DSC position requests, a whole lotta beep’n going on
Geez, it’s been more than a month since I promised some entries about all the DSC testing I did, and I’ve only posted a sidetrack about my sloppy wiring. Well, let me say that I saw DSC work pretty impressively. It was easy to get and program in free MMSI numbers from BoatU.S. and Sea Tow. Then, once I got the annoying NMEA 0183 wiring straight, all four radios accepted position info from either the Raymarine E120 or the Garmin 3210. Inputing another radio’s MMSI, then placing an individual voice call, or sending a position, or asking for a position…all went well. And since I’d done a two way NMEA interface, both plotters, and a laptop running Nobeltec VNS 8, all automatically plotted those position asks or receives. Neat stuff.
But there were some hassles. One function I paid particular attention to was position requesting because that’s how Sea Smart’s interesting AVL tracking works. By default if someone requests your position each radio beeps you for a confirmation, which makes sense privacy wise. Each also lets you turn on an alternate automatic request respond mode (if you can figure where to go in the menu system). But they all still beep, and most still want an acknowledging key punch before they stop beeping! I guess the idea is that you’d want to know if someone got your position, but in the case of AVL this could become quite a beeping pain in the rear. Only the Standard Horizon GX 3000S above had a total silence option (though buried in an entirely different menu). Overall, DSC is fairly complicated to use, and pushes the limited radio interfaces to the wall. Methinks that’s partially why so few people have gotten into it, though I’d guess the main reason is that old communications gotcha — it takes two to tango. But once you and some buddies get your DSC squared away, look what it can do on, say, a Uniden 625 (here, and bigger here, showing not only your own heading but a bearing and distance to your MMSI buddy).
