Block diagram is from: "Figure 2: Two Channel VHF Base Station," Planning Emergency Medical Communications: Volume 2, Local/Regional Level Planning Guide, (Washington, D.C.: National Highway Traffic Safety Administration, US Department of Transportation, 1995) pp. 42. The word "antenna" was added to the original so that those unfamiliar with the schematic symbol for an antenna could see what's going on. A spelling error in the original diagram was corrected, and an extra arrow was removed from the SVG version.
Redrawn from Base station 2 channel block diagram.png
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