the HM685(G) variant, supporting GPS, GLONASS and BeiDou (BDS). |
| Operating Voltage | 13.6 V DC ±15% (nominal) |
| Dimensions (W × H × D) | 164 × 43 × 130 mm (compact design) |
| Device Weight | Approximately 1.1 kg |
