by Paul Bertorelli
If youve ever come close to swapping paint with another airplane-and probably even if you havent-youve likely considered traffic-awareness technology. Although sophisticated panel-mount traffic boxes have become more affordable, theyre still too expensive for many owners to consider, thus a small market for portable transponder detectors has emerged.
The latest is a diminutive product from SureCheck Avionics called the TS Micro. This device-about the size of a cigarette pack-builds on SureChecks two earlier products, the TrafficScope VR and VRX. At $299 purchased directly from SureChecks Web site, the Micro is not only the smallest traffic detector, its also the cheapest.
As we go press, SureCheck is about to drastically reduce the price on its top-of-the-line TrafficScope VRX from $985 (discounted by Eastern Avionics) to $785, better to compete with the ProxAlert R5 and Monroy ATD-300.Further, in late December, SureCheck told us a new version of the Micro would be available, offering both ships power and battery operation.
Given the fact that the price spread between the most expensive portable-now the ProxAlert-and the Micro is more than $700, can such an inexpensive device really be worth buying? What do you give up by settling for the cheapest option?
We found that the answers to these questions arent as obvious as we expected them to be when we embarked upon a multi-flight round of testing to evaluate the TS Micro. All of the portable traffic minders fall short of perfection in that they tend to miss traffic you might wish to see, they mis-estimate range and none offer any azimuth data. In the end, youre left to scan the entire horizon when one of them squawks an alarm.
On the other hand, if you buy one of these gadgets, you probably did so because you werent prepared to spend $6000 to $20,000 for a full-blown panel system and you understand a portables performance will be compromised.Thats another way of saying you get what you pay for and that definitely applies to the TS Micro.
A Slip of a Thing
Thanks to its small size, the TS Micro may be the ideal choice for an owner who rents airplanes or a pilot contemplating the purchase of one of the new light sport aircraft. At 3-3/4 inches long by 2-1/4 inches wide and 1 inch high, it occupies a tiny slice of real estate on the glareshield and unlike the other larger portables, it doesnt block the view. A 2-inch rubber-ducky type antenna attaches to a jack on one side of the unit. Controls are about as simple as these things get. Theres a three-position toggle switch for power and dimming and a set of color bars graduated by color. (More on that later.)
The version of the Micro we flight tested was battery operated only while the follow-on model has a ships power option. You need to mind both the kind of batteries used and, probably, always carry spares, if ships power isnt an option. Because of its relatively high power consumption, the Micro uses only NiMH rechargeables, four of which are supplied with each unit, along with a wall-mount charger as a $34.95 option. (Its the Rayovac charger we evaluated in our battery article in the December, 2004 issue.)
The device lacks reverse polarity protection so loading the batteries incorrectly may damage it and the fix isnt covered by the warranty. The battery door is easy to remove but the polarity indicators are difficult to read in normal light, let alone a dark cockpit. Marking them with ink would help. Our rundown tests indicate that the Micro runs about five hours or so on pair of fresh batteries but that life will be reduced in congested airspace, where the device is constantly engaged by distant transponders. We were not able to fly in areas congested enough to evaluate battery life under constant-reply conditions. The display dim switch extends battery life at night, according to SureCheck. Theres also a battery condition indicator and a low-battery warning light.
One nuisance factor is that youll need to have fully charged NiMH batteries constantly at hand. Throwing in a couple of alkalines wont provide good performance, since, as noted in our battery article, NiMH batteries have a voltage discharge curve flatter than that of alkalines, so theyll last only about 20 percent as long as NiMH batteries.
Further, NiMH batteries have a higher self-discharge rate than other batteries so when you depart, youll need to remember to charge up a couple of sets. (That takes about 15 minutes per set of two batteries, using the Rayovac charger.)
As reader Mike Palmer observes in the letters section of this issue, NiMH batteries require some sort of management scheme. If you want to have fully charged batteries always available, consider using them in two or more devices, with alkalines reserved for seldom-used gadgets such as back-up GPS, flashlight or handheld radios that can use batteries with either a steep or a flat discharge curve. Using ships power obviates these concerns, of course.
No Bells or Whistles
In keeping with its low price, the Micros featureset is minimal. What it does, it does adequately but it doesnt do much. Its basically a passive transponder receiver and upon detecting a signal, it makes a stab at range estimation based on relative power. Although portables have improved in their ability to do this, the limitations are obvious. How can it distinguish between a weak transponder close in and a more powerful one at a distance? Or a transponder at mid-distance whose antenna is slathered in belly oil?
The answer is that it cant always but, nonetheless, we found its range estimation to be adequate to the task, which is merely to draw your attention to traffic nearby. The Micro annunciates range through a series of color bars, with the threat increasing from green-on the far left-through yellow and then red on the far right.
