Kenwood th-d72a-e Manual Do Utilizador

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6 OPERATIONAL EXAMPLES OF APRS
TH-D72A/E
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Refer to the diagram below to understand what occurs when both Decay Algorithm and Proportional 
Pathing are used at the same time.
Figure 6-3  Switching between Decay Algorithm and Proportional Pathing 
(when Stopped = 1 (knot); Moving = 3 (knots))
As the example above shows, when the mobile’s speed exceeds 3 knots, Decay Algorithm stops and 
Proportional Pathing begins.  Similarly, when the mobile’s speed drops below 1 knot, then 
Proportional Pathing stops and Decay Algorithm begins.
Note: The Stopped value cannot be configured higher than the Moving value.  Also, the Moving value cannot be configured 
lower than the Stopped value.
SmartBeaconing was developed by Mr. Steve Bragg, KA9MVA, and Mr. Tony Arnerich, KD7TA, in 
1998.  SmartBeaconing uses the speed information that is received from the GPS receiver and 
traveling direction to efficiently transmit the beacon.  There are two factors that come into play when 
determining how SmartBeaconing functions: distance traveled since last beacon transmission, 
addressed by using Variable Rate Beaconing to change the transmission interval with speed, and 
heading change since last beacon transmission, referred to as Corner Pegging.
When your mobile station is moving at a speed less than LOW SPEED as set in the menu, the 
position beacon repeatedly transmits at the interval of SLOW RATE as set in the menu.  When your 
mobile station is moving faster than HIGH SPEED as set in the menu, the position beacon repeatedly 
transmits at the interval of FAST RATE as set in the menu.  And if your mobile is traveling at any 
speed between LOW SPEED and FAST SPEED, then the beacon transmits at an interval that varies 
linearly according to the speed traveled.  The transmission interval extends longer as the speed 
becomes slower, and the interval becomes shorter as the speed gets faster.
Table 6-1  Relationship between Speed and Beacon Transmission Interval
6.1.4 Simultaneously using Decay Algorithm and Proportional 
Pathing
6.1.5 SmartBeaconing (Written by Steve Bragg, KA9MVA)
6.1.5.1 Variable Rate Beaconing (Transmission Interval Changes with Speed) 
Speed
Transmission Interval
Over HIGH SPEED
FAST RATE
Under HIGH SPEED
Over LOW SPEED
(Only when HIGH SPEED ≥ LOW SPEED)
(Only when HIGH SPEED ≥ LOW SPEED)
FAST RATE x HIGH SPEED / current speed = transmission interval time
Under LOW SPEED
SLOW RATE
Now
Proportional
Pathing
Returns
to Decay
Algorithm
Velocity (Knots)
Status
1
2
2
0
3
3
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Decay
Decay
Decay
Proportional
Proportional
Proportional
Proportional