All you have to do is look at their user manuals on any of these
devices to see the ATD300 has hardly any features. I am just reading
through, side by side, the features.

http://perso.wanadoo.fr/proxalert/download/ProXalert%20R5%20-%20Product%20Brief%20(Nov%202003).PDF
http://www.monroyaero.com/ATD300Manual.pdf
http://surecheck.net/five/pdf/VRX_1-0-1_Full.pdf



These are the deficiencies I noticed from comparing the different
models. The ATD does have a bus voltage monitoring, but when you look
at all of the other factors, I think it comes up short.




The ATD does not have an altimeter, which leaves it to listen to any
nearby transponder for a reference altitude. Like I showed before
this could be problematic if you start squawking any of those codes.

The ATD requires you to have an aircraft with a working transponder
and be flying in adequate radar coverage at all times.

The ATD will not show any altitude outside of a 1000' window

The ATD does not take batteries

The ATD has a resolution of 1.0 NM increments only. Saying an aircraft
is less than 1 NM is poor resolution around an airport, where as the
others go from 1.0 down to 0.1 NM

The ATD does not have any volume control for in flight use

The ATD does not have any way to show how many other threats are
around you.

The ATD has no visual indication of alerting you

The ATD does not have any dataport for upgrading or interfacing

The ATD does not have an independent mode selection system for range
or altitude

The ATD audio interface has no mixing or mono-stereo selection

The ATD has no altitude drift alarm

The ATD has no selection of flight status, like ground, or flight

Check them out, they all have manuals online.




Thomas Borchert wrote in message ...
Loran,

If you look at the ATD
sure it is low priced, but it also doesn't have near the features or
resolution as the other devices.


Care to explain?