jgf310

so, you are suggesting that "fixed elevation mode" makes the unit report the GPS elevation, rather than the barometric elevation. that would be fine, if i could be sure that the reported barometric pressure was still being reduced to sea-level using the elevation i input when it asked if i knew my elevation in the calibration... but because every time i go back and look at that calibration value, it has changed..., i am suspicious that it is not doing so. i suppose that it _is_ possible that the value being displayed when i check the calibration is that GPS elevation, but it is still using the value i entered for the calculation...

I currently own an HCX, an Etrex 30, and an Oregon 400C I mostly use them for sailing, and would like to monitor barometric pressure. I have been owned Garmin handhelds with a barometer/altimeter for probably 10 years, and have never had one that worked the way I think it should. I always see the same problem; when i set it to "Fixed Elevation Mode"..., The elevation still changes..., so I don't trust the barometer. Obviously, when I am sailing, my elevation is fixed - nearly always at sea level... So, in setup > altimeter, I set auto calibration to "off", and I set Barometer Mode to "Fixed Elevation" Then, I calibrate the altimeter, with my known elevation. On the altimeter page, I select "Plot Barometer". I set a data box to display "Barometer", and the other one to "Elevation"..., thinking that the Elevation will remain fixed - but it doesn't... Not only does the displayed elevation not remain constant..., if I go back to the calibration page, where I have entered my known elevation, that has changed too!!! It's changing my calibration entry! after a while the elevation change, in "Fixed Elevation Mode", can be a few hundred feet... Of course, I can no longer trust the barometric pressure... I have called Garmin a few times, but I have never even gotten to speak with anyone who really understands the problem... It seems to me that it is a firmware issue..., in fixed elevation mode, the unit needs to be told not to interpret ambient pressure changes as elevation changes. What am I missing?

I have an Etrex 30, and there is not a Glonass-only mode.

No, the G2 charts are the Garmin brand vector marine charts. I spoke with a customer service guy yesterday, and he said he was going to make some sort of notification to the tech people, to see if perhaps it is a software issue, that might be fixed by improving the code. The reason I was interested in hearing about performance with garmin vector topo maps, is that I don't believe that they have changed much recently, while the G2 charts are (supposedly) a big change from the older Bluecharts which i used on my Vista HCX. I am wondering if perhaps the G2 charts have much bigger file sizes than the Bluecharts, and if that is why they render so slowly. One thing I learned, was that apparently I can use Mapsource to load older bluecharts on to the Etrex 30 - that would provide an interesting test of the rendering ability. I had been under the impression that Mapsource could not be used with these newer units. The problem is that I don't have any unlock codes left on my Bluecharts. I do have the old topo maps, which had no limit on the number of units they could be installed to, so i plan to try to use Mapsource to put them on my Etrex 30.

has anyone tried the garmin topo maps in one of the new etrex units yet? how do they render?

I just received my new Etrex 30. I have been a very happy user of the Etrex Vista HCX, for many years. I have been using the Vista with Bluecharts, and it works very well. Along with my new Etrex 30, I purchased the G2 marine charts. The Etrex 30 is so slow to draw the charts, that I will probably return everything, and just keep using the Vista. Zooming (in, or out), and panning the charts is painfully slow on the Etrex 30. The Vista HCX with bluecharts is quite good in this respect - absolutely no lag in drawing the charts, either while zooming, or panning. I'm not sure if the processor is slower, or the chart files are bigger, or perhaps it's some other issue... The Bluecharts were loaded on the Vista via Mapsource, from a CD, whereas the G2 charts are only available on micro-SD. I wouldn't have thought this would be a problem though. Anyway, the Etrex 30 seems a real step backward in this regard.