Re: RE: Re: Garmin altitude problems

On 11/8/2024 2:23 PM, cyclintom wrote:

On Sun Aug 11 13:26:43 2024 Frank Krygowski  wrote:

On 8/10/2024 8:38 PM, Jeff Liebermann wrote:

  As I understand it, all aviation barometric altimeters are temperature
compensated.  I would think the aviation temperature compensation for
air density method is somewhat similar to a marine barometer:
<https://www.faa.gov/air_traffic/publications/atpubs/aip_html/part2_enr_section_1.8.html>
I couldn't find anything that shows how the various gears work and
where the bi-metallic temperature compensator is located (because of
numerous interruptions today).

I just opened up the wall mounted aneroid barometer here in my study, an
antique I inherited. It's an extremely simple lever mechanism, no gears
involved. The capsule pushes up or down on a long thin lever arm. The
vertical motion of the lever's end is converted to a horizontal motion
of a tall thin post, which anchors the end of the smallest roller-style
chain I've ever seen, maybe 0.050" pitch. That wraps around the needle's
pivot shaft.  Here's a photo:
https://www.flickr.com/photos/16972296@N08/53916400376/in/dateposted-public/
   (Sorry, the "tall thin post" is in shadow.)
>
The left end of the lever system is not a pivot point, but instead is a
rather wide brass stamping. I'd think that part could be made bimetallic
to provide temperature compensation.
>
>
-- - Frank Krygowski

    Remember that ALL metals expand when heated ...

Tom, why are you wasting our time and yours by exhuming threads from three months ago? And why are you then diverting the threads into rambling non sequiturs?
We don't need to be watching the dregs of your lucidity evaporate. You should keep that to yourself.
--
- Frank Krygowski