TomTom GPS unit as tractor speedometer?

[lhfarm]

I need a speedometer for my TC40DA while running my sprayer. That doesn't happen often and I'm trying to find a unit I can use on the road (in the car) and off (in my field/woods). I have friends who have TomTom units ( a One and model 720) and really like they street features/operation. Anyone using either model in the field?

Other suggestions for an on/off road device?

Thanks,

 

[MessickFarmEqu]

OBK-SL General Outback Guidance S-Lite

Outback guidance makes a GPS solution specificly for spraying applications. Its $1000, but does cool stuff that automotive GPS units will not do.

 

[bigshovel]

Garmin 60csx is an all purpose unit easy to use and lots of features. will take on road software and topo maps, very portable and economical. Will give accurate speed.

Brad

 

[Gittyup]

The only problem with GPS is that most consumer units update only once per second. I'm not sure if that would be often enough. GPS receivers take a few minutes to acquire accurate location and speed on power up, and you'll have to allow for that. You should also check the accuracy at low speeds.

A simple speedometer might be a cheaper solution.

 

[MReeb]

The only problem with GPS is that most consumer units update only once per second. I'm not sure if that would be often enough. GPS receivers take a few minutes to acquire accurate location and speed on power up, and you'll have to allow for that. You should also check the accuracy at low speeds.

A simple speedometer might be a cheaper solution.

I found the same problem back when GPS first came out. I was using a Garmin 45 and it didn't have differential correction. With slower speeds my position and speed would jump all over the place. I ended up getting a unit called Calc-An-Acre. I'm thinking it was like $300 - $350.00 when I bought it. It uses a magnetic pickup and if you enter a width it'll tell you acres covered, etc...

 

[RobJ]

I found the same problem back when GPS first came out. I was using a Garmin 45 and it didn't have differential correction. With slower speeds my position and speed would jump all over the place. I ended up getting a unit called Calc-An-Acre. I'm thinking it was like $300 - $350.00 when I bought it. It uses a magnetic pickup and if you enter a width it'll tell you acres covered, etc...

If this was years ago...back in the 90's then this problem should be fixed. Clinton took out the GPS error codes in the late 90's.

If you move at a constant speed for a few seconds they are very accurate. We just bought a Garmin Nuvi 200 for my MIL. Very accurate and the touch screens are real nice. this is the cheapeat model, the screen was a little small but everything else was simple to use. The bigger ones might have a bigger screen but the cost can go up in a hurry. This one also has a picture viewer in it (SD card). It was slow and not that great.

I think on some of the handhelds you can set the refresh rate...

Rob

 

[Treemonkey1000]

Depending on how accurate you want to be the handheld kinds with WAAS should be plenty accurate. I have the Garmin 60CSX for hiking. I could move that thing one foot and it would show that fairly accurate. Along with speed that I am walking or even driving on the freeway. You can download Topo maps onto it.

 

[MessickFarmEqu]

WAAS is much more accurate than GPS.

 

[TomOfTarsus]

Over at Groundspeak Forums Redirect (as well as others) you can find a wealth of discussion on both car and hand-held GPS equipmement, and probably numerous discussion of WAAS vs. "regular" GPS. I occasionaly post over there under the same user name as here.

For me, I'll be interested when they get the new civilian L2C satellites & signals going. It won't be as much fun for geocachers (who need a little inaccuracy to make the search fun), but for us accuracy freaks, getting within a foot or so will be something!

 

[Toolguy]

Just for fun, I put my Garmin GPS on my tractor while I mowed the lawn. When I was done the trackback feature showed an exact pattern of where I traveled. I also found that to mow my approx. 1.5 acre lawn with a 60" MMM I traveled almost five miles. I also use that GPS on my boat. In addition to knowing the present speed it also tells you how far you have traveled. Not many boat speedometers have odometers. too. I have also used it in my trucks to check the speedo. Most vehicle speedos are off a little bit. Interesting toy/tool.

 

[lhfarm]

Just for fun, I put my Garmin GPS on my tractor while I mowed the lawn. When I was done the trackback feature showed an exact pattern of where I traveled. I also found that to mow my approx. 1.5 acre lawn with a 60" MMM I traveled almost five miles. I also use that GPS on my boat. In addition to knowing the present speed it also tells you how far you have traveled. Not many boat speedometers have odometers. too. I have also used it in my trucks to check the speedo. Most vehicle speedos are off a little bit. Interesting toy/tool.

