Air traffic detection question

Has anyone flown with any of these new "portable tcas" devices? I
recently got a Monroy ATD-300, which is the lowest price, that gives
range and altitude, but have been very disappointed in the
performance. My experience is that the altitude and range of aircraft
it is reporting are constantly changing drastically.

FISHnFLY wrote:

Has anyone flown with any of these new "portable tcas" devices? I
recently got a Monroy ATD-300, which is the lowest price, that gives
range and altitude, but have been very disappointed in the
performance. My experience is that the altitude and range of aircraft
it is reporting are constantly changing drastically.

Thats sad news, I've been interested in the purchase of that model,
mainly because of its "best deal" pricing as well...

Indeed sad. I've been interested in an extra set of "eyes" ever since what
initially appeared to be a bird turned into a mooney faster than you can say
Ovation Dx. I can't tell you how many times I've watched planes fly by me
without a peep from flight following.

Anyone had experience with the SureCheck RX series transponder detectors?

I guess I'll have to just buck up and get a mode-s transponder w/MFD.


-Brian


"Darrel Toepfer" wrote in message
.. .
FISHnFLY wrote:

Has anyone flown with any of these new "portable tcas" devices? I
recently got a Monroy ATD-300, which is the lowest price, that gives
range and altitude, but have been very disappointed in the
performance. My experience is that the altitude and range of aircraft
it is reporting are constantly changing drastically.

Thats sad news, I've been interested in the purchase of that model,
mainly because of its "best deal" pricing as well...

I have the vrx and have been very satisfied so far. The vrx has it's
own altimeter to back up my transponder's altitude, which probably
makes all the difference in accuracy. The traffic it reports is
usually right on the mark with what ATC reports, and has many times
pointed out aircraft I can see and vrx can see, but for some reason
ATC can not. It cost more obviously, but probably because it has the
technology to do the job right IMO. I think it is a much more
professional product overall in terms of accuracy and features.




"Brian Sponcil" wrote in message ...
Indeed sad. I've been interested in an extra set of "eyes" ever since what
initially appeared to be a bird turned into a mooney faster than you can say
Ovation Dx. I can't tell you how many times I've watched planes fly by me
without a peep from flight following.

Anyone had experience with the SureCheck RX series transponder detectors?

I guess I'll have to just buck up and get a mode-s transponder w/MFD.


-Brian


"Darrel Toepfer" wrote in message
.. .
FISHnFLY wrote:

Has anyone flown with any of these new "portable tcas" devices? I
recently got a Monroy ATD-300, which is the lowest price, that gives
range and altitude, but have been very disappointed in the
performance. My experience is that the altitude and range of aircraft
it is reporting are constantly changing drastically.

Thats sad news, I've been interested in the purchase of that model,
mainly because of its "best deal" pricing as well...

(FISHnFLY) wrote in
om:

Has anyone flown with any of these new "portable tcas" devices? I
recently got a Monroy ATD-300, which is the lowest price, that gives
range and altitude, but have been very disappointed in the
performance. My experience is that the altitude and range of aircraft
it is reporting are constantly changing drastically.

I haven't had a chance yet to put an ATD-300 through it's paces, nor to
compare it to the latest new crop that have come out in the last few
months. I do have an ATD-200 in my plane and find it somewhere between
useful and toy. Toy, because it probably only identifies about 30% of
the traffic in a useful fashion (has a habit of not lighting up until
the traffic has passed G). Useful, because it sometimes does alert me
to look for traffic out in the boonies, when there hasn't been another
aircraft within 100 nm for the last 2 hours (hard to keep a good scan
going under those conditions). A large percentage of the time it gives
false alarms.

None of these are going to give you anything more than a very loose idea
of range. Any appearance of good range information is a lie -- a big
smoothing algorithm that makes it look like good data, but still may be
grossly inaccurate.

The older units did NOT do a real decode on altitude and hence might
trigger on a jet 30,000 feet above you, and fail to detect a '172 flying
200 feet below. The newer ones are supposed to pick up the transponder
altitude, but probably have trouble keeping it matched to the
appropriate target. [I develop algorithms for the military to track
airborne threat targets and it can get complicated.] Does it vary the
altitude substantially when you are pretty sure there is only one threat
nearby?



