SR105U (UHF:400M-480MHZ)  is an ultra-compact and high-cost performance wireless voice intercom and long-distance data transmission module. It has a high-performance radio frequency transceiver chip, microcontroller and radio frequency power amplifier. The external controller can set the module operating parameters and control the entire module transceiver through standard UART (TTL level) communication. The module only needs an external antenna, MIC and audio amplifier to form a complete intercom or digital transceiver. After setting the module parameters, it can be powered off and saved. In simple applications, an external single-chip microcomputer is not required.

Features:

•Based on digital signal processing technology modulation and demodulation technology;

•Frequency range: 400MHZ~480MHZ;

•Frequency stepping optional: 5K/6.25K/12.5K/25K; 

•RF output power: 0.5W 

•Voice encryption (frequency modulation) function: (7 options)   

•Short message SMS send and receive (remote control, data transmission) function;  

•Signal strength RSSI query 

•DTMF transmission, demodulation function (if needed, please contact customization)

•Built-in CTCSS (38 groups), CDCSS (83 groups) encoding and decoding, support normal and reverse phase; 

•Automatic squelch function;  

•Digital volume control: (1-9 levels) adjustable; 

•Voice-activated hands-free call trigger sensitivity: (0-8 levels) adjustable; 

•Static noise level: (0-8 levels) adjustable; 

•MIC sensitivity adjustment: (1-8 levels) 

•Transmit timing TOT, 1-9 minutes can be set 

•High receiving sensitivity: -121dBm;

•Ultra low power consumption (sleep mode): (0.1uA);

•Voltage operating range: 3.3V~5.0V, recommended operating voltage 3.7V-4.2V, the power supply must provide more than 0.5A current  

•Ultra small size: 15*25*3.0mm;

•Reference communication distance: open area 2-3 km;  

The actual communication distance depends on (transmit power, receive sensitivity, antenna length, placement/matching, usage environment, etc.).

Application:

1. Portable intercom and paging system; 

2. Long distance wireless remote control, data transmission system; 

3. Mobile phones and other products embedded intercom functions brand new design 

Please note that:

SR105U pins/instructions are compatible with FRS-0W5U, and the functionality has been enhanced. 

There is a slight difference in the instruction response time.

In the group setting command, the setting positions of the receiving frequency and transmission frequency have changed.

Module pin assignment

Typical application Block diagram   

Useful Link:

AT Command for UHF/VHF Walkie Talkie radio module