dissenting.
In pertinent part, Code § 46.2-882 provides as follows:
The speed of any motor vehicle may be checked by the use of radar .... The results of such checks shall be accepted as prima facie evidence of the speed of such motor vehicle in any court or legal proceeding where the speed of the motor vehicle is at issue.
In a decision construing Code § 46-215.2, the predecessor to this statute, the Supreme Court held that the statute “does not eliminate the necessity for the Commonwealth to prove that the machine used for measuring speed had been properly set up and recently tested for accuracy.” Royals v. Commonwealth, 198 Va. 876, 881, 96 S.E.2d 812, 816 (1957). The Court also “‘recognized not only the necessity to carry out tests for accuracy on radar machines before and after they are used, but also the necessity for proving such tests by proper evidence in a subsequent prosecution for speeding.’ ” Biesser v. Town of Holland, 208 Va. 167, 169, 156 S.E.2d 792, 793-94 (1967) (quoting Crosby v. Commonwealth, 204 Va. 266, 268, 130 S.E.2d 467, 468 (1963)).
After the Court rendered the Biesser decision, the legislature amended the statute to address the proof problem. The statute as further amended now contains the following additional language:
In any court or legal proceeding in which any question arises about the calibration or accuracy of any radar, electrical, or microcomputer device as defined in this section used to check the speed of any motor vehicle, a certificate, or a true copy thereof, showing the calibration or accuracy of the speedom*669eter of any vehicle or of any tuning fork employed in calibrating or testing the device, and when and by whom the calibration was made, shall be admissible as evidence of the facts therein stated. No calibration or testing of such device shall be valid for longer than six months.
Code § 46.2-882. Although this paragraph of Code § 46.2-882 creates an exception to the hearsay rule to allow admission into evidence of a calibration certificate, it does not purport to determine the sufficiency of the evidence required to establish the accuracy of the radar.
The legislative intention is obvious on the face of the statute.
Manifestly [the] Code . . . was amended ... to obviate the necessity of having two troopers testify in every contested speeding case which involves the use of radar. It was the intention of the General Assembly to provide, in cases where any question arises as to the calibration or accuracy of any radio microwave or any other electrical device, that such accuracy could be shown by a certificate of the officers who conducted the tests of the device, and who had knowledge of its accuracy.
The statute contemplates that the speed of motor vehicles may be checked by radar; that the results of such checks be accepted as prima facie evidence where speed is an issue; and that persons may be convicted on the certificates filed in accordance with the statute. However, the statute must be strictly construed and there should be a full compliance therewith if a certificate is to be used as evidence. In prosecutions for speeding arising through the use of radar, the accuracy of the radio microwave, or other electrical device which measures the speed of a vehicle, is critical, for it is the reading reflected by this device which brings about the arrest and the conviction of a defendant.
Sweeny v. Commonwealth, 211 Va. 668, 670-71, 179 S.E.2d 509, 511-12 (1971).
If the Commonwealth relies upon evidence of speeding based on the readings from a radar device, the burden is on the Commonwealth to prove beyond a reasonable doubt the accuracy of the *670radar. See Biesser, 208 Va. at 168-69, 156 S.E.2d at 793; Farmer v. Commonwealth, 205 Va. 609, 611-12, 139 S.E.2d 40, 42 (1964); Royals, 198 Va. at 879-80, 96 S.E.2d at 814. In convicting Pearl Spears Gray, the trial judge specifically did not consider the results of the tuning fork tests. The trial judge ruled that the evidence proved the radar was reflecting the correct speed of Gray’s automobile. The trial judge reached that conclusion upon evidence that the radar had reflected the correct speed of the patrol vehicle when Holley tested the radar and upon the certificate in evidence that the speedometer of the patrol vehicle was accurate. In view of Officer Holley’s testimony, the trial judge erroneously concluded that the speedometer calibration alone proved beyond a reasonable doubt the accuracy of the radar.
In reviewing this issue, we are guided by the following principles:
It is well established that “[t] he judgment of the court sitting without a jury will not be set aside unless it is plainly wrong or without evidence to support it. However, a trial court’s conclusion based on evidence that is ‘not in material conflict’ does not have this binding effect on appeal.” A “trier of fact . . . ‘may not arbitrarily disregard uncontroverted evidence of unimpeached witnesses which is not inherently incredible and not inconsistent with facts in the record,’ ” and a finding under such circumstances presents a question of law, reviewable by this Court on appeal.
Watson v. Commonwealth, 17 Va. App. 124, 125-26, 435 S.E.2d 428, 429 (1993) (citations omitted).
Officer Holley, who operated and tested the radar unit, testified that he was “required” to perform two tests for internal calibration, one involving the use of tuning forks and one involving speed of a vehicle.2 He further testified that if the radar unit does not *671“meet all those criteria,” it may not be used. The officer’s testimony contains no further explanation regarding the requirement to conduct all these tests.
The officer also testified as follows:
Q ... . And the process that you described that you used on a daily basis, that you were trained to do to test this device, depends substantially, if not entirely, on the accuracy of those tuning forks, does it not?
