small altimeter needed
Martyn Thomas
with limited room? An altimeter with the capability to drive a small display
from a remotely-mounted main unit would do, I guess.
--
These are personal opinions only
Martyn Thomas, Praxis plc, 20 Manvers Street, Bath BA1 1PX UK.
Tel: +44-225-444700. Email: m...@praxis.co.uk Fax: +44-225-465205
Andrew Boyd
>Where can I get a small altimeter, to act as a backup instrument in a panel
>with limited room? An altimeter with the capability to drive a small display
>from a remotely-mounted main unit would do, I guess.
well, I suppose you could just buy one of those relatively inexpensive
"blind" encoders that you plug into your transponder to get mode C.
I think ACK sells one for under US$200. If you can figure out the
format of the RS-232 output, you'll be set. Except for a couple
small problems:
1) encoders typically quantize their output to 100 ft levels.
You won't get a heckuva lot of precision. eg if you are at
2950 feet ASL, you might get 2900, you might get 3000. It might
even frantically flip between the two (though I hope not).
2) encoders output altitude wrt pressure altitude. Think of
always dialling in 29.92 in the little window, and not being
able to change it, which is a bit of a drag. Your microcontroller
(ie the catcher and displayer of the RS-232 encoder output) would
need to allow the user to input the current altimeter setting,
and fudge accordingly.
This would be esp required for you folks in the UK who do that
weird biz where you always dial in a value to make ground level
0 ASL (QNH, QPH, I always forget that stuff).
----
#include <std.disclaimer>
Jeffrey Dunkle
>with limited room? An altimeter with the capability to drive a small display
>from a remotely-mounted main unit would do, I guess.
Depending on what you want....you may want to check with the skydiving
supply houses. The vendors serving those guys have developed some
pretty slick stuff, both solid state and aneroid based, some with
digital displays. With a little ingenuity you could probably get what
you're after.
Jeff Dunkle
Jeffrey Dunkle
>with limited room? An altimeter with the capability to drive a small display
>from a remotely-mounted main unit would do, I guess.
Depending on what you want....you may want to check with the skydiving
Kyler Laird
with an "easy to build" (their wording) digital altimeter. By building
it yourself, you'd gain some control...t'would be nice for when you add
a computer with a HUD...
--kyler
David Doshay
hanggliding. Apparently there are many to choose from. Go to a
hangglider store. We flew in my C-172 with it, and whenever we looked
at it it was very close to my panel altimiter. It had far less lag
than the one in the plane.
David dos...@soma.arc.nasa.gov
The thought police insist I tell you:
my thoughts, not NASA's
Rodger Reinhart
There is a new wrist watch altimeter on the market by Avocet (Palo Alto CA)
that measures altitude in 10 foot increments and various vertical rate and
total climb functions. It will retail for $100 and has just started shipping to
retailers. I helped develop this product and have been using it in my plane for
over a year. The altitude reading is temperature compensated and the buttons
and digits are larger that a standard wrist watch.
Best Regards
Rodger Reinhart rein...@netcom.com
408-292-8066
alex france
>well, I suppose you could just buy one of those relatively inexpensive
>"blind" encoders that you plug into your transponder to get mode C.
>I think ACK sells one for under US$200. If you can figure out the
>format of the RS-232 output, you'll be set. Except for a couple
>small problems:
Do blind encoders really put out RS-232? I would have thought it was
something more native like the serialised bit code for the
transponder message being clocked from the transponder? Or even
just parallel BCD digits? Anyone know?
> This would be esp required for you folks in the UK who do that
> weird biz where you always dial in a value to make ground level
> 0 ASL (QNH, QPH, I always forget that stuff).
That's QNH for altitude (above mean sea level) and QFE for height
above airfield. We also have this annoying habit of doing it in
millibars too (er, sorry, hectopascals to be politically correct).
It feels kinda comforting to land with zero on the altimeter. I mean,
otherwise you must still be in the air, mustn't you :-)
Alex.
# Alex France, Crosfield Electronics, | Phone: +44 442 230000 xt.3541 #
# Hemel Hempstead, HP2 7RH, England. | Email: a...@crosfield.co.uk #
# AA5A, G-BEZI - more of a 'buzzin' than a 'hummin' Grumman. #