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Impressed with the Etrex Legend


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Im kinda new to all of this so forgive some of the terminology.

 

Im sitting inside of my house and recieving a signal from 9 satelites. I have obtained and accuracy of 8 feet. I have marked a waypoint, translated the coordinates and put the Longitude and Latitude into Microsoft Mappoint. It nailed it right on the head. I was worried about reception while in the woods and here im getting great reception from inside my house.

 

Pretty good, I think

 

Tom

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You may find the signal will degrade under trees because trees absorb microwave signals.

 

If you have a Direct TV or satellite dish they will always require a clear path to the satellite. If you place it behind a tree the signal will degrade to the point of loss. Same concept with a GPS. The thicker the foliage the less signal you will receive.

 

The roof is another story. icon_rolleyes.gif Plywood and all the stuff on top of it won't stop a microwave. icon_smile.gif My local antennia is in the attic. Yea, the signal is not as good as if it was outside the roof but, the antennia is protected from the weather.

 

So, trees absorb microwaves, roofs don't (well at least not as much as trees).

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You may find the signal will degrade under trees because trees absorb microwave signals.

 

If you have a Direct TV or satellite dish they will always require a clear path to the satellite. If you place it behind a tree the signal will degrade to the point of loss. Same concept with a GPS. The thicker the foliage the less signal you will receive.

 

The roof is another story. icon_rolleyes.gif Plywood and all the stuff on top of it won't stop a microwave. icon_smile.gif My local antennia is in the attic. Yea, the signal is not as good as if it was outside the roof but, the antennia is protected from the weather.

 

So, trees absorb microwaves, roofs don't (well at least not as much as trees).

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quote:
Originally posted by Vertigo:

No

 

quote:
Originally posted by Alan2:

Could it be that trees and leaves that are naturally filled with water act as a natural ground directing radio signals to that area?

 

Alan



 

Thanks. You're explanation really cleard that up for me. Alan. icon_confused.gif

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quote:
Originally posted by Vertigo:

No

 

quote:
Originally posted by Alan2:

Could it be that trees and leaves that are naturally filled with water act as a natural ground directing radio signals to that area?

 

Alan



 

Thanks. You're explanation really cleard that up for me. Alan. icon_confused.gif

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Getting Back On Subject, I can generally get several birds inside my house. I suspect some signals are being reflected off walls, etc. However, outside, I rarely have a reception problem with my Legend. Even under tree cover doesnt seem to be a big problem. So far, I can remember only once where I lost reception on a cache hunt but I got the signal back as soon as I moved a ways.

 

compass.gif

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The water doesn't "direct" the radio waves, it just basicaly absorbs it.

 

Radio waves are just like light waves, nothing (aside from mass, i.e. a black hole) can bend or suck them towards it. The only way the tree can block the signal is if it's within the line of sight from you to the satellite.

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quote:
Originally posted by Vertigo:

The water doesn't "direct" the radio waves, it just basicaly absorbs it.

 

Radio waves are just like light waves, nothing (aside from mass, i.e. a black hole) can bend or suck them towards it. The only way the tree can block the signal is if it's within the line of sight from you to the satellite.


 

Sorry to be a stickler, but I wanted to point out that light and radio waves, both being forms of electromagnetic radiation, do "bend" for reasons other than gravity.

 

Without going into quantum electro dynamics, EMR travels at different speeds through different media (ex. warm air vs. cold air, vacuum vs. atmosphere). And, for reasons we do not understand, photons, the quanta, or smallest divisable 'chunk', of EMR, seem to have the ability to sniff out the best route to a destination (sub atomic GPS units and cell phones?) Photons also, for lack of a better word, require 'elbow room'.

 

We can predict these behaviors using a complicated system of probability summation, but the effect is not limited to some laboratory anomally. You can often see it in every day life.

 

One of the best examples is the common road mirage often seen while driving in western states. It really does look like water on the road. This happens when the air just above the road is warm, but the surrounding air is cool. You are actually looking at part of the sky at road level. The photons take a curved path from the sky, down to the roadway, travel in the 'fast lane' (the warm air above the road), then curve back to your eye. Since we normally only see the sky from the ground as a reflection in water, our brain fills in the rest. The moving edges of the mirage are the moving air currents between the warm and cool air.

 

At normal radio wavelengths bending and twisting due to atmospheric conditions can be quite severe.

 

Again, sorry to be a stickler... icon_smile.gif

 

-jjf

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quote:
Originally posted by Vertigo:

The water doesn't "direct" the radio waves, it just basicaly absorbs it.

 

Radio waves are just like light waves, nothing (aside from mass, i.e. a black hole) can bend or suck them towards it. The only way the tree can block the signal is if it's within the line of sight from you to the satellite.


 

Sorry to be a stickler, but I wanted to point out that light and radio waves, both being forms of electromagnetic radiation, do "bend" for reasons other than gravity.

 

Without going into quantum electro dynamics, EMR travels at different speeds through different media (ex. warm air vs. cold air, vacuum vs. atmosphere). And, for reasons we do not understand, photons, the quanta, or smallest divisable 'chunk', of EMR, seem to have the ability to sniff out the best route to a destination (sub atomic GPS units and cell phones?) Photons also, for lack of a better word, require 'elbow room'.

 

We can predict these behaviors using a complicated system of probability summation, but the effect is not limited to some laboratory anomally. You can often see it in every day life.

 

One of the best examples is the common road mirage often seen while driving in western states. It really does look like water on the road. This happens when the air just above the road is warm, but the surrounding air is cool. You are actually looking at part of the sky at road level. The photons take a curved path from the sky, down to the roadway, travel in the 'fast lane' (the warm air above the road), then curve back to your eye. Since we normally only see the sky from the ground as a reflection in water, our brain fills in the rest. The moving edges of the mirage are the moving air currents between the warm and cool air.

 

At normal radio wavelengths bending and twisting due to atmospheric conditions can be quite severe.

 

Again, sorry to be a stickler... icon_smile.gif

 

-jjf

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