| Feature | R3.x Behavior | R4.0 Behavior (Manual Notes) | | :--- | :--- | :--- | | | Up to 90 seconds | Improved to < 60 seconds | | SDS Length | 140 characters | 256 characters | | Talk Group Queue | No visual indicator | On-screen scrollable queue | | Bluetooth Support | Not available | Basic (wired headset only – R4.0 adds stable pairing) | | Over-the-Air Programming (OTAP) | Partial support | Full config file push from dispatcher |
This feature allows a dispatcher to activate the microphone of an MT680 remotely to listen to the environment inside the vehicle. The manual stresses legal compliance before use. Hytera Mt680 Tetra Mobile Terminal Owners Manual R4 0
The R4.0 firmware brings advanced capabilities that require configuration via the . | Feature | R3
: Guidance on using the 4W internal speaker and noise-canceling technology to ensure clear communication in high-noise environments. : Guidance on using the 4W internal speaker