SR-FRS-4W (VHF:136MHz-174MHz and UHF: 400MHz-470MHz) is a low cost but high-performance integrated walkie talkie module. With built-in high performance micro controller, narrow band Rf transceiver and standard Uart interface, it can be easily used and succeed in all the walkie talkie function with good quality voice and long-distance transmission. Users only need to connect external audio amplifiers, microphone or speaker with this module, then it can work as a small walkie talkie. Simplified interface and ultra-small size make this module into a wide range of applications, also can conveniently embed into various handheld devices to improve the comprehensive performance of end products.
Besides the excellent voice intercom, the more important feature is this module has the data/SMS transfer ability; up to 80 bytes can be sent at one time; it is compliance with the standard UART transfer protocol.
Features:
FM demodulation technique Based on digital signal processing technology.
Frequency Range are VHF:136MHz-174MHz and UHF: 400MHz-470MHz:
Frequency step：5K/6.25K/12.5K/25K.
RF Output Power： 4W/1W
voice encryption (scrambling): 8 types.
Voice Compression- Expansion.
SMS Receive /Transformer，The wireless Baut: 1200.
CTCSS（38 group）+ CDCSS（83 group）.
Automatic elimination tail.
Volume adjustable（1-9）.
Vox level adjustable（0-8）.
SQ level adjustable（0-9）.
MIC sensitivity level adjustable（1-8）
The ultra-low power dissipation in Sleep Mode（0.1uA）.
Power supply ：DC 3.3～5.0V
Size：60 X 90 MM
Communication distance more than 7KM at open area
Applications：
portable intercom and paging systems.
wireless data transmission.
mobile phones and other embedded in radio functions product.
Portable walkie-talkie,
Outdoor sports equipment,
Building security,
Audio monitor system
Module connector
Module pin function define
|
NAME
|
NO.
|
comment
|
|
MIC_IN
|
1
|
MIC input
|
|
NC
|
2
|
NC
|
|
VCC
|
3
|
DC powe : 3.3-5V, recommend: 4V.
|
|
GND
|
4
|
GND
|
|
PTT
|
5
|
1: receive; 0: transmite
|
|
TXD
|
6
|
TXD for UART
|
|
RXD
|
7
|
RXD for UART
|
|
SQ
|
8
|
Squelch control
0: active
1: inactive
|
|
NC
|
9
|
NC
|
|
PDN
|
10
|
Module power enable，
0=SLEEP ；
1= Working;
It must be set high level when working;
|
|
AF_OUT
|
11
|
Audio output
|
|
P00
|
12
|
Program port
|
|
GND
|
13
|
GND
|
|
H/L
|
14
|
RF Power select:
NC: 4W
0: 1W
It do not be connected to a high level.
|
|
P01
|
15
|
Program port
|
|
GND
|
16
|
GND
|
Typical application Block diagram
