Rating the High End Detectors

By Don Schroeder. Car & Driver, April 1997.

    Detector makers are in a pickle. The advent a few years ago of two more monitoring mediums Ka-band radar and lidarsent detector sales skyward in 1993 to more than 1.5 million units as nervous motorists scrambled to replace their old Xand K-band detectors with new ones that could seek out these new threats.

    Then sales declined, hovering between 1.3 and 1.4 million units a year. The detector-maker scene has changed, too. Two big manufacturers, Cincinnati Microwave and Bel-Tronics, announced a merger in December that will surely affect the market down the road. But that still leaves four major manufacturers and a few smaller companies, all competing for a slice of a matured market that demands a considerable investment in research and development just to stay in the game.

    As competition has intensified, there's been an explosion of detector features, from rearward lidar detection to voice alerts to LED display readouts. One detector in this test can sniff out the presence of the VG-2, a device used by police to detect radar detectors in Canada, Virginia, and D.C. (where detectors are illegal). That makes it a "radar detector detector detector," the thought of which made us laugh not too long ago.

    An odd new development on the scene is "safety radar." In this case, it is the authorities who are using K-band transmitters to alert motorists via their detectors to the presence of accidents, emergency vehicles in the area, or other road hazards. Some of the detectors in this test can alert their owners to the presence of safety radar, and a few of them can even tell the driver what the specific hazard is.

    There are two of these safety-radar systems. One is Safety Alert, and another is Safety Warning System, or SWS. Despite the wishes of safety-radar promoters (who also happen to be some of the detector makers), there are, in fact, few of these transmitters out there. Since your likelihood of encountering one remains near zero, we have elected to postpone covering and testing safety-radar systems until a future issue.

    The proliferation of features, though, doesn't change the detector's primary purpose: to provide an early warning of impending radar or lidar speed traps as clearly and reliably as possible without sending false alarms. Our tests concentrate on these capabilities. But first, a brief discussion of the speedmonitoring threats you face is in order. (For a full discussion, see our last detector test in the September 1995 issue.)

    Radar transmits a microwave beam toward your car and computes your speed from the change in the frequency of the signal as it is reflected back to the policeman's "gun." The guns operate in one of three frequency ranges-the X-band, at 10.500 to 10.550 gigahertz (GHz), and the Kband, at 24.050 to 24.250 GHz (the two most popular bands); or the rarely used but very wide Ka-band, which spans 33.400 to 36.000 GHz. Photo radar, wherein a camera set to operate automatically at the side of the road is triggered to photograph the license plates of speeding vehicles, also operates on Ka-band.

    Radar can be used while the patrol car is stationary or moving, sending its signal frontward or backward. Some police officers switch their radar guns on and measure speed continuously until they catch a speeder. Such "steady state" signals can easily be detected by even the worst radar detectors. Other officers switch their radar on only briefly to get instantaneous readings on specific cars. This "instant on" mode is more difficult to detect, and even the best detectors will save you only if other cars in the vicinity of yours are being clocked. If you're alone on the road and your detector records a solid hit, you're the target, and you're cooked.

    The Federal Communications Commission that regulates our airwaves also allows many devices-supermarket-door openers, burglar-alarm sensors, and others-to operate on the X-band and, to a lesser extent, the K-band. Many radar detectors also emit weak signals of their own on the Ka-band. These are the sources of most radar-detector false alarms. Detectors are equipped with switchable "city" modes that use filters designed to reduce the number of false alarms, usually at some cost to sensitivity on one or more bands.

    Lidar works on a different principle. A police officer directs short pulses of laser light (at a wavelength of 904 nanometers) at a targeted car, and the lidar gun computes a speed by timing the return of these pulses after they are reflected back from the car. Unlike broad radar beams, lidar is narrowly focused-at 1000 feet away, the strong portion of the beam is only about six feet wide. This narrow beam means the lidar gun must be aimed at a selected car, which gives Officer Bob the ability to pick one car out of a crowd to clock, which can't be done with radar. The typical clocking range is between 500 and 1200 feet. The better lidar guns can clock most cars in as little as a third of a second.

