DMR818S Walkie Talkie Module -- A Long-Distance Intercom Solution Compatible with Digital and Analog Systems

The DMR818S is a 2W long-distance digital walkie-talkie module from NiceRF, featuring a built-in microcontroller, digital intercom chip, and RF power amplifier circuit. This module is compatible with common analog walkie-talkies on the market and also includes digital walkie-talkie functionality. It provides customers with a standardized serial interface, allowing for quick and easy setup of the module's transmit and receive frequencies and contact parameters via serial commands. The high integration of the module enables users to connect external audio amplifiers, microphones, speakers, and other components, allowing it to function as a compact digital walkie-talkie.

In DMR mode, digital walkie-talkies support the following functions:

In DMR mode, digital walkie-talkie modules support multiple functions, including sending SMS communication, voice and SMS encryption, all-call, group call, and individual call functions. Additionally, the module provides call alert, supports caller and callee detection, has a built-in emergency alarm function, and supports voice and SMS applications in both direct and repeater modes.

Analog walkie-talkies support the following functions:

Analog walkie-talkie functions include CTCSS/CDCSS sub-audio settings and adjustable squelch levels. The CTCSS/CDCSS sub-audio settings can effectively reduce interference and improve communication quality. The squelch level adjustment ranges from 1 to 8 levels, with each level differing by 2dBm. The adjustable squelch levels allow users to set the appropriate squelch level according to actual needs, ensuring clear communication.

FCC、CE certification

The DMR818S is produced and tested strictly using lead-free processes, meeting RoHS and Reach standards. The DMR818S module also offers versions that can obtain both FCC and CE dual certification to meet different market needs.

long-distance communication

The DMR818S is configured with a 2W transmission power, allowing for a maximum transmission distance of up to 5 kilometers. Even in environments with multiple obstacles, it maintains signal clarity and coherence.

high integration and compact size

The DMR818 features high integration and a compact size, with a built-in microcontroller, digital walkie-talkie chip, and RF power amplifier circuit. Its small-size design and quick setup via serial commands provide users with an easy-to-integrate and deploy solution, making it especially suitable for applications in confined spaces.

TCXO crystal oscillator

The walkie-talkie module uses a 1ppm TCXO crystal oscillator, ensuring the module maintains precise frequency in various environments, thereby providing stable and reliable communication performance. This high-precision oscillator reduces frequency drift, enhancing the overall communication quality and reliability of the walkie-talkie.

In addition to the above-mentioned features and product highlights, the DMR818S also has the following characteristics:

Dual Time Slots: The walkie-talkie module features dual time slots functionality, which means it can support two independent communication channels on the same frequency.  dual time slots technology effectively increases spectrum utilization, allowing more users to communicate on the same frequency without interference. This enhances communication  efficiency and network capacity, making it particularly important for environments that require simultaneous handling of multiple communication channels, ensuring a stable and reliable communication experience.

Built-in EEPROM: The walkie-talkie module features built-in EEPROM, allowing for reliable storage and retrieval of configuration parameters and user data. Even after a power loss, it maintains data integrity and security, ensuring the walkie-talkie can quickly restore to its preset state under any circumstances.

Built-in AMBE++ Vocoder: The walkie-talkie module features a built-in AMBE++ vocoder, which efficiently compresses and decompresses voice signals, providing clear audio quality and higher voice transmission efficiency. AMBE++ technology delivers superior audio quality even in bandwidth-limited conditions, ensuring clear and natural voice communication in various environments, thereby enhancing the user's communication experience.

UHF band frequency: 400~470 MHz

VHF band frequency: 134~174 MHz

350 band frequency: 320~400 MHz

Distance up to 5Km

Max power output to 2W, low power to 0.5W

High Sensitivity: -124dBm

Bit error rate down to 1% under -121dBm

Independent frequency for Tx and Rx.

9 adjustable volume

Analog Bandwidth: 12.5 / 25 KHz   

Digital Bandwidth:6.25KHz

Message transmission and reception

DMR(Digital Mobile Radio)/ Analog walkie talkie

Built-in EEPROM, data saved even powered off

1ppm TCXO crystal

51 CTCSS

166 CDCSS