V1 needs to be able to junk out k band signals

[Ace_Racer]

First off it is posts like this that make me extremely grateful K band is not a threat to me and only KA is. Second, I agree having a J for K band would be helpful and nice, but just like with KA band it may J out a real threat and that real threat could land you a real ticket! Just my two cents in the matter.

Ace

[TheTexan]

First off it is posts like this that make me extremely grateful K band is not a threat to me and only KA is. Second, I agree having a J for K band would be helpful and nice, but just like with KA band it may J out a real threat and that real threat could land you a real ticket! Just my two cents in the matter.

Ace

The point is you really can't J out a K-band false generated by a door opener or motion sensor they run good ole 24.150 GHz K-band and the only way you wont detect it is if it falls out of tune far enough that the signal falls outside of the bandpass filters (hope Im using that term correctly) on the RD or if it is an FMCW modulated source (V1 only there is one near my house that the x50 picks up and the V1 doesnt and no my K-band on the V works great). The only way to J out a threat is because the algorythm detects a 2nd or 3rd principle harmonic from the LO of a crappy RD approx. 11GHZ so the 2nd principle would be 22GHz and the 3rd would be 33GHz approximately (thats why Belscorts go nuts on POP when crapras are around). When the J algorythm detects this background harmonic you get the deedadoo and the flashing J. Since 22 Ghz is outside the bandpass for K you would even get an alert for that one. So in short you cannot J a false K signal because what everyone around here calls a false is legit radar that isnt a cop... Jimbonzz let me no if I f**ked anythign up in that post. Im still learning.

[alpinestars_2002795]

Im not saying that isn't true texan im just saying there has to be a better way than looking for 2nd and 3rd harmonics....there has to be a way to tell the difference. To distinguish what is legit and what isn't. It seems some dectors are better at it than others why? I think this just needs to be looked into new technology needs to be created how what where when why i dunno..?? Thats up for some genius at an ivy league school to think up. Just give me better k band filtering is all I ask!!


AlPiNe~

[jimbonzzz]

Jimbonzz let me no if I f**ked anythign up in that post. Im still learning.

You pretty much have the concept down.. :wink:

As for "filtering X and K band:
The signals from X and K Band motion sensors are electronically identical to police radar. Motion sensors use a gunn diode cavity oscillator, just like police radar guns do. There is no way to "filter" these sources without potentially hurting your protection against real police radar, and I don't think that is what the V1 is about.


There are a number of steps that detector manufacturers have taken to minimize false alerts. Here are some of the "filtering" methods they use for X and K band filtering ("city modes"):

1. Cut sensitivity: basically don't report the alert unless the signal is stronger than a certain threshold, or only report it visually but not audibly.

2. Don't report alerts shorter than a certain duration, for example, a detector might not reprt an alert unless a signal is present for more than 300ms. Some people believe that how fast a detector responds to a signal is related to the sweep rate, to a point this might be true. But what ultimately determines how fast most detectors respond is how these type of filters are set up in the unit's software. In some detectors, the signal must be present for two seconds or more to produce an alert.

3. Don't report alerts if there are multiple radar sources. Since motion sensors are frequently encountered in multiples, this might be a good indication that the source isn't as likely to be police radar.

4. Some detectors automatically adjust the alert "threshold" during operation, as the detector encounters multiple X or K-Band radar sources. If it sees multiple weak X and K band sources, it assumes it is in a city environment and adjusts the alert threshold accordingly.

5. More advanced detectors might use algorithms combining the three techniques above. They develop a statistical model of what is likely to be a false alert based on signal strength, number of sources, frequency, or any other information the detector has available.

6. Some detectors have other novel approaches to reduce falsing. For example, some Cobra models sense if the vehicle is stopped, and don't alert, since if you're stopped you probably aren't speeding.

Unfortunately, most of these methods have the potential to suppress alerts to actual police radar. Some might pose a greater statistical disadvantage than others.

IMHO, the V1 is able to filter X and K band very well using the Logic and Advanced Logic modes, along with the programmable options for K-Band. But one has to be cautious how they use these modes. You could potentially hurt your radar protection...

Jim

[alpinestars_2002795]

Jim your an expert on this subject. I agree with your wisdom on this. Although there has to be a better way that has not been found yet to filter the k band even better. It will come someday I know it will! Some dougie houser is stewing one up in his basement as we speak.


AlPINe~

[jimbonzzz]

Jim your an expert on this subject. I agree with your wisdom on this. Although there has to be a better way that has not been found yet to filter the k band even better. It will come someday I know it will! Some dougie houser is stewing one up in his basement as we speak.

I really hope so, sure would make things easier :wink:

[proudNMAmember]

It sure would!

[alpinestars_2002795]

Maybe them kids from Flordia State University could figure it out they seem to be smart suckers! I mean look what they did with that radar? By the way what ever happened to that please don't tell me they are thinking of moving that into production anytime soon....



AlPiNe~