Mobile | DMR


diagram indicating highlights of HM655

Reliable Communication

Can deliver clear and dependable communications in areas where the signal is unstable or weak.

Wireless Connection

It can work with BT audio accessories to boost safety and productivity during in-vehicle communications.

Superior Durability

It withstands harsh temperatures, shock, and vibration, and meets MIL-STD-810G standards, and IP54 for dust and water intrusion.

On/Off Button

Remote Speaker Microphone with Display and Limited Keypad

to fully control the HM655, turn it on or off, switch channels or contacts, adjust the volume, or view messages.

Aviation Connector and Curly Cord

Strong and secure 10 pin aviation connector and curly cord with excellent stretching ability.


Created with Sketch. Reliable Communication

Thanks to the high RX sensitivity, the HM655 can deliver clear and dependable communication even in areas where the signal is weak or unstable.

StayConnected-0x20 Wireless Connection

With the built in BT 5.0 module*, the HM655 can work with the BT audio accessories to boost your safety and productivity during in-vehicle communication.*Please be advised that this feature is applicable to the BT HM655 version only

Created with Sketch. Handheld Control Head

The HM655 has a convenient Speaker microphone that has a display and controls which can be mounted in close proximity and allow you to turn on or off the radio, switch channels or contacts, adjust the volume.

MIL-STD-20x20 Superior Durability

The HM655 withstands harsh temperatures, shock, vibration and meets the MIL-STD-810G standards. The device also features an IP54 rating against dust and water intrusion. The connection between the palm microphone and the 10-pin aviation connector is very secure preventing it from becoming loose. The palm microphone cord has excellent stretching ability to protect it thus giving the maximum service life.

Accessories for HM655

Included as standard with HM655 Included as standard with HM655


Charger & Power




Related products that work with the HM655

Technical Specifications


Frequency range
UHF: 400-470 MHz
VHF: 136-174 MHz
Channels & zones
Channel capacity: 512
Zone capacity: 16
Channel spacing analogue
Channel spacing digital
Operating voltage
13.6 V DC ±15%
Current drain
standby: <0.5 A
receive: <2.0 A
transmit 5W: <4 A
transmit 25W: < 8 A
transmit 45W: <12 A
Frequency stability
±0.5 ppm
Antenna impedance
50 Ohm
Dimensions (H x W x D)
164 x 154 x 42 mm
Digital protocol
ETSI-TS102 361-1,-2,-3


Analogue: 0.18µV (12dB SINAD)
Analogue: 0.16µV (12dB SINAD) (typical)
Digital: 0.18µV / BER 5%
TIA-603: 65dB @12.5kHz / 75dB @20/25kHz
ETSI: 50 dB @12.5kHz / 70dB @20/25kHz
TIA-603: 75dB @12.5/20/25kHz
ETSI: 70dB @12.5/20/25kHz
Spurious Response Rejection
TIA-603: 75dB @12.5/20/25kHz
ETSI: 70dB @12.5/20/25kHz
TIA-603: 90 dB
ETSI: 84 dB
Hum and Noise
40dB @12.5kHz; 43dB @20kHz; 45dB @25kHz
Rated Audio Power Output
internal (20 Ohm load): 3W
external (8 Ohm load): 6W
Max Audio Power Output
internal (20 Ohm load): 7.5W
external (8 Ohm load): 20W
Rated Audio Distortion
Audio Response
+1 to -3 dB
Conducted Spurious Emission
< -57 dBm


RF Power Output
Low Power model: 5-25 W
High Power model: 5-45 W (UHF); 5-50 W (VHF)
FM Modulation
11K0F3E @12.5kHz
14K0F3E @20kHz
16K0F3E @25kHz
4FSK Digital Modulation
12.5kHz data only: 7K60FXD
12.5kHz data and voice: 7K60FXW
Conducted/Radiated Emission
-36dBm @<1GHz; -30dBm @>1GHz
Modulation Limiting
±2.5kHz @12.5kHz; ±4.0kHz @20kHz; ±5.0kHz @25kHz
FM Hum and Noise
40dB @12.5kHz; 43dB @20kHz; 45dB @25kHz
Adjacent Channel Power
60dB @12.5kHz; 70dB @20/25kHz
Audio Response
+1 to -3 dB
Audio Distortion
Digital Vocoder Type


Operating temperature
-30°C to +60°C
Storage temperature
-40°C to +85°C
IEC 61000-4-2 (level 4)
+8kV (contact); +15kV (air)
American Military standard
Dust & water protection
per MIL-STD-810G standard
Shock and vibration
per MIL-STD-810G standard


TTFF (time to first fix) cold start
< 1 minute
TTFF (time to first fix) hot start
< 10 seconds
Horizontal accuracy
< 5 meters