Buying a GPS for heavily wooded areas

[+Joshdent]

Hello everyone!

 

I used to geocache years ago, and I am ready to start again, introducing my 4 year old son to geocaching. I need to purchase a GPS model, and I am so confused- one website rates model "X" 5 stars, and the other website rates it 2 stars. I am looking for more of an entry level model- spending around $200. I will be using it exclusively for geocaching. My big concern is where I am most of the geocaching is done in the woods. Years ago I had a rudimentary eTrex that was great at the beach, but then under heavy tree cover didn't register at all, and got me very frustrated. I would appreciate if anyone has suggestions of a great entry level model perfect for geocaching that is strong at picking up signal under heavy cover. Thanks!

[+BlackRose67]

I have an eTrex 20 and use it in heavily wooded areas at times.

 

For me, the extra set of satellites, in this case GLONASS, helps quite a bit.

 

You will not get perfect reception, but I believe it helps compared to just having the GPS satellites.

[+wmpastor]

I have an eTrex 20 and use it in heavily wooded areas at times.

 

For me, the extra set of satellites, in this case GLONASS, helps quite a bit.

 

You will not get perfect reception, but I believe it helps compared to just having the GPS satellites.

In other words, both gpsr's & smartphones have improved quite a bit inthe last five years.

[+Glenn]

I'm not going to recommend a specific make or model but I am going to tell you want to look for. You want to look for SiRFstarIII in the specs of the GPSr. You'll often see GPSrs with that chipset and similar chipsets marketed as high sensitivity. Also look for GPSrs with a Quadrifilar Helix Antenna (QFHA).

[tr_s]

You want to look for SiRFstarIII in the specs of the GPSr.

 

Sirfstar 3 was market leading a few years ago. Nowadays it is actually inferior in sensitivity compared to most new chipsets from for instance Mediatek, or the Teseo in the new eTrex series.

There are however, apparently, new Sirf chipsets (4 and 5).

 

Anyway, what the original poster is looking for is both a sensitive receiver and a large selective antennae. If on a budget, only the first one is okay.

The new eTrex series for instance (10/20/30) has a very sensitive receiver, but I have unfortunately seen it to be rather prone to multipath problems. Probably, the rather small quite omnidirectional antenna filament in conjunction with the extremely sensitive receiver hears any reflection from a mountain wall almost as good as the direct LOS signal from the satellites. This, however, might not pose a problem at all to the original poster depending on use; also, switching Glonass on is said to help away multipath issues.

[+Redwoods Mtn Biker]

As long as it has a high-sensitivity GPS chipset (and most released in the last few years do), you should be fine.

[+Glenn]

You want to look for SiRFstarIII in the specs of the GPSr.

 

Sirfstar 3 was market leading a few years ago. Nowadays it is actually inferior in sensitivity compared to most new chipsets from for instance Mediatek, or the Teseo in the new eTrex series.

There are however, apparently, new Sirf chipsets (4 and 5).

 

 

That's why I followed it with "and similar chipsets". With all the variety out there nowaday it's best just to look for marketing phrase high sensitivity.

 

Is the SiRFstarV found in any consumer grade GPSrs yet? I haven't been keeping track.

 

switching Glonass on is said to help away multipath issues.

Is there any science behind this or is this still anecdotal? I'd love this to be true but can't think of why it would be. I suspect it just the result of adding an additional GPS constellation to the equation.

[tr_s]

Is there any science behind this or is this still anecdotal? I'd love this to be true but can't think of why it would be. I suspect it just the result of adding an additional GPS constellation to the equation.

 

Anecdotal afaik. One reason I can think of is if the systems are used separately and in parallel, and weighting from the different systems is based on signal strength/quality. If most GPS sats are blocked from direct LOS, there is at least the likelihood that a few Glonass ones are not, "canceling out" the errenous position derived from bounced GPS signals. Not a cure to the problem, but I can at least see some plausibility to the theory that it would reduce it.

 

Missed your notice about similar receiver chips. I do not know if the Sirf VI/V have made their way into consumer/prosumer grade GPS yet.

[+BAMBOOZLE]

Pay a little more and get a Garmin 62S....great under canopy with Quad antenna, large bright screen, high sensitivity receiver and more.