Good Gps for moderate to dense tree cover?

[The Pineberries]

Hello there,

 

I need some advice on a good gps unit, and after spending many hours on Amazon and BassPro review sites, I thought "who better to ask than other 'catchers'".

 

Here's what I'm looking for:

 

MOST IMPORTANT: Good signal in moderate to dense tree cover. (I live in a pine forest.)

 

Good battery life, minimal of 6 hours run time.

Rugged, but it doesn't have to be water proof.

I don't want to spend more than $250.

I'd rather have buttons over touchscreen.

 

Thanks.

[+JohnCNA]

That would put you in a GPSMAP 62s. Great unit. The 64s is the other current 'button' model, but it's over your budget point.

[+GeoTrekker26]

The eTrex 20 and 30 are current and don't have a touch screen. And they are cheaper than the 62s. BUT they also use a joystick in addition to buttons which some may dislike.

[+fizzymagic]

Hello there,

 

I need some advice on a good gps unit, and after spending many hours on Amazon and BassPro review sites, I thought "who better to ask than other 'catchers'".

 

Here's what I'm looking for:

 

MOST IMPORTANT: Good signal in moderate to dense tree cover. (I live in a pine forest.)

 

Good battery life, minimal of 6 hours run time.

Rugged, but it doesn't have to be water proof.

I don't want to spend more than $250.

I'd rather have buttons over touchscreen.

 

Thanks.

 

If you want to get the best signal, I would use the Garmin 64s. Note that I do not have one so what I say is based on the specs.

 

It has:

* Quad-helix antenna (better reception than a patch antenna)

* GPS/GLONASS capability (more satellites)

* Buttons

 

So go for it.

[The Pineberries]

Thanks all! This info helped.

[+BAMBOOZLE]

That would put you in a GPSMAP 62s. Great unit. The 64s is the other current 'button' model, but it's over your budget point.

 

+1.

[snakyjake]

If you want to get the best signal, I would use the Garmin 64s...Quad-helix antenna (better reception than a patch antenna)

 

I don't think this has been proven in Garmin's handheld line, and I don't think Garmin has made the claim either. I think the 64 gives you an option of an external antenna, which I'm curious of high gain antennas.

[+BAMBOOZLE]

If you want to get the best signal, I would use the Garmin 64s...Quad-helix antenna (better reception than a patch antenna)

 

I don't think this has been proven in Garmin's handheld line, and I don't think Garmin has made the claim either. I think the 64 gives you an option of an external antenna, which I'm curious of high gain antennas.

 

Going back to 2003 every unit I have owned with a quad has outperformed my patch units esp under heavy canopy.....of late the 62 does better than my Oregon. As sussamb says there are other things involved, still I think my 60 CSx which has older hardware is better than my Oregon under canopy and I think its because of the quad.

[+Capt. Bob]

If you want to get the best signal, I would use the Garmin 64s...Quad-helix antenna (better reception than a patch antenna)

 

I don't think this has been proven in Garmin's handheld line, and I don't think Garmin has made the claim either. I think the 64 gives you an option of an external antenna, which I'm curious of high gain antennas.

 

Going back to 2003 every unit I have owned with a quad has outperformed my patch units esp under heavy canopy.....of late the 62 does better than my Oregon. As sussamb says there are other things involved, still I think my 60 CSx which has older hardware is better than my Oregon under canopy and I think its because of the quad.

 

Helix antenna radian patterns are omni-directional and therefore can be held in any orientation, which is a plus for hand held units, but this pattern makes them more susceptible to multi-path signals.

 

Patch antenna radian patterns are hemi-spherical and, when held horizontally, look skyward thus they preferentially point towards the satellites. This naturally reduces ground signal bounce.

 

It's the signal-to-noise ratio (S/N) that's important. More noise (multi-path signals) results in distorted range measurements leading to degraded navigational solutions. Making the GPSr "more sensitive" does nothing to change the S/N ratio and it’s the S/N ratio that determines the precision of the unit. Garbage in = garbage out.

[The Pineberries]

I had to read that post about six times to get all that.

Thank you, Capt. Bob, that helps , so what's a good ratio for signal to noise?

[+gpsblake]

Any GPS unit on the market is going to get you to ground zero these days. Plus consider that the person hiding the cache maybe have used an older unit that is inaccurate. So even if you have the most accurate GPS on the planet, if the geocache coords are 40 feet off, then a more accurate unit might actually cause you more DNF's because you spend too much time trusting your GPSr accuracy.

 

That being said, the Garmin 62 (and probably the 64 series might be better) is the most accurate GPS unit I have owned testing it on adjusted benchmarks.

[The Pineberries]

That's a good point, all I want is something more accurate than my old car gps.

[+Capt. Bob]

... so what's a good ratio for signal to noise?

The goal is to reduce the noise component.

 

... all I want is something more accurate than my old car gps.

We are not talking about accuracy here. Accuracy is primarily a human function and cannot be determined without a certified datum.

 

Precision, on the other hand, is equipment related. It can be compared independent of a datum by observing the size of the “rats nest” created by the track lines, over time, when held stationary. More importantly it can be quantified by calculating the variance from the mean of these track lines. When GPSrs are compared side-by-side they will share the same external influences due to uncontrollable elements such as dilution of position (DOP), noise (signal bounce), and atmospheric effects. Comparisons are valid in this situation.

