Thread: Digital Radio
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Old 11-18-2013, 02:27 PM
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DaveInDenver DaveInDenver is offline
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The other station's location is just shown relative to yours. IOW, a compass heading. None of these radios have maps like you're used to with GPS devices.

You can send a stream of GPS data out of the serial ports which is then potentially displayed on an external device (computer, tablet, etc.). I use a Garmin Nuvi 350 with my FTM-350 and all the APRS beacons show as waypoints on the map and in the list of navigable places, like they are McDonald's or something. If I punch another station as a waypoint the Nuvi calculates the way to get there on existing roads from it's base map. Depending on my zoom level any station beacons I hear also show up as dots on the map. That is the quasi-tactical nature of it.

With digital radios the voice and data is converged onto one channel where as with APRS it's a whole second system with different repeaters, different paths. That is fine but it's nice to know that your digital information is making it or not by knowing if you're in range via voice.

However, when you chose not to do voice and data with the FTM-400, IOW the total bandwidth is dedicated to voice, it still embeds your call sign at the beginning of the voice stream. I think this is the same case with ICOM digital radios, it shoves the call sign onto the voice-only stream. This is partially necessary with these protocols, since your call sign substitutes for the radio ID. Commercial digital systems require all the radios to have identifiers registered to them, but ham being decentralized does it differently. As long as you have a call sign and not nulls in the stream you get included in the registry.

Then it displays on other people's radios, although that's really not the whole of it. The reason they do this is when you connect to a digital repeater adding that call sign data will change your status in the linked (over the Internet mostly) gateway databases and if someone was watching for you to key up it would notify them and they could call you. It's like combining IRLP and APRS functions in a sense, but automagically.
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