A Yes. And like I said, everything, you can’t have one thing go wrong, it has to meet all, I mean, you have to make sure all the lights are working, the display shows up what it’s supposed to as well as the tuning forks. You can’t have ....
Q I understand, but on top of those other things being working, actually the tuning fork is critical to the testing of the machine, is it not?
A Absolutely.
Thus, the Commonwealth’s own evidence established a critical link between determining the accuracy of the radar and the tuning fork tests.
*672The trial judge had no knowledge whether the manufacturer of the radar required all of these tests to determine accuracy of the radar or whether the tests were administrative requirements. To the extent that the Commonwealth’s evidence was silent as to the reason for the requirements, the trial judge was not at liberty to disregard the officer’s testimony and to conclude that the accuracy of the tuning fork test was irrelevant to proof of the accuracy of the radar unit. The officer’s testimony established that he was required to use all of these tests as a measure of whether the radar unit may be used. The officer’s testimony, taken in context, reveals that the critical issue is whether the radar device passed each test. On the basis of the evidence proved at trial, the trial judge erroneously ruled “that the speedometer calibration is sufficient to prove the accuracy of the radar.”
The majority opinion misconstrues Thomas v. City of Norfolk, 207 Va. 12, 147 S.E.2d 727 (1966), when it interprets that case as establishing the principle that regardless of the other evidence the result of a tuning fork test ipse dixit proves beyond a reasonable doubt the accuracy of the radar set. The Court in Thomas clearly did not go as far as the majority perceives; the Court merely stated that a tuning fork test “is admissible as tending to prove the accuracy of the equipment.” Id. at 14, 147 S.E.2d at 728 (emphasis added). Any doubt about the intent of that language is resolved because in the very next sentence the Thomas opinion states that ii[i]n the absence of evidence to the contrary . . ., the trial court. . . had a right [to accept] the evidence of [tuning fork tests] as adequate proof of the accuracy of the radar set.” Id. (emphasis added). The officer’s testimony in this case presents evidence to the contrary sufficient to negate the prima facie case.
The Commonwealth also argues that Gray incorrectly asserts that the trial judge had no evidence of the calibration of the tuning forks. Although when Gray objected to the exhibit, the trial judge stated that he would “conditionally receive” the exhibit, the record establishes that the exhibit was not considered by the trial judge. When the trial judge conditionally received the document, the trial judge explicitly preserved Gray’s objection. The objection stated that the exhibit, which was notarized by a person whose title was not specified, and which purported to be a “copy” of the original, was not properly authenticated as required by Code § 8.01-390. See Ingram v. Commonwealth, 1 Va. App. 335, 340, *673338 S.E.2d 657, 659-60 (1986). See also Carroll v. Commonwealth, 10 Va. App. 686, 690 n.3, 396 S.E.2d 137, 140 n.3 (1990). On no less than three later occasions, Gray renewed the objection. Moreover, there was no proffer by the Commonwealth that later evidence would provide a connection that would clarify the admissibility of the exhibit. See Cutchin v. City of Roanoke, 113 Va. 452, 472, 74 S.E. 403, 406 (1912).
More significantly, however, the ruling of the trial judge at the conclusion of the case leaves no doubt that the trial judge did not consider the certificate as evidence. In making his ruling, the trial judge stated: “I think that the speedometer calibration is sufficient to prove the accuracy of the radar.” By its very terms, that ruling is declaratory of the judge’s intention to rely solely upon the certification of the speedometer’s accuracy.
For these reasons, I would reverse the conviction and dismiss the prosecution.
The officer testified that the radar unit is designed to operate when the patrol car is stationary or moving and that he is required to conduct various tests to verify the calibration of the radar. He also testified that the radar unit has two window monitors mounted in his patrol car: one that indicates the speed of the target vehicle and one that indicates the speed of the patrol vehicle.
The first test involves pressing a switch on the radar after it has been connected to a power source. That switch should cause the number thirty-two (32) to appear on both window monitors if the internal workings of the device are properly calibrated. The officer *671is then required to press a light display button. If the internal parts of the radar are functioning properly a series of the number eight (8) will appear on both window monitors and a series of lights will illuminate.
After testing the internal calibrations, the officer is required to test the radar while in the stationary mode by using two tuning forks. The vibration of one tuning fork should cause the target window monitor to display the number thirty-five (35). The vibration of the other tuning fork should cause the target window monitor to display the number sixty-five (65). He is then required to use the same tuning forks to test the radar unit while in the moving mode while his vehicle is stationary. During this test, the simultaneous vibration of the two tuning forks should cause the target window monitor to display the number thirty (30) and the patrol window monitor to display the number thirty-five (35).
Lastly, he is required to test the radar unit by comparing the reading on the window monitors against the speed as indicated on the patrol vehicle’s speedometer. To conduct this test, he must drive the patrol vehicle five miles per hour above the posted speed limit of the roadway on which the unit is to be operated and then five miles per hour below the posted speed limit of the same roadway.
The officer testified that the radar unit has to satisfy all of those criteria and that the tuning fork test was critical to establishing the accuracy of the radar unit. He also testified that he is required to perform these tests at the beginning of his duty shift and at the end of his duty shift.