 

Accuracy, or how close the track's mean is to a certified datum, depends on how well one knows, sets up and uses their equipment. When you substitute geocaches for a datum you can add “luck” to the list. Precision you can buy, accuracy you can learn, and luck comes from experience.

[+Team CowboyPapa]

.....

We are not talking about accuracy here. Accuracy is primarily a human function and cannot be determined without a certified datum.

 

Precision, on the other hand, is equipment related. It can be compared independent of a datum by observing the size of the “rats nest” created by the track lines, over time, when held stationary. More importantly it can be quantified by calculating the variance from the mean of these track lines. When GPSrs are compared side-by-side they will share the same external influences due to uncontrollable elements such as dilution of position (DOP), noise (signal bounce), and atmospheric effects. Comparisons are valid in this situation.

 

Accuracy, or how close the track's mean is to a certified datum, depends on how well one knows, sets up and uses their equipment. When you substitute geocaches for a datum you can add “luck” to the list. Precision you can buy, accuracy you can learn, and luck comes from experience.

 

Roger that, accuracy and precision have different definitions; they are not synonymous and interchangeable:

http://simple.wikipedia.org/wiki/Accuracy_and_precision

[+ecanderson]

Helix antenna radian patterns are omni-directional and therefore can be held in any orientation, which is a plus for hand held units, but this pattern makes them more susceptible to multi-path signals.

 

Patch antenna radian patterns are hemi-spherical and, when held horizontally, look skyward thus they preferentially point towards the satellites. This naturally reduces ground signal bounce.

You've inspired me, Capt Bob. Lots of text being created. However, be careful in the overall description there. A quad can either be designed as a QHO or a QHU. The "O" is as you describe .. 'omni'. The "U" in QHU stands for "uplook".

 

A QHO antenna is more sensitive out around 60 degrees and slightly less so directly overhead. Held vertically, a QHU antenna pattern is instead, VERY similar to that of a patch antenna held horizontally. BOTH are omnidirectional with regard to the horizon.

[snakyjake]

The way I remember Helix antenna advantages is within the marine environment locating satellites on the horizon and omnidirectional, and depends on which way the antenna is oriented. Also, the 62/64 has the option of an external antenna. The patch is more directional and optimized for facing up towards the sky.

 

I think in practical use under tree cover you have a few satellites, weak signals, coming through the trees directly overhead. I gather from Garmin's statement the weak link is no longer the antenna nor the GPS receiver. I am now more focuses on more satellites, and hopefully higher power transmission of a signal or different frequency.

[+Capt. Bob]

.....

We are not talking about accuracy here. Accuracy is primarily a human function and cannot be determined without a certified datum.

 

Precision, on the other hand, is equipment related. It can be compared independent of a datum by observing the size of the “rats nest” created by the track lines, over time, when held stationary. More importantly it can be quantified by calculating the variance from the mean of these track lines. When GPSrs are compared side-by-side they will share the same external influences due to uncontrollable elements such as dilution of position (DOP), noise (signal bounce), and atmospheric effects. Comparisons are valid in this situation.

 

Accuracy, or how close the track's mean is to a certified datum, depends on how well one knows, sets up and uses their equipment. When you substitute geocaches for a datum you can add “luck” to the list. Precision you can buy, accuracy you can learn, and luck comes from experience.

 

Roger that, accuracy and precision have different definitions; they are not synonymous and interchangeable:

http://simple.wikipedia.org/wiki/Accuracy_and_precision

 

A cross-eyed cowboy, with the finest rife ever made, will miss the coyote everytime...unless he gets lucky.

[+Capt. Bob]

Helix antenna radian patterns are omni-directional and therefore can be held in any orientation, which is a plus for hand held units, but this pattern makes them more susceptible to multi-path signals.

 

Patch antenna radian patterns are hemi-spherical and, when held horizontally, look skyward thus they preferentially point towards the satellites. This naturally reduces ground signal bounce.

You've inspired me, Capt Bob. Lots of text being created. However, be careful in the overall description there. A quad can either be designed as a QHO or a QHU. The "O" is as you describe .. 'omni'. The "U" in QHU stands for "uplook".

 

A QHO antenna is more sensitive out around 60 degrees and slightly less so directly overhead. Held vertically, a QHU antenna pattern is instead, VERY similar to that of a patch antenna held horizontally. BOTH are omnidirectional with regard to the horizon.

 

Both antennas have a vertical portion to their radiation pattern. They also have a back lobe portion too. It’s the ground plane that terminates this back lobe portion. The ground plane for patch antennas is easily manufactured, small and very effective. It is more difficult for helical antennas. I’m not sure if the GPS units in questions employ a ground plane. They may just rely on the ground bounce mis-matched polarization to degrade these unwanted signals. Just speculating here.

[Pacific NW]

Lots of great info in this thread!

 

Being in the NW, we have plenty of trees. Running a GPSMAP 64ST here. Seems to do well in heavy cover. For $249 MSRP, you could get the base-model GPSMAP 64. It is lacking the electronic compass and barometric altimeter of the fancier models, but adds in Russian GLONASS system reception. Depending on where you are located, that can be a nice boost, especially if you're in the northern latitudes. One other nice perk of the 64-series is that they can hold a LOT of caches: LINK.