<div>Hmmm... just a difference of opinion. I wrote a program a few years ago to emulate smart beaconing on my laptop. It showed me when it wanted to beacon and for what reason. I drove around watching it and tweaking it to provide a useful track but not qrm too much.... and so starts my explaination....</div>
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<div>There seems to be much misunderstanding about how to optimize smart beaconing.... and i'm sure there are many opinions... everyone has one, right?</div>
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<div>Smart beaconing has three modes.... slow(time triggered) , meduim (turn triggered), and fast (distance triggered)</div>
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<div>For driving a car, I prefer the following behavors....</div>
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<div>When I am parked beacon at a reduced rate. This is time triggered.</div>
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<div>When I _intentionally_ turn off a highway or main road I want a beacon to mark my turn.... This is turn triggered. </div>
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<div>Once I reach a speed that is too high to turn (let's say 45mph / 70kph ) , I want a bread crumb every mile or two. I do not want to corner peg the long slow turns on the highway or interstate. The home audience can figure out on their own that there is no opportunity for me to exit the interstate on that last long slow turn. The most aggrivating is the slow S turn... the road slowly veers to the left then back to the right. If your tracker is setup improperly, it will beacon twice 1/2 a mile apart.... not what we want.</div>
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<div>I tend to run fast beacon speed just below the lowest speed I "cruise" at on the interstate or main highway. If you set it too high (ie 90mph), smart beaconing uses turns to trigger all the time. You will never enter the distance triggered mode. As I said this is sometimes troublesome on long sweeping turns on the interstate. </div>
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<div>The long slow turn is also an issue when you don't quite break out of the meduim speed mode and into fast speed beaconing... the turn threshold narrows up as speed increases thus it will trigger on a 10° snake in the road at 60mph , and won't trigger on a 45° turn in a parking lot (if the turn slope setting is wrong). Not to keep beating this horse, but you want to set the turn min so that it triggers on huge turns when you are moving 5 to 10mph, but don't set the turnslope so aggressive that it narrows up too quickly and triggers on 1 degree turns at 30mph. (exagerated to make a point). </div>
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<div>As I said, in my opinion, ideally you want to run turn triggered (medium speed beacon mode) when you are a)moving, b)but at a speed that is slightly below the speed you would cruise at. At any speed that you don't consider it safe to turn off the highway, make that your fast beacon speed. Then adjust the time to beacon every mile or two at that speed.</div>
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<div>The thing to remember is that we want quality of positions above quantity. Turn triggered beacons provide excellent info. But we do not need to neatly trace the exact contours of the interstate or that winding two lane road from the suburbs into the city. But it is nice to know which street I turned down in a residential neighborhood when there are streets every 200 feet.</div>
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<div>Wes<br><br></div>
<div class="gmail_quote">On Mon, May 19, 2008 at 10:02 PM, Rory Burke <<a href="mailto:rory@burke.ac">rory@burke.ac</a>> wrote:<br>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">I'd like to see the High Speed parameter for SmartBeaconing increased from 70 to something higher - at least 90, and the Fast Rate increased to something like 300 seconds. If you spend some time analyzing the SmartBeaconing algorithm you will find that the real beauty of it is that you can decided how far apart in distance traveled you want to send beacons. But the High Speed limit defeats that thinking if it is lower than the highest speed you travel. You see, once you reach the High Speed, the beacons always come at the Fast Rate. That means that once you are exceeding the High Speed the distance traveled between beacons becomes longer and longer. Here's an example:<br>
<br>Low Speed = 2 mph<br>High Speed = 60 mph<br>Slow Rate = 30 minutes<br>Fast Rate = 60 seconds<br><br>You will send a beacon at one mile intervals once you exceed 2 mph until you reach 60 mph. But if you are in one of those places where 75 mph is safe and legal, you'll be sending beacons at 1-1/4 mile intervals.<br>
<br>Now take a look at this example:<br><br>Low Speed = 2 mph<br>High Speed = 90 mph<br>Slow Rate = 30 minutes<br>Fast Rate = 40 seconds<br><br>In this example you will send a beacon at one mile intervals until you reach 90 mph; a speed that is not normally safe or legal - at least in most places in the US. In this case, you travel 1/8 mile for every 5 seconds of Fast Rate. So, if you wanted your beacons 2 miles apart you'd select a Fast Rate of 80 seconds, and if you wanted 5 mile beacon spacing you'd select a Fast Rate of 200 seconds. The distance traveled between beacons would not change from what you've set unless you exceed 90 mph.<br>
<br>I am aware that most folks who use SmartBeaconing are still in the "how often am I sending a beacon" mindset rather than the "how far do I travel between beacons" mindset. I believe that if folks would take a hard look a the algorithm, and read the SmartBeaconing description on the HamHUD web site they would see that the real intent is the "how far" mindset. Please note that the third paragraph of the SmartBeaconing description has an error. It omits the fact that if the High Speed threshold is exceeded, then the positions are sent at the Fast Rate no matter how much faster you travel. Here's a link to the description:<br>
<br><a href="http://www.hamhud.net/hh2/smartbeacon.html" target="_blank">http://www.hamhud.net/hh2/smartbeacon.html</a><br><br>These changes would take a fairly simple firmware tweak the next time there's an update.<br>
<br>73 - Rory - K5MBH<br><br><a href="mailto:rory@burke.ac" target="_blank">rory@burke.ac</a> <a href="mailto:k5mbh@arrl.net" target="_blank">k5mbh@arrl.net</a><br><br>Where am I now?<br><a href="http://map.findu.com/k5mbh-9" target="_blank">http://map.findu.com/k5mbh-9</a><br>
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</blockquote></div><br><br clear="all"><br>-- <br>Wes<br>---<br>Where there's silence, there is no Hope.