86-0755-61596687
312, Bldg. A, Hongdu Business Building, Zone 43, Baoan Dist., Shenzhen, Guangdong, China (Mainland)
D MR818 is a 2W long distance DMR walkie talkie module, it comes with built-in high performance microcontroller, digital mobile radio IC and RF power amplifier. All parameters(CTCSS, CDCSS, SQ, Predefined channels etc.) can be easily modified with protocol. With external power supply, speaker, and audio amplifier, it is easy to become a professional digital walkie talkie. Simplified interface and Ultra small size make this module widely used in various applications and conveniently embedded into various handheld device.
Remark:there are two versions of this module: DMR818-NVOC & DMR818-AMBE.
Ø DMR mode:
n Message transmission and reception.
n Message calling return receipt;
n Enhanced encryption of Voice and Text message.
n Various voice call types: All call, Group call and Private call;
n Reminder for input calling, calling status checking
n Emergency alarm and radio monitor;
n Radio kill and activate;
n Repeater
Ø Analog mode:
n CTCSS/CDCSS configurable
n Squelch levels configurable
n UHF band frequency: 400~470 MHz
VHF band frequency: 134~174 MHz
350 band frequency: 320~390 MHz
n Distance up to 5Km
n Max power output to 2W, low power to 0.5W
n High Sensitivity: -124dBm
n Bit error rate down to 1% under -121dBm
n Independent frequency for Tx and Rx.
n 9 adjustable volume
n Analog Bandwidth: 12.5 / 25 KHz
Digital Bandwidth:6.25KHz
n Message transmission and reception
n DMR(Digital Mobile Radio)/ Analog walkie talkie
n Built-in EEPROM, data saved even powered off
n 1ppm TCXO crystal
n 51 CTCSS
n 166 CDCSS
n DMR walkie talkie module
n Invisible intercom system
n building security system
n audio surveillance system
Parameters | Test condition | Min. | Typ. | Max | Unit | |||
Voltage range | 3.3 | 4.2 | 5.0 | V | ||||
Operating Temperature | -20 | 25 | 60 | ℃ | ||||
Frequency range | @UHF | 400 | 470 | MHz | ||||
@VHF | 134 |
| 174 | MHz | ||||
@350 | 320 |
| 390 | MHz | ||||
Start time |
|
| 100 |
| ms | |||
Uart baud rate |
|
| 57600 |
| bps | |||
Current consumption | ||||||||
Sleep current | < 1 |
| uA | |||||
Rx current | 50 |
| mA | |||||
Tx current (high power) | @VCC=4.0V | 800 |
| mA | ||||
Tx current (low power) | @VCC=4.0V | 400 |
| mA | ||||
RF parameters | ||||||||
Tx power(high power) | @VCC=4.0V |
| 1.5 |
| W | |||
Tx power(low power) |
| 500 |
| mW | ||||
adjacent-channel power | @12.5K offset |
| -62 |
| dBm | |||
Mic input voltage |
|
| 0.1 | 1.6 | Vpp | |||
Rx parameters | ||||||||
Sensitivity |
|
| -124 | dBm | ||||
Receiving BER(DMR modulation) |
@ -121dBm |
|
1 |
% | ||||
Audio output amplitude |
|
| 1.6 | 3.0 | V | |||
Audio Output impedance |
|
| 30 | KOhm | ||||
Pin NO. | Pin name | Description |
1 | MIC_IN | Microphone or line in |
2 | UART-TX | Transmit |
3 | UART-RX | receive |
4 | SWCLK | Reserved |
5 | SWDIO | Reserved |
6 | ARM_RST | Reserved |
7 | ANT | connect 50 ohm antenna |
8 | GND | Ground |
9 | GND | Ground |
10 | GND | Ground |
11 | VCC | External and Positive supply 3.3~5V |
12 | EZP_CS | Reserved for program Burning |
13 | CS | Leave Open or high level for normal working, pull low to enter sleeping mode |
14 | PTT | Module Input, Transmitting/receiving control, pull low to force the module to enter TX state; pull high for Rx state |
15 | +3.3V | 3.3V output,connect to 50mA |
16 | LINE_OUT | Audio output |
17 | T/R | Module Output, status of Transmitting/receiving, High for TX and low for Rx |
18 | SPKEN | Audio amplifier control |
19 | GND | Ground |
20 | GND | Ground |
