Compass in my truck - problems!

I am trying to find a usefull compass for my dashboard or windshield mounted.

I have a really cheap little suction cup model that sort of works, but is usually up to 30 degrees off.

I have two small boat types, neither will function well anywhere atop the dash nor held ANYWHERE around the windshield. One does do south and west ok.

Last night I tried a nice name brand from Academy. On the dash with the key on, it went absolutely nuts.

Any of them (except the suction cup) will work pretty well on the tranny hump or on top of my book box on the seat.

I have no good mounting options down there. Right now I have one of the smaller ones stuck to the face of the dash under my OD off button. The jury is still out on it. I know I can't see it worth a damn!

HELP!

What seems to work nearly flawlessly is a handheld sitting on my leg. Not very safe to look at!

HELP!!!! /ubbthreads/images/graemlins/help.gif /ubbthreads/images/graemlins/help.gif /ubbthreads/images/graemlins/help.gif

My first suggestion would be a GPS receiver, which computes your course based on position change and consequently is immune to the numerous problems with magnetic compasses (local magnetic/electromagnetic fields, metallic objects, etc.) Of course you have to be in motion for this to work.

That said, I've had pretty good luck with the electronic (flux-gate) compass that came with my Subaru. You can get them as stand alone devices or included in other gadgets (rear-view mirror, radar detector, thermometer, GPS receivers). They self-calibrate (typically by you driving your car in a circle once or twice after installation) to compensate for local magnetic effects and can be programmed to correct for geographic variance (the difference between true north and magnetic north which varies based on your location).
You also have the option with some of mounting the sensor in one place and the display somewhere else for optimum sensitivity and visibility. Another benefit is they are usually illuminated for easy reading at night.

Cheers,
Bob

Cheers,
Bob

{edit: OK, so Bob can type faster than I can. /ubbthreads/images/graemlins/icon3.gif)

Eeee. Well, I sure wish I could be more helpful, but all I have to offer is a way to spend LOTS of money to solve the problem. /ubbthreads/images/graemlins/smile.gif

GPS! Man, now I love my Garmin StreetPilot. That will tell you which direction you are headed, AND keep you from getting lost while you're heading that way. /ubbthreads/images/graemlins/smile.gif As long as you have a semi-unobstructed view of the sky, nothing will "interfere" with the compass feature.

Now, there are some pretty cheap digital compasses you way want to try. Never used one myself, so maybe others can chime in.

Otherwise, if it is late in the day, and the sun is in your eyes, you're heading West. /ubbthreads/images/graemlins/smile.gif

There are some electronic compasses that compensate for the car's magnetic field. See http://www.precisionnav.com for some nice units that aren't all that expensive.

I got soured on digitals after getting my Dad one that always needs to be re-caliblated.

If others chime in with actual experience.....

look for two adjustment screws on the bottom or sides.

One will be for E-W the other for N-S.

Aim your car north and adjust the N-S thing to get it to show north.

Then aim the car east and adjust the E-W so that it shows east.

Go back and check the N-S setting. If it is off, adjust for half of the error. Then do the same for E-W. That sould be fine for a car.

If you don't have the adjusting things, your are SOL.

Be sure and use a non-magnetic tool when you adjust. A medium priced marine compass would probably work as would one from a small aircraft (from an a/c salvager or you could pay big bucks for one at retail).

i bet the dash mounted stereo speakers are messing with the compass.seen this before.

It is hard to explain.

When my truck is parked, it faces pretty much SE. The compass on the dash is generally pointed NW at that time!

If I get N close, I almost never see S. If I get N & W close, i almost never see SE.

When I put the decent quality large compass up there (Minkota brand Marine) it basically just spun around.

I don't know what is so damn magnetic with my dashboard, but it irritates me something fierce!

My truck is parked facing in tonight, and lo and behold both compasses (dash top and dash face) are pointed correctly NW. When I turn on the key, both will change some.

The hanheld, whether on top of my box or on my leg seems almost impervious to anything.

On a different subject (light related believe it or not!) I got a GE Cool Blue 9004 Headlight bulb to try in my somewhat nasty looking drivers side headlight. With the cool blue bulb, that side is very near the same brightness as the other clearer light. A small victory!

Puzzling. I liked the idea of the speakers -- if you have dash mounted -- but their magnets would affect whether the ignition was on or off. Bought my fatherinlaw a $30 digital a couple of years ago and it's worked fine after it was set up.

BTW I just put Sylvania SilverStar 9004 bulbs in my truck. Real improvement. Brighter and whiter. About $20 at O'Reillys.

I have speakers in the doors only. This is decidedly NOT a listeners delight vehicle!

The dash has a pod right in front of me with gauges including a Tach. Any compass setting right on the pod is affected. Also moving down off the pod towards the center doesn't help. Holding anywhere around the windshield with the 'better' compasses offers no real help either. They are fine down on the tranny hump, or up on my book box to my immediate right.

I don't have an Antenna in the windshield. I don't have a lighted or otherwise electrified mirror.

The cheapy CHEAP suction cup 1" compass I got from Walmart will sort of work about halfway between dash and roof on the windshield. It spins around often as it isn't damped worth spit. It also is usually up to 45 degrees wrong at any given time. It WILL give a general idea which way I'm going.

