Dorji DRA808M
The Dorji DRA808M is a 70cm band (400-470MHz) FM (analog) radio transceiver module with a 1W maximum output power. The radio measures 84mm x 48mm x 25mm (3.3" x 1.9" x 1"). It can be purchased from Tindie for $17.00 USD, incl. shipping. The module datasheet can be found here.
Comments
Testing
All tests done at 445.925MHz
Power:
- High = xW
- Low = xW
Carrier Frequency Deviation:
- xHz (Narrow, Approx.)
Deviation:
- xkHz (Narrow, Approx.)
- xkHz (Wide, Approx.)
- xHz (PL Deviation, Wide, Approx.)
Receiver Sensitivity:
- xuV (Approx.)
Current (At 3.7V):
- RX Idle = xmA
- RX Active (Squelch Open) = xmA
- TX Low Power = xmA
- TX High Power = xA
Weight:
- DRA808M with no shield can = 2.2g
- DRA808M with shield can = 3.4g
Component List
Component | Part Marking/Additional Text | Manufacturer | Function |
RDA1845 | UB141150 | RDA - RDA1845 | Single chip transceiver, integrating synthesizer, IF selectivity and base-band signal processing. 10mW Output power. |
TMS370C002A(?) | 0C002 B0C7 | Unknown | 8-Bit microcontroller |
2SC3356 | R25 | NEC | NPN Transistor |
Unknown | W D | Unknown | Transistor (Power Amplifier) |
SGM2019-3.0YN5 | YJ30 | SG Micro | 3.0V LDO |
SJK-6U-14.74569-10-80-A-15 | SJK 14.7456 | Q-Crystal | XTAL for Microcontroller |
28.00 | 28.00P D150 | Unknown | XTAL for RDA1845 |
I have acquired the datasheet for the main radio IC, RD1845, and interestingly, the comment posted on the forum with the datasheet download was the following: "Radio chip, the transceiver has a lot of indicators can not meet the national standard! Careful use!" The datasheet can be found here: http://rev0proto.com/files/RDA1845_datasheet_v1.1e.pdf Additionally, the registers and programming info can be found here (for more adventurous hackers): http://rev0proto.com/files/RDA1845_registers_v2.3.pdf