New Monroy ATD-300 Traffic Watch

Hi Thierry:

As you can tell, we're all skeptical about all these new boxes and are waiting
for someone else to be the guinea pig. So tell you what - I would be happy to
review a ProXalert for you and this newsgroup. We fly about 200 hours a year
in a Glasair based in Phoenix, AZ, with a flight school on the airport (lots of
traffic) and Class B above (lots of air transports). There can easily be 15 to
20 aircraft within 12 miles of the airport, and there's an ADS-B test going on
up north of here. We have DME along with the transponder to give your unit a
good workout.

I've written a few articles for KITPLANES and have posted a few unsolicited
reviews in these newsgroups. (Do a GOOGLE search for "Review of Plasma II
Ignition," open the search to show the "omitted results included," and you'll
see Jim Weir says, "I don't know about the rest of ye's, but this is about the
best piece of writing I've seen in this NG in the last 4 years.") As I've
posted here before, we've been flying with an ATD-200 for about two years now
and have a lot of experience with that unit.

You arrange a month's loan, I'll sign the papers, you overnight it to us, and
if it's as good as you say, I'll let everyone know. (The only thing I won't be
able to test at this time of year is how well it holds up in 120 degree heat.)

Mike Palmer
Excellence in Ergonomics


In conclusion for a little more money you can get a professionnel
grade unit at still a very competitive price compared to other professionnal
devices.

Monroy ATD-300


I recently purchased the traffic scope vrx device and have found it to
be very accurate in pinpointing surrounding traffic. I just got the
newest software version and it gives me altitude within 5000 feet and
they also threw in an altitude alerting feature which I can use to
check my drift (especially on long IFR XC which I am often
complacent!!!) I noticed a couple other companies claiming to do the
same, but there are differences. I thought I would give my 2 cents on
what I have learned over the past months.

First the ATD-300. It is small, but I don't see any way they can
accurately determine "my" altitude since it is only getting an
altitude from my own transponder (if it is talking). I fly IFR many
time and I know that the codes issued to me are often codes that can
be altitude codes as well. Oops! Maybe they forgot this detail? Maybe
not! That being said, I talked to surecheck about this they said to
try an experiment in - why using just a transponder does not work,
they had me select a mode setting that made the traffic scope only
listen to transponders. They said when you fly around metal buildings
the code will get corrupted because of signal "multipath" sure
enough, it did. It seems as though the Monroy company saw their
future competition and tried to throw together last minute a device to
compete with the new market. I don't know how well they will do when
they can't for sure know what altitude you are flying. The features
are brief, and again seem to be made from an older version.. However
the voltage readout is nice. You will have little ability to narrow
down the airspace you view since its mode functions are much less than
the other 2 mentioned models.

I also looked at the Prox-Alert device. While this does seem to use
some sort of altitude backup, the size is much larger, and it like the
ATD-300 is dependant on the aircraft for power. I think this is where
the sure check device has them beat, since you can add 4 "AA"
batteries directly to the traffic scope and just fly. The Prox-Alert
gives squawk codes, but to be honest this does not seem like a major
benefit other than I know he is IFR or VFR but hitting either id
deadly is it not? From what I can tell this product was developed in
France, and this may limit their ability here greatly since traffic
conditions here in the US are much more intense. I read through their
product brief and discovered that they anticipate this device being
used more in a rural setting than that of say Chicago O'Hare. The
Prox-Alert has an odd shape to it. It is "L" shaped to mold over a
dash (if you have this type of Dash) to accomodate the display. This
may help stabelize the unit in takeoff or landing conditions which is
nice. In talking to them they did say this is their first product, so
some reviews would be good from independant sources before purchasing.

Overall My opinion still rests with the sure check trafficscope mainly
because I have used it, it has proven to work well, can accept
batteries directly, and is the most reasonably priced for features.
It is extremely small and fits on my dash well. Their customer service
is top notch, and all of my questions where answered by someone who
obviously knew a lot about the device. I think they have been around a
while and their experience obviously went into the design of this
device. In talking to them the one thing I really want (Bearing to
the traffic) is still out of reach for cockpit TCAS

I will report back on my experience as time progresses as well.
Please email me as I enjoy discussing this topic as you can tell (and
with my former students)! I think more pilots should wake up and
realize our airspace is not as un-occupied as it once was. Hell, I
remember when I was the only stick around for 1,000 miles in fact they
almost shot me down 3 days after Peral Harbor!!

BHelman,

They said when you fly around metal buildings


Huh? Pray, tell - when would you be doing that?

Your own transponder in mode C (or S) sends out an altitude signal
derived from a pressure sensor in the plane. As I understand it, the
Monroy receives that and uses it as your own altitude. The Surecheck
apparently has its own sensor built in. From your post, I fail to see
any difference of relevance. But maybe someone could explain?

--
Thomas Borchert (EDDH)

Thomas Borchert wrote in message ...
BHelman,

They said when you fly around metal buildings


Huh? Pray, tell - when would you be doing that?

Your own transponder in mode C (or S) sends out an altitude signal
derived from a pressure sensor in the plane. As I understand it, the
Monroy receives that and uses it as your own altitude. The Surecheck
apparently has its own sensor built in. From your post, I fail to see
any difference of relevance. But maybe someone could explain?

The traffic scope reads the transponder signals from what I can gather
by reading their manual. The "conflict" light lets you know when there
is a "miscommunication", transponder failure, or you drop out of radar
contact, and then resorts to the altimeter inside. In talking to one
of their reps at Oshkosh, the problem they discovered is that when you
fly around buildings or mountains apparently the signal from your
transponder echo mess up the altitude code, so they have the built in
altimeter there to check that the altitude traffic scope uses is the
right one, which I think is what they said they got their patent on.
At their suggestion I tried an experiment with this using only
transponder altitude, which shuts of their altimeter with a small
switch on the bottom, and you definitely notice a sudden change in
altitude to some random level when you fly near a mountain or certain
buildings (mainly metalic looking). Also you notice on the ground, on
an approach or have a parellel approach it would swing between my
altitude and the other guys because it can't tell who's transponder is
sending which altitude. What happens if you are just below radar
contact using the atd-330? At that point I would think all they could
do is guess your altitude and hope it is right!?!? I think that device
sounds like a good idea, but they might not have thought it all the
way through if they are soley relying on the transponder for their
altitude, but if it does have some sort of altitude sensor this would
be a whole different story, but then I guess they would enfringe on
the traffic scope patents. Oh well, I am sure todays minds can figure
something out. They usually do!

I do find this facinating, mainly because I have had so many
"feather-dustings" throughout my life that I think it is good that
people are finally taking this more seriously.

Hope this helps.