"Ron Rosenfeld" wrote in message =
...
On Tue, 26 Oct 2004 03:37:16 GMT, "John R. Copeland"
wrote:
=20
Now, though, non-precision LNAV approaches with defined vertical paths =
will
display vertical guidance only on the new NAV display page of the =
CNX-80,
but the external VDI instrument will not display that same vertical =
guidance.
In LNAV, my glideslope flag is retracted, but the glideslope pointer =
is driven
beyond the end of the scale, hiding it from view throughout the =
approach.
=20
That's unfortunate. But I would think it would be more logical to =
also
flag the glideslope.
=20
--ron

I was about to speculate that the glideslope flag might get retracted by =
the
flight director, because it receives a strong signal to overdrive the =
VDI pointer.
But then I checked the CNX-80 Installation Manual, and I found that
the I/O Expansion Connector P5, pins 52 and 55, are the Aux VDI +Valid,
and the Aux VDI -Valid (the current-return path), respectively.
So the CNX-80 is designed to control the external VDI flag,
and I'm assuming that my flight director is wired accordingly.

I, too, was surprised by the retracted flag with denied aux-VDI =
guidance.
But it's no big deal. I could see it as a reminder to watch the NAV =
page.
Things like these are why we don't learn our equipment from books alone.
We must fly to really learn.
---JRC---