Long range detection, close range J-out

[Motor On]

I got my 5th real LEO J-out in as many months today.

Picked up Ka, steadily climbing for 2miles, over the hill comes a local and the v1 pegs we both stop at a traffic light (opposite directions, both second row of cars in each direction.) Light turns green I get the J-out, start rolling through, no return of the Ka, I d notice he was on the radio at this point, and as I pulled away I saw the lights come on, presumably for a registraion or equipment violation.

If he shut the radar off shouldn't I have just had the signal die out, not J?

Would radio tramsmissions (800mhz) on his part be able to interfere witht he signal his radar was putting out (through harmonics or high power mobile radio in his car, it was the car radio so potenial for 45w Tx power through the same electical system off the same battery)

I used to get one Cobra J-out in a 6 month or longer time period, in the last 6 months or so I'm getting almost a daily dose of Js with somewhat increasing frequent real threat J-outs, How much of this is sign of a needed tune up? (Planning on sending it in soon anyways, but holding off as long as possible because just a short 20min trip w/out RD makes me feel so vulnerable.)

[robcollins5]

If he shut the radar off shouldn't I have just had the signal die out, not J?

Yes.

Would radio tramsmissions (800mhz) on his part be able to interfere witht he signal his radar was putting out (through harmonics or high power mobile radio in his car, it was the car radio so potenial for 45w Tx power through the same electical system off the same battery)

Not at all likely.

I used to get one Cobra J-out in a 6 month or longer time period, in the last 6 months or so I'm getting almost a daily dose of Js with somewhat increasing frequent real threat J-outs, How much of this is sign of a needed tune up?

This could go either way. Either your V1 is gaining sensitivity (wonderful!) or your algorithms are interpreting out of sync data intake....in dummy words. Send it in sir, restore confidence in your equipment.

[Samir]

(Planning on sending it in soon anyways, but holding off as long as possible because just a short 20min trip w/out RD makes me feel so vulnerable.)

Just have a second v1 as a backup. This way, you can send them in on rotation as needed.

The only downside to this (as I've learned) is that v1s can be different. I'm still running both of mine in a dual configuration trying to determine if the newer one is acting right or not.

[Gator Bite]

Oh boy. Where's RadarKid? Wait until he sees the beloved V1 locking out real LEOs... On Ka band no less...

[jdong]

The J-out is only applicable to Ka band. It is typically triggered by signals in the X band to Ku band range that are indicative of a local oscillator of another detector causing a false.

Other high-end detectors use this type of filtering too, just they silently retract alerts without an active J-out tone.

The motivation is often times it can take one second or much longer to determine if a Ka band threat or a junk detector. The J-out strategy allows the detector to alert early and pull back the alert if needed.

When you are dealing with IO or ambush type attacks, every second of reaction time is critical.

[foxx_good]

I just got a j out myself on a legit LEO running constant my v1 is only about 7 months old should i turn off pop or could it be out of tune already?

[jdong]

J-outs of real LEOs can happen with modern advanced-filtering detectors. Cheap radar detectors broadcast a lot of noise at 1/3 Ka frequencies, and the 3rd harmonics of those will trigger Ka band alerts.

Your detector actively looks for the presence of these fundamental frequencies, and if it finds a matching fundamental it assumes the Ka signal is a false.


Now, if "accidentally" or "intentionally" a 1/3 Ka signal is injected to exactly match a Ka band legit threat, a detector will more than likely junk out the signal. It would be an incredibly devastating strategy if a radar gun maker purposely puts out fake RD harmonics in addition to a police radar signal.

POP has nothing to do with these LEO J-outs. POP just adds additional J-outs for 67ms and below signals on top of continuous-wave J-outs.

Suck it up -- any time you filter you run the risk of false negatives. Any time you don't filter you run the risk of false negatives. If your detector went off on pulsed Ka band full strength once every 2 seconds because someone with an 11-band Cobra is within a block of you, I'm sure you'll start ignoring all of its Ka alerts.

[CJR238]

Oh boy. Where's RadarKid? Wait until he sees the beloved V1 locking out real LEOs... On Ka band no less...

LOL. its all dependent on what we want to complain about today, RK is just more consistent than most.

Other high-end detectors use this type of filtering too, just they silently retract alerts without an active J-out tone.

I haven't seen this, I get false blasts all the time from Cobra's (8500, I, ix).