Jump to content

How To Avoid Losing Sat Signal?


osprey46

Recommended Posts

Other more "modern" GPSr units have shown to be much more effective under treecover that older models like the non-color eTrex's.

 

A newer GPS is still no guarantee of solid aquisition, but it has been demonstrated often to be the case. Heavy treecover performance has been an Etrex archiles heel.

Link to comment

Tall dense pine forests have left my poor little Foretrex 201 whimpering on a number of occasions. Usually it's pretty decent, but there's something about those big ol' conifers. Various things I've done to compensate:

 

Sometimes having a topo map (like a printout from TopoZone) can help, particularly if there's enough features in the area to get you close - sometimes you can see that the cache is at the top of a hill, or near a sharp bend in a stream, a little bit northeast of where two fire roads cross, that kind of thing. Won't put you right on top of the cache, but it might get you close enough that you can spot a distinctive/traditional hide spot with a little bit of wandering.

 

On a similar train of thought, if the cache is in a state park or similar area, try a quick web search and see if you can locate a trail map for the area. These often show more trails than topo maps do, and by comparing where the little red cross on the TopoZone map is to the park's trail map, you might be able to get a much better idea of where you're headed than you would from the topo map alone. 10-15 minutes of mousing around the net before you head out can save a lot of time/frustration in the field.

 

Keep an eye out for fields or hilltops along the way. Even if you have to go a little bit out of your way along a side trail, or head past the cache and double back afterwards, it might be worth the side trip just to get into a more open area and re-establish your range/bearings.

 

Sometimes just taking a break and sitting still for a little while can help. The positions of the satellites are constantly changing - kick back, have a snack, see if one or two more satellites get high enough that you can pick them up and get a fix. Of course, that can work the other way - you might find that the geometry gets even worse as time goes on. But if you're stuck with no lock at all, give it a shot - things can't really get worse in that case, right?

 

Team up with a caching buddy who has a different make and/or model GPSr. My local caching friend, my dad, and my bro all have different GPSrs than I do. When I go out with any of them, it's not *that* unusual for one of us to lose lock for a little bit while another person's GPSr keeps on ticking. So we just switch who's leading based on who has a usable signal. If nobody has a lock, well, at least we're all lost together!

 

Worst comes to worst - no topos, no trail maps, no signal, no cache - at least try to enjoy the hike. :yikes:

Link to comment

One of the few really practical uses in geocaching I've found for satellite prediction programs such as those from Leica or Trimble is to find the "sweet spot" in the day for forest navigation. When you set the cutoff angle to 30° and look at the GDOP graph for the day there will probably be just a couple of half hour to one hour windows of low GDOP when you have a good chance of getting enough satellites for a reasonable fix. I've used this technique to good effect a couple times here in the Northwest where the woods consist of very tall, thick needle bearing trees, where signal penetration is pretty good at high angles but there's just too much wood in the way at lower angles. I'm not sure how much it can help in a deciduous forest covererd in wide water-rich leaves.

Link to comment

Walk to an area that has the least tree cover and hold the GPS as high as possible. If it has a patch antenna, hold it as horizontal as possible. It helps a lot to stay in one place and then use a compass to shoot a bearing to the cache. Sometimes moving just a few feet away can make a big difference in reception, so watch the sat page on the GPS and try a few different spots until you get the best reception.

Link to comment

I agree with Alan2 ..... set it down and walk away for a minute. Place it for best antenna reception (flat or upright depending on unit). Often when getting close I set the GPS unit down and start looking .... then go back to it for an update. Remember your unit does get signals thru a glass windshield!

 

Otherwise: .... Agent Orange defoliant? CHAINSAW?, Helium baloons with GPS on tether? Long extension pole and duct tape?

 

Learning some orienteering skills with a good topo chart of the area will definitly help.

 

<_< ImpalaBob

Link to comment

1. Turn your GPS on well before entering the woods. If it knows where the sats are it can pick them up quickly again if it loses them.

 

2. An eTrex must be held flat, face up to to the sky for best reception. If you clip it to your belt, hang it from the laynard around your neck, put it in your pocket or hold it in your hand dangling at your side, you may lose reception. You should hold it kind of like a waiter holding a tray of beer.

 

For long hikes, get the neoprene case and clip it to the top of your pack's shoulder strap so it sits face up to the sky. I have used a Vista and a Legend under heavy tree cover and I rarely lose my sat lock as long as its held in optimum position.

Link to comment

I don't want to start round of brand warfare, but with my SporTrack Pro I have never been signaled that lock was lost, even in the most dense forest areas. It may wander in heavy tree cover and either take a long time to settle out or may never settle completely, but it never loses signal. The reason may be something about the Houston area or it may be something about the SporTrak.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...