Which model were you using? So it would show your speed as you were mowing? That is what I need.

I spray only once a year and I'd like to use the unit in the car the rest of time. I may end up with two units, but would prefer to spend more money on a unit my wife can use.

 

[GinNB]

I don't have a TomTom but use GPS all the time at work (I'm a farmer). Any kind of consumer gps that shows the speed down to a tenth of a mph will make a good spraying speedometer. If the TomTom will show you that level of accuracy and give you a toy for travelling in the car then I'd say go for it. I use a Garmin handheld but it's not as good at the street navigation end of things (no voice directions, no touchscreen and the screen's too small). You'll need a foamer or some other way to flag where you've sprayed though.

Consumer GPS units are almost useless for navigation (certainly row-to-row navigation). Been there tried that. Static accuracy standing in the open is one thing, but moving accuracy dealing with reflections from trees, trucks, buildings, hills, your tractor bucket etc is a totally different kettle of fish. Even things like the Outback Lite will most likely give you strips in your coverage, and that's if you can guide the tractor as accurately as the unit will show you to. Something like EZSteer is needed to get the most out of GPS guidance except under the easiest of conditions. Foamers are much better, and I find them better than even my Trimble EZGuide Plus for many things. I use whatever's better in each situation, but then I spray commercially hundreds of hours a year.

 

[nbennett]

I have a TomTom and think that it would work great for giving even low speed readings. My concern would be protecting it from vibrations because they don't seem to be too tough if abused. Some of the car navigators are not recommended for motorcycles for the same reasons?

 

[Mickey_Fx]

One unit you might give consideration is the Magellan Crossover. It has 3 modes of operation, highway, marine, & off-road.

As for WAAS and increased accuracy, I don't think it buys the avg user anything. Believe it is intended for aircraft nav and the sat that provides the data for it is located low in the southern sky. On my Nuvi I can turn WAAS on/off and I don't see any difference. Out in the open, accuracy is reported between 15' and 19' regularly.

 

[Hookblock]

I have a lowrance Ifinder h2o, I use it with my truck,motorcycle,boat,snowmobile, and in the woods, new use tractor I like it, it works great,water proof, expandable memory, I think between 200-300$. Down side is battery life.

 

[ihookem]

I have a Garmen Etrex. It might not be what you want but as for a spedometer it's very accurate. My spedo went out on my pickup and they want 463 dollars to fix it. It keeps mileage too and is exactly 3.3 % of of my odometer.

 

[Steve in IL]

Barry - I put a bike speedometer on my TC21D. It has a magnetic pick up on one rear tire. You'll need to find one that the wheel diameter can be programmed to something close to what is on your tractor. $10 or so.

 

[PILOON]

Well one of my new toys is a Garmin 350.

For the heck of it I mounted it in my Mitsubishi MT180D since I always wanted to confirm that it was faster than walking, LOL !

I blow snow from my 3 properties, hence move around a bit.

Simply stuck it to the windshield with the suction cup mount and it works great.

Suprised the heck out of me as I had forgotten that I was programed for 'home' and it bleeped to tell me that I'd arrived!

And, oh yeah, I do a whopping 7.5 mph top speed flat out!

For your purposes I did find it very sensitive to throttle settings with very reasonable response time.

 

[mjncad]

Barry - I put a bike speedometer on my TC21D. It has a magnetic pick up on one rear tire. You'll need to find one that the wheel diameter can be programmed to something close to what is on your tractor. $10 or so.

I like this idea as it is simple and cheap. I still use a foldable 2D navigation system in my car and truck (a.k.a. a map).

 

[GinNB]

Barry - I put a bike speedometer on my TC21D. It has a magnetic pick up on one rear tire. You'll need to find one that the wheel diameter can be programmed to something close to what is on your tractor. $10 or so.

Been there, done that on my ATV sprayer. Works fine with a few weak points. Precision on the ones I've seen and used is .5mph (or .5 km/h) at lower speeds. I just picked a spraying speed (5.5 km/h) and sped up until it just started ticking over on that value so that I could repeat it. The wire was vulnerable to sticks and branches, but wireless ones are available. having the correct wheel diameter available in the bike computer is optional, too. Just don't use the speed it gives to calibrate the sprayer if you know what I mean. Use it like a tach when you don't know what gear your tractor is in (for repeatability).