The display is logical and easy to interpret, but its far from consistently accurate at distances greater than a mile. We found that when traffic approached one mile or less in range, the Micro was more consistent in illuminating the red color bar, which is the max threat situation and the point at which youd want to have your eyes outside of the cockpit.
We constructed several trial scenarios. On two flights, we had another pilot fly a Cessna 152 target aircraft at various ranges while we made numerous passes at it from all points of the clock. We flew passes above, below and at the same altitude to test the Micros sensitivity. Second, we flew three flights through Tampas busy Class B airspace, observing how the Micro picked up-or failed to pick up-distant traffic.
For range comparison, we used the TIS system provided by our Garmin 330 transponder and displayed on a Garmin GNS530. We also carried along another portable, a ProxAlert R5 loaned to us by Eastern Avionics. On the flyby set-ups, the Micro was at times impressive, at times disappointing. When the TIS system would place the target accurately at 3 miles, the Micro would appear at times not to see it. Then, as we closed the distance, the range would suddenly drop to the red 1-mile warning. The ProxAlert performed similarly but it tended to considerably underestimate range, at one point displaying a range of 0.5 miles when the TIS had the target at 2 miles.
Both devices miss traffic but miss has to be defined. At some point during the closing runs, both would eventually acquire the target . Only on rare occasions-once each for each device-were targets missed entirely. On one flight, the Micro spotted a Cessna 172 maneuvering 1000 feet above us and accurately tracked its range to within a mile. The ProxAlert never saw the traffic. Returning to homebase, the ProxAlert detected traffic in the pattern 3 miles away from the airport but the Micro never showed it. Otherwise, target detection at some range was better than 90 percent for both.
More sophisticated traffic detectors such as SureChecks TrafficScope VRX, the ProxAlert R5 and Monroys ATD-300 attempt to provide accurate range information via digital display. Although our tests suggest that the absolute range estimates are questionable for all these units, the trend information is useful. In other words, if the range is trending up, the threat is less acute. If its trending down, you need to keep your scan alive.
None of the portables provide target azimuth data, but the more expensive models do provide relative altitude data based on Mode-C replies from detected targets. Thats useful in confining your scan to an area above or below the airplane or ignoring the target if its 1000 feet above or below your altitude.
The Micro does none of this and for under $300, we dont expect it to. Range trend information is iffy, at best, in our view. In comparing it to the accurate range data provided by TIS, we found that the Micro would sometimes show a logical, orderly range countdown as the target came closer. But it would often appear to jump from one range indication to another and, occasionally, drop the target entirely. Once the red 1-mile range is illuminated, however, the Micro usually holds onto the target.
All of the portables have proven significantly blind to traffic behind the host aircraft, due to signal blocking, unless an external antenna is used.Here, the Micro did quite well, more often detecting traffic behind the airplane than did the ProxAlert.
At $279 discounted by Eastern, is this thing worth buying or should you spend three times as much for one that has more features? Frankly, the Micro performed respectably but it wouldnt be our first choice in portable traffic awareness equipment. While its cheap, the problem with portables is that lacking azimuth, the best they can do is provide relative altitude information and reasonably reliable range and range trend information. The Micro gives up even that.
In fairness, the Micro can be reliably expected to see most of the traffic most of the time. Although it misses targets, so do the more expensive devices. And although the Micros ranging is inconsistent, its adequate where it matters: within 1 mile. But without relative altitude information and trend data, youre only a baby step past having no electronic eyes at all. If your expectations in traffic awareness are modest, the Micro may meet them.
If youre willing to spend more money for a portable traffic device and you want the sophistication of digital display ranging and relative altitude, the market has suddenly changed with SureChecks price reduction on the VRX to $785 discounted, evidently in response to competition from ProxAlert and the Monroy ATD-300, which sells for $789 discounted. SureCheck has also dropped from its line the less capable TrafficScope VR, which didnt provide relative altitude data.
Which is the top pick among these three? All three perform about equally, although there are differences in features. The SureCheck VRX has a built-in onboard altitude sensor so it will display relative altitude when the host aircraft Mode-C isnt being received. (That happens fairly often.) Further, the VRX is the only one of the three that will run on both batteries-alkalines, not just rechargeables-and ships power. The Monroy ATD-300 is the smallest of the bunch and our tests last year (Aviation Consumer, April 2004) revealed that it had a slight edge in traffic detection over the SureCheck.
But the performance difference might be so elusive as to be outweighed by the TrafficScopes other features and the fact that the Monroy has a software quirk or two, can only run on ships power and has no onboard pressure sensor. Among the higher priced portables, in order of preference, we would pick the Monroy and SureCheck about equally, with the ProxAlert third, but only because of its now higher price. (Eastern sells it for $989.) We dont think a buyer would go wrong with any of these three choices.