The BMW UUC Digest Volume 3 : Issue 337 : "text" Format Messages in this Issue: Re: NOW homebrew laser jammers The truth, was: laser jammers Re: NOW homebrew laser jammers Re: NOW homebrew laser jammers Re: M62 leaking chain cover Re: M62 leaking chain cover FS: 524td crank and JE Pistons Re: Tom Swift laser doohickey Re: Tom Swift laser doohickey
---------------------------------------------------------------------- Date: Tue, 12 Dec 2006 09:59:32 -0500 From: "Dennis Liu" <[EMAIL PROTECTED]> To: <[email protected]> Cc: "'Jason Kay'" <[EMAIL PROTECTED]>, "'Gary Derian'" <[EMAIL PROTECTED]> Subject: Re: NOW homebrew laser jammers Message-ID: <[EMAIL PROTECTED]> Forgive my skepticism, but, Paul, that cannot possibly be right. If what you said were true, then cops wouldn't need all of this fancy equipment. No radar, no lidar, no vascar, no airplanes, nothing. He could just sit on the side of the road, then decide to pull you over and write tickets based on nothing more than his estimation. AND, if what you said were true, then none of the defenses to tickets written with radar would work - but we all know that they have worked for many of us in the past. Sure, you're right in that the officer's estimate may be ADMISSIBLE, but admissibility is far, far away from creating a legal conclusion. (My statement that I was driving only 17 mph is equally admissible; the judge may not put any weight to it, but it IS admissible.) So you might think we're super-keeno-dweebazoids, or you might think that we're anarchists out to create havoc on the highway, or you might think we're just unsafe ba$t*rds making life worse for the law-abiding folks, but your CONCLUSION is erroneous. Vty, --Dennis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul M. Moriarty Sent: Tuesday, December 12, 2006 12:10 AM To: [email protected] Cc: 'Jason Kay'; 'Gary Derian' Subject: Re: [UUC] NOW homebrew laser jammers You guys seem to be overlooking one thing. In the eyes of the court, a police officer's estimate of your speed is considered the testimony of a trained professional and therefore admissable. So even if your super-keeno-dweebazoid laser jammer throws off his reading, all he has to do is testify that he esitmated your speed to be whatever. Unless you hire a good attorney (which I might consider for a triple digit offense), you're going down. - Paul - Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ------------------------------ Date: Tue, 12 Dec 2006 10:09:21 -0500 From: Matt Murray <[EMAIL PROTECTED]> To: [email protected] Subject: The truth, was: laser jammers Message-ID: <[EMAIL PROTECTED]> We knew this, Dennis. :^) Matt Murray ----- Original Message ----- > So you might think we're super-keeno-dweebazoids, > --Dennis ------------------------------ Date: Tue, 12 Dec 2006 07:19:01 -0800 (PST) From: P Kroon <[EMAIL PROTECTED]> To: [email protected] Subject: Re: NOW homebrew laser jammers Message-ID: <[EMAIL PROTECTED]> Paul/Dennis: You're both right, and I think are largely arguing the same thing. The cops estimation of your speed is clearly admissible. Your estimation of your speed is also admissible. In the end, it will come down to whomever the judge believes more. Problem is, given no other *really* good testimony (and I mean *really* good), the judge is likely to side with the cop based on his/her "years of service and training." Case in point, a couple years ago I fought a ticket for failing to yield while merging onto a rotary. I established that the cop had an obstructed view and couldn't actually see how close I was to the truck I merged in front of and that the truck I merged in front of didn't make any emergency maneuvers. I also got in the record that I previously was a cop for 4 years (and therefore also had training estimating distances and speed). In the end, the judge stated that the cop had more years of service/training than I had and ruled against me based on this fact alone (despite the cop's admittedly obstructed view). -Paul ----- Original Message ---- From: Dennis Liu <[EMAIL PROTECTED]> To: [email protected] Cc: Jason Kay <[EMAIL PROTECTED]>; Gary Derian <[EMAIL PROTECTED]> Sent: Tuesday, December 12, 2006 9:59:32 AM Subject: Re: [UUC] NOW homebrew laser jammers Forgive my skepticism, but, Paul, that cannot possibly be right. If what you said were true, then cops wouldn't need all of this fancy equipment. No radar, no lidar, no vascar, no airplanes, nothing. He could just sit on the side of the road, then decide to pull you over and write tickets based on nothing more than his estimation. AND, if what you said were true, then none of the defenses to tickets written with radar would work - but we all know that they have worked for many of us in the past. Sure, you're right in that the officer's estimate may be ADMISSIBLE, but admissibility is far, far away from creating a legal conclusion. (My statement that I was driving only 17 mph is equally admissible; the judge may not put any weight to it, but it IS admissible.) So you might think we're super-keeno-dweebazoids, or you might think that we're anarchists out to create havoc on the highway, or