    A good detector will pick up lidar and warn the driver, but usually when that happens, you have just been clocked and will next see Officer Bob at your window. It's possible to get a warning from a lidar beam aimed at a car directly in line between you and the cop. It's also possible to get a warning if the gun can't grab your speed immediately, which can happen if your car doesn't reflect lidar easily. But both of these circumstances are rare.

    Our detector-testing techniques have been refined by the nearly one-dozen comparison tests we've performed over the course of 20 years. Before we begin, we buy as many of the detectors as possible on the open market to give every manufacturer as fair a shake as we can. (Only the Cobra and the Whistler were supplied by their manufacturers.)

    The tests are performed on the roads of the Chrysler proving grounds, which are free of stray radar noise. For radar testing, we use a 2.5-mile unobscured straightaway with the radar gun (X-, K-, and Kaband guns, one at a time) carefully placed down a grade beyond the end of the straightaway. This precise placement allows us to modulate signal strength down the straightaway, allowing full use of the 2.5 miles to distinguish detector sensitivity. Such a trap also allows us to avoid radar "hot spots" that occur on hills and rises, which can set off strong and weak detectors in the same location.

    The threat of instant-on radar makes a detector's ultimate sensitivity, or range, absolutely critical, because if your detector can't "see" the radar blips that occur when the officer clocks cars far down the road from yours, you could be facing an ugly surprise when it's your turn in front of the gun. So we test how far away the detectors sound their first alarms with the radar in both steady-state and instant-on modes. The sensitivity is measured with the detectors unfiltered in "highway" mode and with their most selective "city" filters engaged. In both modes, we drive toward the guns, noting at what distance the detectors sound their first audible alarm.

    For lidar, a straight-out range test (conducted like our radar tests) is neither feasible (it would demand impossible aiming accuracy) nor relevant (lidar isn't used at faraway distances anyway). What's important in a lidar detector is its ability to detect the fringe of a lidar beam aimed at another (or even your) car or the weak scatter bounced off another car. So we check each unit's ability to detect the edge of the beam.

    For this test, we lock in place an LTI Marksman lidar gun of the sort used by police and aim it at the dead center of a 32-foot-wide platform placed 1000 feet away from the gun. On the platform, we then place the detector behind a small section of windshield glass and move the detector laterally on the platform to determine its relative sensitivity to the beam's edge. This test is also performed with the detector facing rearward, to test its rear lidar vision.

    In a second lidar test, the detector is placed at the center of the windshield of a car that is driven at varying angles through a lidar beam aimed across the road. This allows us to determine the detector's angular field of view, both front and rear, while it's in a moving car. Police try to keep this angle as narrow as possible (because it reduces errors in speed readings). All the detectors can see lidar within the angular margin police use, typically no more than 15 degrees to either side of the car's trajectory. But we think the detectors with a wide field of view will pick up the beams within those angles more reliably. They are also more likely to pick up the rare reflection from other cars or reflective surfaces, which increases your admittedly slim chance of an advance warning.

    To check the radar/lidar detector's ability to fend off false alarms, we drive with the detector in both its highway and most filtered city modes through a 14-mile test loop in Ann Arbor. We also check the detector's propensity to set off, and be set off by, other detectors, as well as the manufacturer's claim that it is, or isn't, invisible to the VG-2 detector detector.

    Our numerical rating, computed from the test data on a spreadsheet, works like this: Of 100 points, a maximum of 50 are assigned to the detector's radar sensitivity (range), and a maximum of 10 are assigned to lidar sensitivity. Fifteen points are assigned to selectivity, a calculated score that compares the number of false alarms with the detector's radar sensitivity. (A detector that is so sensitive that it falses all the time isn't helpful, nor is one that never falses but never picks up any radar, either.) Another 15 points are assigned to the detector's ergonomics. (A detector with confusing warnings, difficult-to-find buttons, or a propensity to fall off the windshield all the time does not get high marks.) The city-mode score is another calculated number where we compare how well the city mode reduces false alarms without reducing sensitivity. Completing the score are five points for loudness of the detector's warning, with the loudest beep receiving five points and the others rated proportionally.

