GD-77 FCC Certification

| diciembre 11, 2017

GD-77 FCC Certification

GD-77 was a DMR Digital Transceiver, which was measured approximately: 3.4 cm (L) x 6.1 cm (W) x 13.3 cm (H), DC7.4V from Battery or DC 12V from adapter.


Applicable Standards: TIA-603-D.

Measurement Uncertainty

Parameter Measurement Uncertainty
Occupied Channel Bandwidth ±5 %
RF output power, conducted ±0.61dB
Unwanted Emissions, radiated 30MHz ~ 1GHz:5.85 dB 1G~26.5GHz: 5.23 dB
Unwanted Emissions, conducted ±1.5 dB
Temperature ±1C
Humidity ±5%
DC and low frequency voltages ±0.4%
Duty Cycle 1%

UT Description DMR Digital Transceiver Tested Model GD-77

MODE Max. SAR Level(s) Reported(W/kg) Limit
PTT(136-174 MHz) 1g Head SAR(Face Up) 0.46 8.0 (W/kg)
1g Body SAR(Body Back) 1.66
PTT(400-470 MHz) 1g Head SAR(Face Up) 2.75
1g Body SAR(Body Back) 3.85

Applicable Standards

ANSI / IEEE C95.1 : 2005

IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fileds,3 kHz to 300 GHz.

ANSI / IEEE C95.3 : 2002

IEEE Recommended Practice for Measurements and Computations of Radio Frequency Electromagnetic Fields With Respect to Human Exposure to SuchFields,100 kHz—300 GHz.

FCC 47 CFR part 2.1093

Radiofrequency radiation exposure evaluation: portable devices


IEEE Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Head from Wireless Communications Devices: Measurement Techniques

IEC 62209-2:2010

Human exposure to radio frequency fields from hand-held and body-mounted wireless communication devices-Human models, instrumentation, and procedures-Part 2: Procedure to determine the specific absorption rate (SAR) for wireless communication devices used in close proximity to the human body (frequency range of 30 MHz to 6 GHz)

KDB procedures

KDB 447498 D01 General RF Exposure Guidance v06 KDB 865664 D01 SAR Measurement 100 MHz to 6 GHz v01r04 KDB 865664 D02 RF Exposure Reporting v01r02 KDB 643646 D01 SAR Test for PTT Radios v01r03

Note: This wireless device has been shown to be capable of compliance for localized specific absorption rate (SA for Occupational/Controlled Exposure limits specified in FCC 47 CFR part 2.1093 and has been tested in accordance with the measurement procedures specified in IEEE 1528-2013 and RF exposure KDB procedures.

Technical Specification

Device Type: Portable
Exposure Category: Occupational/Controlled Exposure
Antenna Type(s): External Antenna
Body-Worn Accessories: Belt Clip
Face-Head Accessories: None
Operation Mode : PTT_FM, PTT_4FSK
Frequency Band: PTT_FM/PTT_4FSK: 136 -174 MHz, 400 -470 MHz
Conducted RF Power:
  • PTT FM 136 -174 MHz: 4.99 W
  • PTT 4FSK 136 -174 MHz: 4.98 W 
  • PTT FM 400 -470 MHz: 4.99 W 
  • PTT_4FSK 400 -470 MHz: 4.95 W
Dimensions (L*W*H): 3.4 cm (L) x 6.1 cm (W) x 13.3 cm (H)
Power Source: 7.4 VDC Rechargeable Battery
Normal Operation: Face Up and Body-worn

Chip View

AT1846S chip integrates all the circuitry of a radio transceiver V-UHF; all in there. For digital audio DMR with AMBE vocoder has the HR-C6000 processor; and to control all functions of the equipment, process, etc; It is the ARM MK22FN512VLL12. Something similar to what is in our phones, or own Raspberry Pi.
This computer communicates directly by USB, since ARM has USB interface. If you want to make the cable…

GD-77 Downloads



ARM® Cortex®-M4 Kinetis K20 Microcontroller IC 32-Bit 120MHz 512KB (512K x 8) FLASH 100-LQFP (14×14)

Radioddity GD-77 Firmware and CPS v2.6.9 and CPS v1.1.13
Radioddity GD-77 MANUAL


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