Maybe someone can explain this...

First, I have been testing my 9500i with the GPS off right now after a recent bad lockout of actual police radar. I always used my x50 in City with loX when im in the city. I have only seen one legit X band in the area in the last few years but it is still a risk. Well, you cannot do loX on the 9500i but whatever... I have just been driving in City mode (you cannot do scanning +/- either which is annoying but oh well). The 9500i in city mode does seem to reduce the X a little (probably comparable to the X50 with full X on in city mode).

Anyhow, here is what happened in city mode w/o GPS:
The other night I made a late night trip to the local grocery store. Parked right next to the door, alerting 4-5 bars or so of K band. I mute it, leave it on, and go inside (it is hardwired to a constant source). I come back out get in the car and it is silent, no flashing red light, no K band on the display, just the scanning dot. I start the car and drive right up to the door, almost on the sidewalk... nothing. I push the mode button (which puts it in highway first, I believe) and it immediately jumps to 10bars, I toggle back through to city and it of course stays at 10 bars.

Any ideas what happened here? Is there some good reason why it would ignore the signal after [lets say] 5 minutes of half stregth constant signal?

Maybe I just have a questionable detector and it should be exchanged. The other day I saw a flash of red before it beeped, also with GPS off. Which kind of made me glad I mounted the smarcord where I can finally see it clearly.

Maybe there is a timed out feature, since it was going off on the same signal for so long.

X & K band door openers can be somewhat inconsistent, but im not sure why it would stop? It almost sounded like you’re in A mode? Maybe C mode also incorporates more filtering under 15mph?

There is a lag when switching from H to C, if I get a strong X false in H and change it back to C it will alert for 50sec or so then filter it out.

Are you sure it was going off for 5 minutes before turning silent.

I think the filtering is so cool.

Parked 50 feet away from a K-band automatic door, my detector in Auto mode alerted at low levels for a few seconds then went silent. When I switched to highway, it immediately alerted at mid-high levels non-stop. When I switched back to Auto, the lag was a few seconds.

I love how quiet this detector is. When it goes off, I pay attention.

I am sorry, but was your GPS on or off?

Also, I recently read that C and A work the same whether or not GPS is on or not, because the GPS runs in the background (i.e. you can only turn off the TrueLock function. Is this true?

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Originally Posted by 9500ier

I am sorry, but was your GPS on or off?

Also, I recently read that C and A work the same whether or not GPS is on or not, because the GPS runs in the background (i.e. you can only turn off the TrueLock function. Is this true?

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You are correct having the GPS on or off does not effect City or Auto. When I went to SML we did this exact test. The course had around 10 falses, and in Auto Mode the 9500i only alerted to 1 K and 1 X if I remember. When I did the same run again in City mode it filtered out both the K & X.

Back when I owned a 9500i (the 2nd time around) city mode filtered the crap out of X and K more so than any other RD I ever owned

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Originally Posted by happya$$

Back when I owned a 9500i (the 2nd time around) city mode filtered the crap out of X and K more so than any other RD I ever owned

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Yep, I get the same results with my 9500i in City mode. City mode makes my 9500i dead quiet in town unless I drive by a door opener which is located very close to the road or if my 9500i actually start alerting to an approaching K band police radar. City mode is bliss when I have my father in the car with me.

:-/ Hmm maybe I'm just irrationally paranoid from my decade or so of computer programming and studying security faults and other computing disasters, but I have real trouble handing over alert suppression type decisions to a software algorithm that (1) I am not informed precisely how it works by the manufacturer and am forced to guess about by empirical observation, and (2) I do not have the source code to look over for flaws in design or implementation.

I realize that the detector industry, as far as it goes against my philosophies, is tightly locked in patent competitions so #2 is a near impossible one to rectify, and #1 is probably also closely guarded for similar reasons.... but I'd rather feel more in control. I guess it's the same feeling as a pilot would have about a forced-on always-on autopilot system.

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Originally Posted by jdong

:-/ Hmm maybe I'm just irrationally paranoid from my decade or so of computer programming and studying security faults and other computing disasters, but I have real trouble handing over alert suppression type decisions to a software algorithm that (1) I am not informed precisely how it works by the manufacturer and am forced to guess about by empirical observation, and (2) I do not have the source code to look over for flaws in design or implementation.

I realize that the detector industry, as far as it goes against my philosophies, is tightly locked in patent competitions so #2 is a near impossible one to rectify, and #1 is probably also closely guarded for similar reasons.... but I'd rather feel more in control. I guess it's the same feeling as a pilot would have about a forced-on always-on autopilot system.

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Hi Jdong,

I totally agree with you. At least the radar detector manufacturers could provide some basic information about how the various sensitivity modes work!

Last summer I spent a few days testing the AutoScan mode used in Bel's Vector and RX series of radar detectors for filtering out X band door openers, just because I had to know how it worked. Then I tested the AutoScan mode in my STi and discovered that it also filters out pairs of very weak K band door opener signals when in Autoscan mode. A while back I decided to test the 9500i's TrueLock feature and its Auto Sensitivity mode, again just so that I would know how these features behaved with regards to radar. While I don't use TrueLock since I discovered that roughly 50% of the time it might lock out the K 24.125 or 24.15 frequency, I did discover that there is a lot more going on behind the scenes with the Auto Sensitivity mode. In Auto Sens mode, there appears to be an algorithm which looks for rapidly increasing radar signals versus your car's speed, generating an alert for what appears to be approaching police radar even when nearby door openers are being filtered out. This boosted my confidence in using the 9500i's Auto Sensitivity mode when driving around town since it does make the 9500i very quiet in town.

--Michael