-----------------------------------------------
James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
-----------------------------------------------

James M. Knox wrote:

I haven't had a chance yet to put an ATD-300 through it's paces, nor to
compare it to the latest new crop that have come out in the last few
months. I do have an ATD-200 in my plane and find it somewhere between
useful and toy. Toy, because it probably only identifies about 30% of
the traffic in a useful fashion (has a habit of not lighting up until
the traffic has passed G). Useful, because it sometimes does alert me
to look for traffic out in the boonies, when there hasn't been another
aircraft within 100 nm for the last 2 hours (hard to keep a good scan
going under those conditions). A large percentage of the time it gives
false alarms.

Are you using the included antenna or an external one?

I like the fact that the new model allows you to check your own
equipments ouputted signals...

None of these are going to give you anything more than a very loose idea
of range. Any appearance of good range information is a lie -- a big
smoothing algorithm that makes it look like good data, but still may be
grossly inaccurate.

The older units did NOT do a real decode on altitude and hence might
trigger on a jet 30,000 feet above you, and fail to detect a '172 flying
200 feet below. The newer ones are supposed to pick up the transponder
altitude, but probably have trouble keeping it matched to the
appropriate target. [I develop algorithms for the military to track
airborne threat targets and it can get complicated.] Does it vary the
altitude substantially when you are pretty sure there is only one threat
nearby?

I'm sure the plane itself will always act as a shield, depending on
where the target aircraft might be located...

Darrel Toepfer wrote in
:

Are you using the included antenna or an external one?

I'm using the included antenna still. There is no doubt that a dual
(high-low) antenna would be a big help. However, I often see the threat
aircraft pass directly in front of my plane and nothing from the ATD
until it is well past. The ATD antenna had a clear view - so I suspect
the problem is more with shadowing of the transmitting antenna.
Unfortunately, there is nothing that can be done about this on the ATD-
equipped aircraft.

I like the fact that the new model allows you to check your own
equipments ouputted signals...

True. Even the ATD-200 had a light to alert you that you were
responding to a ping. And my GPS tells me what my xpndr encoder is
saying. That still leaves faults in the xpndr itself (transmitting
false information) but not a big problem.

I'm sure the plane itself will always act as a shield, depending on
where the target aircraft might be located...

True. I know aircraft with Skywatch installed, complete with the top
and bottom antennas. That's a $20K+ system, and still they see aircraft
"appear and disappear" in certain quadrants. Heck, even ATC (which
typically has a better geometry) will see aircraft drop the Mode-C when
the plane is turning, or when some other part of the plane intervenes.
That could be fixed with a more sophisticated xpndr system, but no one
is going to propose that much money to upgrade the entire fleet.

-----------------------------------------------
James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
-----------------------------------------------

James M. Knox wrote:
Darrel Toepfer wrote:

Are you using the included antenna or an external one?

I'm using the included antenna still. There is no doubt that a dual
(high-low) antenna would be a big help. However, I often see the threat
aircraft pass directly in front of my plane and nothing from the ATD
until it is well past. The ATD antenna had a clear view - so I suspect
the problem is more with shadowing of the transmitting antenna.
Unfortunately, there is nothing that can be done about this on the ATD-
equipped aircraft.

But did they have a working transponder? g

Thanks for the reply...

Darrel Toepfer wrote in
:

However, I often see the
threat aircraft pass directly in front of my plane and nothing from
the ATD until it is well past. The ATD antenna had a clear view - so

But did they have a working transponder? g

Had to, or it wouldn't have picked them up at about a mile and just passed
my centerline. [Yes, if it only happened once in my lifetime, I would
think that maybe they say me, and that somehow made them realized they
hadn't turned their transponder on. But I have seen nearly identical
reactions on several occasions.]

-----------------------------------------------
James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
-----------------------------------------------

James M. Knox wrote:

I do have an ATD-200 in my plane and find it somewhere between
useful and toy. Toy, because it probably only identifies about 30% of
the traffic in a useful fashion (has a habit of not lighting up until
the traffic has passed G). Useful, because it sometimes does alert me
to look for traffic out in the boonies, when there hasn't been another
aircraft within 100 nm for the last 2 hours (hard to keep a good scan
going under those conditions). A large percentage of the time it gives
false alarms.



That just about NAILS it for what mine does for me.

I'm starting to get curious about what the newer ones can do, but to act
on that curiosity, I need to sell my ATD-200.

If anyone's interested, email me. I'd sacrifice it for $250 plus shipping.