DOWNLOAD complete documentation, parts and distributers (70cm UHF Transceiver with DRA818U Module.pdf)
DOWNLOAD schematic 70cm UHF Transceiver with DRA818U Module (EAGLE .sch)
DOWNLOAD  Software 70cm UHF Transceiver with DRA818U Module  (TRCV.zip)

Below you find a photo of my homemade transceiver for the 70 cm amateur radio band. This small circuit incoporates a small narrow band transmitter and receiver for 400 MHz to 470 MHz with an output power of 1 W. The microcontroller  feeds the Dorji module with transmit-, receiver-, bandwidth- and squelch information via a serial telegram. All what is needed is a microphone, speaker, PTT an some power from a single lithium-Iion cell.  See full documentation link above.

Figure 1: Photo 70cm UHF Transceiver with DRA818U Module                                                  




Figure 2: Schematic 70cm UHF Transceiver with DRA818U Module