Though TM-990 series mobile twoway radios share an identical overall appearance, they differ significantly in version positioning, hardware details, and functional configurations, catering to diverse communication needs.

1. Version Positioning

TM-990: A basic POC-only radio, available in two sub-versions—standard and Bluetooth-enabled.

TM-990D: A dual-mode radio supporting both PoC and analog communication.

TM-990DD: The dual-mode model covering PoC and DMR digital communication.

2.Appearance Details

Handmic: TM-990 comes with a basic handmic. In contrast, both TM-990D and TM-990DD are equipped with full-keyboard handmics.

Rear Communication Interfaces: TM-990 only has core LTE and GPS interfaces. TM-990D adds an analog interface. TM-990DD adds a DMR interface.

3. Functions

Bluetooth Function: Only TM-990 offers a Bluetooth option, enabling wireless connection with Bluetooth accessories for enhanced mobility. This feature is absent in TM-990D and TM-990DD.

Repeater Function: TM-990 lacks this function and only supports point-to-point direct communication. Both TM-990D and TM-990DD have a repeater function, acting as small communication hubs to improve coverage and stability in complex environments.