[aprssig] A wish for the next TM-D710A firmware update
Rory Burke
rory at burke.ac
Tue May 20 09:35:19 EDT 2008
On May 20, 2008, at 7:31 AM, Charles Gallo wrote:
>
>
> On 5/19/2008 Rory Burke wrote:
>
>> I'd like to see the High Speed parameter for SmartBeaconing increased
>> from 70 to something higher - at least 90,
>
> Me thinks someone lives out west - 90? The last time any of my
> vehicles saw 90 mph was (thinking...) 23 years ago. For that
> matter, I can probably count the number of times I've had a vehicle
> up above 80 for a sustained period of time on one hand, and have
> digits left over. Heck, unless you are on the Thruway around here,
> you'll rarely see 70. (Most roads around here have a 50 or 55 mph
> speed limit - and on some of them it's STRICTLY enforced - the local
> 3 lane in each direction highway that has minimal traffic.. 50 mph
> - and if it's when they are out enforcing - don't be doing 55 - they
> WILL ticket you - speed trap)
If you'll go back and read my post again, and then think about
DISTANCE based beaconing rather than time based beaconing, you might
see that the High Speed needs to be a speed that you would not
normally ever reach. Once you reach the High Speed, SmartBeaconing
reverts to time based beaconing. If your goal is to know that you'll
send a beacon every X miles while moving, no matter how fast or slow
you're driving, then you need to be able to set the High Speed higher
than the speed limit. Using 90 mph makes for some easy in-the-head
calculations about how to set the beacon rate based on the distance
between beacons you desire. The Fast Rate needs to be higher as
well. With a limit of 180 seconds, you're limited to 4-1/2 miles
between beacons. On a long interstate trip that's probably too close
together. Changing that parameter limit to 400 seconds would allow
you to beacon every 8 miles. That's assuming that you're using 90 mph
as the High Speed.
73 - Rory - K5MBH
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