Leatherneck:
do you have yellow ones with black and white screens?
Yes. About 20-year old technology, but they still pull in new satellites as the system gets upgraded and can avail themselves of WAAS (wide area augmentation system) if need be. Slightly smaller than a bar of soap with a tether and no projecting antennas. Own two and they use two AA's. Fit well down in a shirt pocket. If they've been closeted for 6 months or so, it might take them a minute to come back online, but they're within 3 to 10 feet thereafter. Before retirement I had 7 or 8 of those at work where we used them to deploy and retrieve a variety of instruments in grid patterns across sizeable landscapes. With about 10 minutes of instructions, the techs were always spot on. Same for Boy Scouts and candy bars we put out in the forest. Never lost a single bar or scout.
We rarely use them for hunting given that we're about 90% public land where we hunt in Oregon, Idaho, and Wyoming. Did once have an elk tag that excluded country within our unfenced USFS boundary. With 10 minutes of work at home, I uploaded the boundary as a track with free software and hit the trail. Did take one to Alaska where we were on an alder plain with little topography looking for moose in snow and fog. Locked in camp and was quite comfortable roaming wherever for the balance of the trip.
If one truly understands how the various units work and can manipulate data with his PC, one can get way more out them than even the makers intended.
The only issue I've ever had was attempting to map an extremely narrow chasm for a low tech scout project. With only about 30% of the sky visible, the Etrex could not consistently pull in 4 satellites. Went back with a $5K survey grade Trimble, and still had the same issues.
I'd agree with many here that a compass will suffice on land where one can't range more than 8 or 10 miles in a day. Get out of sight of land or on a sandy Sahara plain with no referencing landforms, however, and one can run around for days with a compass and never find his target or even something as large as Hawaii. Columbus would surely have embraced the technology. Once accurate clocks were invented, Cook did a much better job of navigating and mapping our world. I think he was off by about 3 miles when he came back to England after 2 years at sea. Few of us have mastered celestial navigation, and even if we have, we can't attain the accuracy of our GPS units.
Nearly all GPS units use the same chips that are about the size of a dime or slightly smaller. One can buy those chips for like $20 and assemble his own GPS unit if he has electronic and programming skills. It contains the antenna and all of the software and computer power needed to interpret incoming data. The differences are mostly related to their onboard memory if one wants maps, images, extensive data storage for every satellite and position, flashy displays, lots of battery power, a variety of other useful software, or potentially communication with real time base stations or other units. That's where we step from maybe $80 up to a $10K unit where a PhD might come in handy. For my recreation needs, $80 will do it in style.
