Altimeter for the MH

My old Garmin GPS calculates height above MSL the same way it calculates geographical position (3D geometry).

When locked on to 10 or more satellites, it is accurate to within one foot for altitude and within 6 inches for geographical position.

I don't know if there is a calibration for it, but my Garmin GPS is not even remotely accurate in telling altitude. Recently we were at the highest point in Florida (345' for those that want to know)(stop laughing those of you with real mountains or even big hills) and out of curiosity, I checked in on the Garmin and it said 460'. It stayed steady on that reading.

My Garmin Nuvi 2555 can be configured to constantly display the altitude with the primary map display.

Remember that if it's an altimeter that works on barometric pressure rather than GPS location, it'll be sensitive to changes in pressure due to minor or major weather-related pressure changes. That can lead to some pretty major inaccuracy if you don't keep it calibrated. My decade-old Garmin hiking GPS works that way (I asked a Garmin tech).

Jim, "'Past tense' means you used to be nervous."

Mandalay Parr wrote:
iPhone app does it all Some free, some $4.

That might be the best way to go, although I would prefer something on the dash that I could glance at, rather than having my wife bring it up on her iPhone5. My antique Samsung flip-phone with pull-up antenna might be inadequte... although my reception can often be better?

iPhone5 Altimeter App

iPhone app does it all Some free, some $4.

There is a 24 step process for adding the altimeter function to my TomTom. It is only offered by a third party provider (not supported by TomTom), but it is freeware (donations appreciated). I have found that my TomTom is sensitive to upgrades so I am a bit leery about adding it?

GPS or smartphone will give you that info.

Pangaea Ron wrote:
I like to have some idea of elevation as I am driving and would like to get a dashboard mounted altimeter.

The Sun 205F seems to get good reviews, but it seems small?

Sun 205F

A compass might also be nice that would be more visible than the one on my TomTom GPS.

Any suggestions?

I have one very similar on my dash, only I find it hard to see the numbers on it