I will try to get a pic or two up when our 'good' DSL 'puter gets back from the mad scientist (you know lightning and such!).

I was gonna get Silver Stars (and still might). But my drivers side headlight REALLY needs replacement. I got the Cool Blue as an experiment, and it worked for the most part! This way was less than half the price!

I'm not as bummed out as I have been. My very possible 'new' dog will be here in about 2 hours. A Min-Pin named Bart. If he's as described and pictured, and likes me, he stays.

I now have a really cool little mini dobie named Bart. He is on my lap as I type this! Little dude is athletic! Jumps up on the back of the couch from standing still. Seems to like me quite a lot!

When I came back from Easter dinner I backed in.

The dash FACE compass says SW. The windshield cheapy says SE. The tranny hump compass says SE.

The handheld when on the box says SW. When on my right leg (no keys in pocket) or outside the truck it says SE.

So SE is the truth. And neither medium sized liquid filled compass will agree to that if on or near the dash.

I guess I'll have to create a mount down on the hump (I keep gloves there now which form the place I put the compass). I will need to use a lighted compass for sure.

I'll never know why my truck won't allow a dash top to be used. It is a bummer however!

a fellow i work with rebuilding tv sets had a 70 ford pickup that would mess up purity in any set you would turn on in the bed.i had a 72 at the time and it would not do that.
maybe his was picked up with a magnetic crane at one time and magnetized it?btw the only real difference between the 70 and 72 was the grille.and this was in the days of tube tv's.

As luck would have it, neither somewhat decent compass I now own is lighted. Sigh.

The one down on the tranny hump seems perfectly happy. Just gotta get me a hunk of aluminum flat about 2-3 inches wide... and do some custom bending! And of course get a lighted compass...

Maybe time for an exorcism.

I found a digital compass at Sears for $25 that works great and is lighted. It works perfectly in a spot that regular compasses wouldn't work due to an auto-dimming mirror. I'll see if I can find the box and model# and post it.

After selling good quality compasses for years for boats, I have come not to trust the little ones in something like a vehicle with all of the metal and electrical fields what so ever. As stated above, if you can get one with some compensation adjusters, this will help. The problem I see, even with the flux gate compases which can "map" the anomolies as you swing the compass, is that you will likely not always have the same "interference field" effecting the compass. If you swing the compass for daytime, the lights, electric fan in the heater and other electronic devices might well have noticible impact on the compass. If you look at the old ships compasses, they had large iron balls on either side for adjusting and the state of magnetic interference in their proximity was probably a lot more stable than your vehicle. A GPS is great, especially if you are holding a steady enough course for the GPS to average in and report. A GPS will not tell you which direction you are pointed in, in your driveway though. /ubbthreads/images/graemlins/grin.gif

On a trivial side note, good marine compasses are sold specific to geographic zones. A compass made for the region in North America will not be accurate as is in New Zealand. I think it's a question of variation but it's been so long, it could be deviation.

[ QUOTE ]
McGizmo said:
If you look at the old ships compasses, they had large iron balls on either side for adjusting...

[/ QUOTE ]

Insert joke about telling new deck hand that they will never polish, but only paint the "navigator's balls".

[ QUOTE ]
On a trivial side note, good marine compasses are sold specific to geographic zones. A compass made for the region in North America will not be accurate as is in New Zealand. I think it's a question of variation but it's been so long, it could be deviation.

[/ QUOTE ]

I don't know specifically about marine compasses, but they do make hiking/survey compasses that are built according to the "dip" in the magnetic field for various locations (near the magnetic poles, the fields are more vertical--north up or south up, far away, they are more horizontal).

So, Brunton, for example, offers three types--Northern, Equatorial, and Southern Hemisphere models.

-Bill

Sears had a digital in a sale paper for $16.99

It says on the package that PNI made it, so I grabbed one.
It is called Wayfarer. Uses one 2032 battery.

After calibrating it, even though it doesn't agree with ANY of the others... It FEELS very close.

We shall see!

Bart (my Min-Pin) and I are learning about each other by leaps and bounds! He is a great early birthday present!!!

UPDATE: ARGH!!! Compass in my truck - problems!

Darn, Darn, Crud, DooDoo, ARGH!!!!!!!

Now I find the digital won't do right. Back away from the windshield, held about halfway up the windshield high (maybe 1.5 feet back) it seems okay.

As soon as I stick it to the windshield, no matter WHERE I've tried so far, it goes haywire. When I know damn sure I'm going mostly west (into the setting sun) it is telling me I'm going SE. I know for a fact my driveway faces SW (right at 230 degrees) and the compass says 89 degrees East.

ARGH!!!!!!!! It seems utterly hopeless now.

At least Bart is turning into a REALLY great dog! We went and got him a nice name tag at Petsmart. I started to notice how wrong the compass is on the way back.

I'm completely out of ideas now. I guess I'll go get another one of the cheapy suction cup compasses (whichever one seems to have the strongest N instinct!) and live with a generalization of my travel direction. Because the one I have is reasonably close where NO OTHER COMPASS has been EVEN close.