On 4/7/2021 10:35 AM, Tom Kunich wrote:


The one problem with barometric altimeters is there can be two sources of errors: 1. When a front moves through the barometric pressure changes and you can show errors. 2. As you point out the sampling rate is important for accuracy. Usually not for absolute altitude for which they are surprisingly accurate (Over the years I've had perhaps a dozen different barometric pressure altimeters and they are all in very close agreement.) but the sampling rate really does screw up the rate-of-climb or grade calculations.

I'm not much into riding data. But long ago, I was given a Nike watch
(Lance Armstrong model) with a barometric altimeter and electronic
compass. I had some fun with it, but it lost its mind after a few years.
The altimeter began acting as if I were riding upward in a hot air
balloon. Several attempts at disassembly yielded no fix. It now sits in
my workshop hoping for a miracle.

--
- Frank Krygowski