    The Valentine One has dominated every high-end detector test we've conducted since its introduction in 1992. Electronic refinements to the Valentine last summer have only strengthened its considerable lead ahead of the other detectors in our tests.

    No other detector comes close to this one for sniffing out radar. In its highway mode, the Valentine could find the most popular X- and K-bands from more than a mile and a half away, more than double the range of nearly all the other detectors. The Valentine One used to stumble when finding Ka-band, but no more. Its highway-mode Ka range is on par with the other two bands.

    Although its range was impressive, the Valentine was no more likely to distinguish false alarms than the other detectors. In its most sensitive "All Bogeys" mode, we counted 10 falses on our test loop, a moderate number. This detector offers two city filtering modes. The most aggressive mode cut the number to a quite respectable four.

    The Valentine's laser detection was also the best in this test. It's endowed with the widest angle of view from front and rear. At 1000 feet away from the lidar gun, it also detected the greatest width of the band.

    The Valentine has LED arrows on its face that tell you whether the radar is ahead of you or behind you. Live with this feature for a while, and you'll wonder how you ever lived without it. Also, a numeric display keeps track of the number of radar sources out there, a handy feature on routes you drive frequently. Otherwise, the Valentine's operation is straightforward. A rotary knob controls power and volume. Pushing the knob also changes the city filtering modes.

    We don't like having to memorize the nuances of the Valentine's LED patterns to figure out what the threat is. At least the Valentine's audible warnings are loud and clearly defined. The warnings are subtle at great distances from the radar gun and urgent close up, which makes determining your distance from the radar threat quite easy. The VG-2 detector detector cannot pick up the presence of the Valentine.

    This sophistication is reflected in the Valentine One's price of $399. The factory-direct sales arm offers no discounts. An optional lighter plug that darkens the detector's main display and offers one of its own is available for $69.

    The Valentine doesn't offer the slick styling and features of some of its competitors. Perhaps it should for its price. This issue pales, though, when your detector 's performance may be the only thing between you and Officer Bob at your window, with the hundreds of dollars in tickets and increased insurance premiums that follow. This is still the best protection money can buy by a long shot.

    With a list price of $299, or $219 at a discount, the 855STi is Bel's top-of-theline detector. It comes with many features, has decent ergonomics, and is capable in most respects. But a problem with falsing prevented its score from climbing higher.

    Although the Bel's X-band sensitivity was average, its K- and Ka-band performance was second only to the Valentine's. That laudable sensitivity comes, unfortunately, with many false alarms.

    On our 14-mile test loop, the Bel falsed an average of 16 times in the highway mode, which is not intolerable but explains the relatively low selectivity score. It was also susceptible to falsing from other detectors in the vicinity. In our test of false alarms in the most filtered city mode, the Bel worked poorly, sending an average of 13 falses.

    The Bel's front and rear laser sensors were on the weak side, detecting only 7.9 and 5.5 feet of beam width front and rear, respectively. The rear laser field of view was somewhat constricted at 36 degrees.

    There were many things we liked about the Bel, though, including its LED display and clear audio tones that leave no doubt what the threat is. The 855STi also comes with two city modes, dim and dark display settings for driving at night, and an automute mode that changes from loud beeping to soft clicking after a few seconds. The Bel distinguishes weak signals well, but its warnings never grow urgent enough-a solid warning tone would help here. The Bel's windshield suction-cup mount adds considerable bulk to the unit and must be adjusted with a screwdriver.

