OFF TOPIC-GPS advice sought please

On Mon, 20 Mar 2006 15:28:04 -0600, with neither quill nor qualm, Rex B quickly quoth:

There's a good straight-line there somewhere, I'm sure.

Has anyone looked into Google Earth? You can see your property down to one meter resolution through the satellite's eyes. It's downright muckin afazing.

I took my Garmin 176 out to find the corner steaks of my property. With a clear view of the sky it will get you within 8-10' but under the trees it is only good to get you within 25' of so but the big problem was that I spent to much time looking at the GPS and not enough looking where I was going. Got the worst case of poison ivy I have ever experienced!

Garmin or Magellen with external patch antenna. The better antenna makes a huge difference because it shags more satellites at lower angles under forest canopy, which results in less geometric error. Garmin does an excellent job of dealing with an over-constrained problem, perhaps with singular-value decomposition. Whatever, it works. Magellen is probably as good, my experience is with Garmin. Minimal Garmin. I don't need or want all that fancy map crap, I just wanna know where the hell I am. I don't need or want a GPS any bigger than a pogeybait candybar.

Marvin sez: "> A friend of mine in the UK is building his own sextant and has put together a

Thanks Marvin for the great ref. to building a sextent. It was quite informative.

Bob Swinney

I don't have the PC power to run "Earth", but I've looked up our house on the sat pix in Google Map's. There is a stone wall running down the middle of our back yard. It's 2' wide max and I can see it on the Google pix!!.

So, if that's the resolution available to the public, for free(!), I'll bet the military satellites can see when my shoe lace is untied!

Bob

It's more like 1.5 GHz.

Joe Gwinn

I've used the Garmin GPS 72 (WalMart sporting goods, about $150) on my boats for about a year. Nice, basic unit.

My kids use it to measure jogging speeds and distances, so maybe you can justify it as an exercise device!

I found a Garmin Geko 101. I think they sell for $89.95. Downloaded a manual to figure out how to find the various menus. Took it on a walk, on a route I know to be about 1.2 miles. The Geko said more like 2 miles. Oh well, I didn't really expect it to be much good.

Tried it again the next day. It was spot on. ????? I then realized that the first time I didn't have a pocket on my shirt so I'd just carried it in my hand. It had measured the total distance my hand had moved, swinging back and forth like it does while walking. Second time I had it in my shirt pocket.

I don't know how well it would work under heavy tree canopy. My walking path is what you might call "residential wooded" -- some trees but I can always see some sky.

On Fri, 24 Mar 2006 10:58:44 -0600, with neither quill nor qualm, Don Foreman quickly quoth:

That's amazing accuracy, isn't it? What a trip. Your hands move 66.66% more/farther than your body during walks/hikes.

Peak vs RMS, eh? Good thing we don't measure athletic performance like vacuum cleaners or stereos or air compressors.

On Fri, 24 Mar 2006 21:25:35 -0600, with neither quill nor qualm, Richard J Kinch quickly quoth:

Close. (.5998 vs. .707)

^^^^^^^^^^^^^^^ Is that real horsepower or Searz horsepower? Let's see: 6.5hp is claimed on a 120v/20a circuit. I _don't_ think so.

I'm sure it wasn't an accurate measure, but I was still impressed that it could even respond to small motions like that.

Thanks Don for the heat sink source. The only one I found in my search was from Radio Shack made for a power diode, less than 1 inch square. Also, I needed a place to mount the power pluck. I tested with a 10 ohms, 10 watt resistor instead and I seem to have gotten the same run time before dimming. About 6 hours with a 4500 amp hour 12 volt battery. I was already stuck with the 17 dollars power puck. I will save the source if I make another light.

"Eric R Snow"

Thanks Eric; I enjoy sharing. This group is the most sharing of any group that I read. But from My experience as a metal worker. that is the nature on the field.

On Sat, 25 Mar 2006 18:02:17 -0500, with neither quill nor qualm, "Bill Cotton" quickly quoth:

I'm familiar with Ram Mounts having seen them at COMDEX years ago. They're rubber-covered steel or aluminum. Great stuff, and not too pricy.

Thanks. I'll check those out.

Good enough, eh?

- Inside every older person is a younger person wondering WTF happened. ---

That sure doesn't say much for the power puck. Even an 85% efficient switcher would deliver 5 watts for at least 9 hours from your battery. 6 hours sounds about right using a dropping resistor.

First, a correction, which you knew that I intended 4500 mAh above. I tried to send the power pluck back. But to be fair, I only tested the power pluck once on the bench. It seemed the light began to dim and it was bed time and I turned it off. I didn't want to drive the NiMH to zero. I will test the power pluck one day that I can watch it and have the alternator tester connect to it. I think that the power pluck may cut out at a low voltage. About battery life of handheld gps. The Quest is more for a car and has a internal battery, most hand held gps use two AA cells and get about 12 to 20 hours. The newest gps engine use in Garmin SX series, gets faster locks and better reception in canyon and forest, is reported to get shorter battery life. Also use of the back light shorten the run time.