"John R. Copeland" wrote in
message ...
That is correct - there's no adjustment on the encoder.
Your encoder reports density altitude [PRESSURE ALTITUDE]
to ATC.
ATC computes an altitude correction factor for their own
displays.
Some cockpit instrumentation computes the identical
correction,
allowing the pilot to know what altitude ATC is displaying.

"kevmor" wrote in message
oups.com...
There's no adjustments on the encoder? I can set the
altimeter on the
ground to the airport elevation, so I know it should be
really close
to the correct altitude, but then ATC may see my altitude
as being a
hundred feet off... The encoder never needs to be
recalibrated? It
just sees what is at the static input?

On Mar 20, 2:16 pm, "Jim Macklin"
wrote:
Not legal, you'll screw it up. Even an A&P is not
allowed
to "adjust" instruments internally. You should take it
to a
certified repair shop if it won't pass a IFR check. The
encoder is factory set at 1013.2 mb/29.92 and there are
no
field serviceable adjustments.

If the static systems is wrong, the altimeter system and
airspeed will also likely be wrong.

"kevmor" wrote in message

ups.com...
| How can you adjust an altimeter if the pressure isn't
correct in the
| window for the altitude? I started talking to my
examiner
about it on
| the checkride and he said that a lot of people adjust
it
themselves
| (not an avionics shop, etc), and he said you take the
front off (I
| think) and theres a screw to adjust it? The plane
would
be used for
| VFR only...
|
| Is there an adjustment that can be made to the encoder
as
well if it's
| off?
|