    The 855STi can be programmed to pick up SWS warnings with either a beep or a voice message, both of which are accompanied by a readout on the display. Bel claims the VG-2 cannot detect the 855STi's presence. Well, almost. The VG-2 detector sniffer can pick up the scent, but only from a distance of less than 10 feet. And that should be a short enough distance to keep Canadian, Virginian, and D.C. drivers out of trouble. The Bel is worthy because of its range, but keep in mind that its falsing tendencies mean its signals will require more interpretation on the part of the driver than those of the other detectors.

    The Solo is advertised as a batterypowered detector, but Escort engineers claim its performance is enhanced somewhat when its optional power cord is used. A fully cordless radar-detector test is in the works, but since the Solo is now Escort's premium detector, we included it in this test as well. We used the cord in our tests.

    The Solo's X- and K-band highway sensitivity was acceptable, but this detector's ability to pick up Ka-band is weak. The Solo could not detect instanton Ka-band radar until it was 450 feet away. If our test setup were a real trap, that would be too close.

    The Solo didn't false excessively. It offers four different city modes. We chose the most aggressive one that still allows some X-band sensitivity, and it reduced the eight average falses on the test loop to a single false, earning the Solo a full five points for its city-mode score. The Solo's low selectivity score is due to its modest overall sensitivity.

    The Solo's frontward view of the lidar field nearly equals that of the class-leading Valentine, but with its narrow 24degree rear field of view, the Solo may miss some rear laser pulses. Lidar sensitivity was adequate front and rear. This detector scored high in ergonomics. Its easily adjustable windshield mount is a marvel of simplicity. Band discrimination is excellent, with clear audible alerts and bright, easy-tosee LED letters that identify the incoming bands of X, K, Ka, and L (lidar). Warnings increase smoothly in urgency as the incoming signal increases in strength. The Solo can be custom-programmed with many options, from varying audible warning signals to disabling the squawky power-up test alerts. This requires consulting the owner's manual, but at least the settings are saved in the Solo's memory.

    The Solo responds to Safety Alert signals, but it discriminates and displays just four different hazards. Escort claims the Solo has a "Smartshield VG-2 rejection system," but the detector bloodhound can smell a Solo coming from nearly threequarters of a mile away.

    The Solo can be purchased directly from Escort for $200. The transformerequipped power cord is another $30. Its cordless capability and programmable customizing are endearing. If Ka-band or photo radar is in your locale, though, you might want to consider a different model.

    The $150 Cobra comes with the fewest features of the detectors tested here. It's the only detector without a coiled cord or memory settings, and its windshield suction cups are black rather than transparent. If the slant of your windshield requires adjusting the mount, it must be bent, an approach that hints of problems down the road. A visor mount is not available.

    This paucity of features has no bearing on the Cobra's function. Like the Solo, the Cobra does an acceptable job of sniffing out the common X- and K-band radars. It has a city mode that reduces X-band range only, which is appropriate since most falses are on X-band and most K-band alarms are the real thing. And like the Solo, the Cobra comes up short on sensitivity to Ka-band radar.

    The modest Ka range explains the Cobra's low selectivity score. We have no complaints with this detector's city mode (other than the fact that the owner's manual mentions not a word about it). It reduced the average number of false alarms on our test route from eight to zero.

    The Cobra's front and rear lidar fields of view are adequate, and its sensitivity to lidar is third best to the Valentine and the Whistler.

    The RSA-515 could employ better warnings. The round diodes that indicate a radar or lidar threat light up brightly enough, but you can't easily read the stenciled-on markings that indicate what is incoming, and the K, Ka, and lidar lights are nearly the same color. More aggravating is this detector's lidar warning, which is slow and hesitant at first, then inexplicably urgent seconds later. At least the loud, distinct audio tones are helpful in distinguishing the threats. Like the Valentine, the RSA-515 does not have an auto-mute function.

    This detector alerts you to the presence of Safety Alert radar by merely lighting all the band-warning diodes at once. It will pass by the VG-2 detector detector unnoticed, and it's also one of the least likely to produce false alarms from other detectors.

    The Cobra offers performance similar to that of the Escort Solo, and for $80 less, but it has far fewer features. This may be a good candidate for those who hate detector complication and falsing of any kind. But remember that it has limited Kaband capabilities.

