To measure speed, the DPS radar receives radiation reflected from the car, and your radar detector is direct, so the radar detector is always able to detect the DPS radar much earlier in time than it will measure the speed of your car! You can actually detect an active DPS radar at a distance of up to 5000 m (under the best terrain conditions and weather), and the maximum distance of stable readings from a DPS radar is only about 400m.
But of course, it is important to know that a radar detector is necessary in 99% of cases in order to catch the reflected signal from vehicles ahead and terrain bumps – after all, a traffic police officer will not “shoot” at random for 3 kilometers trying to determine the speed of your car, but from a distance already possible to determine its radar. With the best uniden radar detectors you can have the best deal.
Therefore, one of the criteria for choosing a radar detector is its sensitivity and the possibility of maximum screening of false signals. By the way, these parameters basically differ radar detectors of different price groups.
Pros of types of amplifiers in a radar detector
All existing radar detectors of a radio signal use 2 types of signal amplification:
- Direct gain
- Heterodyne and superheterodyne amplification
- Direct gain in a radar detector
In the first case the oldest way to amplify the signal. The advantage is that the method is really passive – the radiation of the amplifier itself is almost 0. In this case, in countries where radar detectors are prohibited, this radar detector does not require the onboard function to hide the radar detector from VG-2 and other special DPS radars. It is also a plus that this type of amplifier catches a little interference (due to the very low sensitivity) and it is cheap to manufacture and set up. These advantages have grown into cons and manufacturers around the world have long abandoned this type of amplification, except for domestic manufacturers of radar detectors.
Amplification in a radar detector based on a local oscillator and a superheterodyne
The second method is the most technologically advanced and progressive, and is used in all mid-budget and top-priced radar detectors. Advantages are extremely high sensitivity and selectivity of frequencies.
The downside is that this device is active, i.e. it emits its characteristic radiation. Also, due to the high sensitivity, the percentage of interference increases, and it is necessary to tune the amplifier in terms of frequencies and create complex schemes for eliminating false interference. Also, unlike direct amplification schemes, in countries where these devices are prohibited, the presence of an amplifier shutdown circuit when exposed to a VG-2 detector is required.