JT4 Data on the UKµWG Reverse DDS Module - G4JNT
JT4 Data on the UKµWG Reverse DDS Module - G4JNT
JT4 Data on the UKµWG Reverse DDS Module - G4JNT
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The 7805 regulator in <strong>the</strong> R<strong>DDS</strong> module has sufficient spare capability to supply <strong>the</strong> 100 – 200mAneeded by most GPS receiver modules that take a +5V input, although users may have to beaware of any additi<strong>on</strong>al heat sinking requirements that may be necessary.The descripti<strong>on</strong> that follows, as well as <strong>the</strong> PIC firmware supplied, assumes that serial data in <strong>on</strong>eof two formats is available. The proprietary binary format given by <strong>the</strong> Motorola Oncore or M12type GPS module at 9600 baud or standard NMEA text messages at 4800 baud. The polarity of<strong>the</strong> data can be selected at <strong>the</strong> time <strong>the</strong> PIC firmware is compiled. Ei<strong>the</strong>r native 5V logic orRS232 polarity can be catered-forAt <strong>the</strong> time of writing, suitable Oncore GPS receiver modules are available from [2] Note thatthis family of modules can be commanded to supply data in NMEA format, but given <strong>the</strong> choice,<strong>the</strong> binary versi<strong>on</strong> is preferable.Figure 1 shows <strong>the</strong> interface c<strong>on</strong>necti<strong>on</strong>s, specifically for <strong>the</strong> Oncore <strong>Module</strong> with its 10 pinheader, and includes an additi<strong>on</strong>al red/green LED for fr<strong>on</strong>t panel mounting.<str<strong>on</strong>g>JT4</str<strong>on</strong>g> for R<strong>DDS</strong> <strong>Module</strong> <strong>G4JNT</strong> Page 2