    Whistler's high-end 1490 has many of the features you would expect from a $250 detector, including an informative LED display like the Bel's. It can detect the presence of the VG-2 detector detector. Its primary capabilities could stand some improvement, however.

    The Whistler's overall X-band sensitivity bests all the other detectors' but the Valentine's, but it is below average in picking up instant-on Ka-band. Its sensitivity to the prevalent K-band, although sufficient, was the worst of the bunch.

    The Whistler falsed an average of 10 times on our test loop, mid-pack for this group. The city mode reduces that number to six, but at the expense of cutting both K- and X-band sensitivity, a strategy we can't agree with since K-band warnings usually come from police radar.

    The Whistler needs no glasses to find lidar. Its lidar sensitivity was second to the Valentine's, while maintaining a generous field of view to the front and rear.

    The Whistler's VG-2 "detector detector detector" is intriguing. When the 1490 detects a VG-2 trying to locate it, which it can do more than a half-mile away, it sounds an alarm and engages a cloaking mode that hides it from the VG-2. We like the feature but note that it is only valuable where detectors are illegal.

    The Whistler's stiff bend-to-adjust windshield mount is hard to move by hand, although the standard visor mount is sturdy. The Whistler audibly distinguishes threats adequately, and the numerical LED strength meter is helpful. But the audible warnings are too strong with weak signals and become confused and garbled as the signal strength increases. The word "pulse" pops up on the visual display if the Whistler senses an abrupt instant-on signal, but we think such a feature is unnecessary if a detector's warnings are clear in the first place.

    Like the Escort and the Bel, the Whistler offers a dry-run "Teach" mode to help drivers acquaint themselves with different bands. It also detects both safety warning systems and calls out one of 60 possible messages on the LED readout. The Whistler has the quietest alarms of all the detectors we tested.

    The 1490 has many features and is sufficiently sensitive to both lidar and the popular radar bands. For its price, though, we expected better performance. Whistler is introducing a 1500-series of detectors that the company says provides just that.

    Although the Uniden finished last here, it is also the least expensive, with a list price the same as the Cobra's, and a discounted "street" price of less than $100.

    In highway mode, the Uniden has ample K- and Ka-band sensitivity. But the Uniden's overall sensitivity to X-band ranked last, providing a typical warning of only 1700 feet in the highway mode and even less in the city mode. Like a number of the detectors' city modes, the Uniden's provides an early visual warning but waits to sound the audible warning until a certain signal-strength threshold is reached. In most of the city tests, the Uniden's threshold was just a few hundred feet away from the gun-not enough warning. The Uniden's city mode also unfortunately reduces its sensitivity to K-band. This detector is probably best left in highway mode, where its sensitivity is always adequate.

    The Uniden was somewhat prone to falsing in the presence of other detectors, although the number of falses on the test loop averaged only 10. The Uniden could detect nine feet of lidar-beam width and had a field of view of 63 degrees. Looking forward, that is. Although it claims "360degree detection," this detector was virtually blind to lidar from the rear in our tests, despite its rear-facing lidar window.

    The Uniden's windshield mount seemed as well designed as the Solo's, until we used it for a few months and discovered that its flimsy metal support stem was on the verge of breaking in two. The power plug is the worst of the six detectors at staying put in the lighter socket. But the Uniden shows good design elsewhere. It properly distinguishes warnings with clear audible signals and a bright LED that changes color for the threat. Its city, audio, and mute buttons respond without the annoying hesitation of those of the Solo and Whistler.

    The Uniden does not distinguish among the SWS warnings it responds to; Uniden promises that capability is on the way with its upcoming 6599. It is invisible to the VG2, as Uniden advertising claims.

    If you're not too concerned about rear laser detection (we don't think you should be) and you leave this detector in highway mode, the Uniden offers adequate warnings on all four bands for a reasonable price. If you buy one, you might want to order extra windshield mounts while they're available.