[{"data":1,"prerenderedAt":137},["ShallowReactive",2],{"article-cessna172-radio-stack":3},{"id":4,"title":5,"body":6,"description":126,"downloads":127,"extension":128,"lastUpdated":129,"meta":130,"navigation":131,"path":132,"readingTime":133,"seo":134,"stem":135,"__hash__":136},"projectArticles\u002Fprojects\u002Fcessna172\u002Fradio-stack.md","Radio Stack",{"type":7,"value":8,"toc":117},"minimark",[9,14,18,21,25,77,81,84,100,103,107,110,114],[10,11,13],"h2",{"id":12},"overview","Overview",[15,16,17],"p",{},"The radio stack in the 172SP G1000 sits in the lower centre of the instrument panel. It consists of the GMA 350 audio panel at the top, followed by the COM1\u002FNAV1 and COM2\u002FNAV2 heads, and the GTX 345 transponder at the bottom.",[15,19,20],{},"In a G1000-equipped aircraft the radio heads are largely redundant with the G1000's own COM\u002FNAV tuning, but they are retained for their physical presence and the satisfying tactile feel of tuning a radio with a real knob.",[10,22,24],{"id":23},"components","Components",[26,27,28,41],"table",{},[29,30,31],"thead",{},[32,33,34,38],"tr",{},[35,36,37],"th",{},"Unit",[35,39,40],{},"Function",[42,43,44,53,61,69],"tbody",{},[32,45,46,50],{},[47,48,49],"td",{},"Garmin GMA 350",[47,51,52],{},"Audio panel — intercom, marker beacon, speaker\u002Fheadset routing",[32,54,55,58],{},[47,56,57],{},"COM1\u002FNAV1",[47,59,60],{},"Primary comm and nav radio head",[32,62,63,66],{},[47,64,65],{},"COM2\u002FNAV2",[47,67,68],{},"Secondary comm and nav radio head",[32,70,71,74],{},[47,72,73],{},"GTX 345",[47,75,76],{},"Mode S transponder with ADS-B",[10,78,80],{"id":79},"build-approach","Build Approach",[15,82,83],{},"Each radio unit is a 3D-printed replica housing with:",[85,86,87,91,94,97],"ul",{},[88,89,90],"li",{},"LCD display (small I²C OLED or custom PCB)",[88,92,93],{},"Concentric rotary encoders for frequency tuning (coarse\u002Ffine)",[88,95,96],{},"Pushbutton for frequency flip-flop",[88,98,99],{},"Arduino Nano or Pro Mini per unit",[15,101,102],{},"Frequency data is read from X-Plane datarefs via CockpitConnect and sent to the displays. Encoder inputs write back to the same datarefs through the CockpitConnect bridge.",[10,104,106],{"id":105},"audio-panel","Audio Panel",[15,108,109],{},"The GMA 350 replica has toggle switches for COM1\u002FCOM2\u002FNAV1\u002FNAV2 audio routing and a speaker button. These map to X-Plane audio routing datarefs.",[10,111,113],{"id":112},"status","Status",[15,115,116],{},"Planning — no physical work started yet.",{"title":118,"searchDepth":119,"depth":119,"links":120},"",2,[121,122,123,124,125],{"id":12,"depth":119,"text":13},{"id":23,"depth":119,"text":24},{"id":79,"depth":119,"text":80},{"id":105,"depth":119,"text":106},{"id":112,"depth":119,"text":113},"Build log for the Cessna 172SP radio stack — GMA 350 audio panel, COM\u002FNAV heads, and GTX 345 transponder.",null,"md","2026-03",{},true,"\u002Fprojects\u002Fcessna172\u002Fradio-stack",4,{"title":5,"description":126},"projects\u002Fcessna172\u002Fradio-stack","sg-bzn7xl0-uoTzCdMgpjty1GMouLvvb02VWkxdLqVY",1781294861972]