How is POP mode engaged on various guns?

[jdong]

I saw a youtube video of a MPH handheld operating POP and I must say it looked like a PITA. It appeared like before shooting POP each time you had to push a button to turn on POP mode.

Is POP this inconvenient to use on all POP-capable guns?

[jimbonzzz]

I saw a youtube video of a MPH handheld operating POP and I must say it looked like a PITA. It appeared like before shooting POP each time you had to push a button to turn on POP mode.

Is POP this inconvenient to use on all POP-capable guns?

In the YouTube video, if they were pushing a button to turn on POP each time before a POP burst, then they were using it incorrectly. So the answer is NO, POP isn't that inconvenient to use on POP-capable guns.

If you want to see how POP really works on the MPH Z-25/Z35, see this video:
http://www.guysoflidar.com/videos/Z35Demo.wmv

[guit123]

whats the point of having pop in v1 if it cant detect even once?

[jimbonzzz]

whats the point of having pop in v1 if it cant detect even once?

It can: it detects 67ms K-Band POP and 67ms Ka-Band POP, and does it very well.

But NO detector provides useful alerts to the 16ms K-Band POP used in the MPH Z-25 & Z-35, although some might alert to it occasionally at point-blank range.

[KnightHawk]

The STi is the only one i know that does better with detecting POP 16ms. You'll get 3-4 out of 10 at "close range" and performs better than the V1.

[jdong]

Thanks for the info, everyone.

[jdong]

Thanks Jim, I just watched the video, nice parody of the original I saw ;-)

Yeah they definitely forgot to engage the gun into POP mode which explains the 100% detect rate.

Now my question is, why on earth didn't the 8500 next to it alert to 100% of the IO blasts like the V1 managed to? And apparently the previous test involved an RMR that alerted to less than 25% of K-band instant-on shots at point-blank range?

[jimbonzzz]

Now my question is, why on earth didn't the 8500 next to it alert to 100% of the IO blasts like the V1 managed to? And apparently the previous test involved an RMR that alerted to less than 25% of K-band instant-on shots at point-blank range?

Since POP wasn't actually on, the gun was basically quick-triggered. All detectors have software rules that they use for filtering to prevent false alerts, and these rules require that the radar signal must be present for a certain duration of time in order to trigger an alert, usually this is a number of milliseconds but can be a couple of seconds in some low-end detectors.

In testing of the V1, it generally alerts to 100% of K-Band signals with a duration of 100ms or longer(POP ON) or 200ms or longer (POP OFF). In testing of the Belscorts, the signal must be present for a much longer duration, usually 700ms or longer, for 100% detection.

[jdong]

Can an officer use quick-triggered speed readings in court? Definitely suppressing 100ms < t < 700ms alerts will cut down on falsing, but will that come at a cost?

[jimbonzzz]

Can an officer use quick-triggered speed readings in court? Definitely suppressing 100ms < t < 700ms alerts will cut down on falsing, but will that come at a cost?

Yes, I'm sure they could issue citations by quick-triggering if they wanted to, whether it would cause them problems in court, I'm not sure. Perhaps it goes against the principle of the cops "acquiring a tracking history", but it might be a difficult battle.

Suppressing alerts in that manner does come at a cost, just like almost every method of reducing falses. Of course the most obvious problem is alerting to quick-triggered guns, but it has farther-reaching implications.

When approaching a radar source in a moving vehicle, the signal is often very "choppy" due to multipath fade an other normal factors of radar signal propagation. The signal is not present long enough to trigger an alert until you're closer to the radar source. So in a general sense, the longer the time duration used in this type of filtering, the closer the detector must be to a radar source in order to "break through the filtering" in order to trigger an alert.

For example, let's say two detectors have identical sensitivity numbers when tested under lab conditions: a clean, steady CW signal. One might think they would get identical range in the real world. But let's say "Detector A" suppresses alerts to signals under a 100ms duration, and "Detector B" suppresses alerts to signals under a 500ms duration. Although the two detectors have identical lab sensitivity, under real-world conditions and on average Detector A will consistently alert further away from the radar source than detector B.