you might think we're just unsafe ba$t*rds making life worse for the law-abiding folks, but your CONCLUSION is erroneous. Vty, --Dennis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul M. Moriarty Sent: Tuesday, December 12, 2006 12:10 AM To: [email protected] Cc: 'Jason Kay'; 'Gary Derian' Subject: Re: [UUC] NOW homebrew laser jammers You guys seem to be overlooking one thing. In the eyes of the court, a police officer's estimate of your speed is considered the testimony of a trained professional and therefore admissable. So even if your super-keeno-dweebazoid laser jammer throws off his reading, all he has to do is testify that he esitmated your speed to be whatever. Unless you hire a good attorney (which I might consider for a triple digit offense), you're going down. - Paul - Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ____________________________________________________________________________________ Want to start your own business? Learn how on Yahoo! Small Business. http://smallbusiness.yahoo.com/r-index ------------------------------ Date: Tue, 12 Dec 2006 10:28:22 -0500 From: "Dennis Liu" <[EMAIL PROTECTED]> To: <[email protected]> Subject: Re: NOW homebrew laser jammers Message-ID: <[EMAIL PROTECTED]> Paul K, you and I are definitely in agreement. But the larger point that the other Paul made, and his conclusion in particular, is incorrect. Sure, as Brett said, you could end up with a judge or magistrate that could choose to ignore everything you say and just go with what the cop says. But, in the case of a cop sitting on the side of the road shooting laser, that is a DIFFERENT scenario. First, the cop needs to explain to the judge that his technology did not work. So now the only evidence of your malfeasance is the cop's opinion. And he has to form that opinion from the side of the road, looking at oncoming traffic. Which is HUGELY suspect. He might be able to say that you were going faster than other traffic, he might even give a guesstimate of you going X mph. But you can starkly state that you were watching your speed, especially when you noticed the officer on the side of the road, and your speedometer indicated that you were traveling at 65 mph. The cop does not have laser evidence, and he did not pace you for .1 to 1 miles, with a certified speedometer. I think in most cases, the court would find in your favor. ***Not to mention that the cop isn't likely to pull you over in the first place, if he can't get a reading from you. It's far, far, far easier to just wait and snatch the car behind you who he CAN get a laser reading.*** My point was only that that conclusion that a Blinder or somesuch is useless because you'd be found guilty solely based on the cop's estimation is, in a word, incorrect. Vty, --Dennis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of P Kroon Sent: Tuesday, December 12, 2006 10:19 AM To: [email protected] Subject: Re: [UUC] NOW homebrew laser jammers Paul/Dennis: You're both right, and I think are largely arguing the same thing. The cops estimation of your speed is clearly admissible. Your estimation of your speed is also admissible. In the end, it will come down to whomever the judge believes more. Problem is, given no other *really* good testimony (and I mean *really* good), the judge is likely to side with the cop based on his/her "years of service and training." Case in point, a couple years ago I fought a ticket for failing to yield while merging onto a rotary. I established that the cop had an obstructed view and couldn't actually see how close I was to the truck I merged in front of and that the truck I merged in front of didn't make any emergency maneuvers. I also got in the record that I previously was a cop for 4 years (and therefore also had training estimating distances and speed). In the end, the judge stated that the cop had more years of service/training than I had and ruled against me based on this fact alone (despite the cop's admittedly obstructed view). -Paul ----- Original Message ---- From: Dennis Liu <[EMAIL PROTECTED]> To: [email protected] Cc: Jason Kay <[EMAIL PROTECTED]>; Gary Derian <[EMAIL PROTECTED]> Sent: Tuesday, December 12, 2006 9:59:32 AM Subject: Re: [UUC] NOW homebrew laser jammers Forgive my skepticism, but, Paul, that cannot possibly be right. If what you said were true, then cops wouldn't need all of this fancy equipment. No radar, no lidar, no vascar, no airplanes, nothing. He could just sit on the side of the road, then decide to pull you over and write tickets based on nothing more than his estimation. AND, if what you said were true, then none of the defenses to tickets written with radar would work - but we all know that they have worked for many of us in the past. Sure, you're right in that the officer's estimate may be ADMISSIBLE, but admissibility is far, far away from creating a legal conclusion. (My statement that I was driving only 17 mph is equally admissible; the judge may not put any weight to it, but it IS admissible.) So you might think we're super-keeno-dweebazoids, or you might think that we're anarchists out to create havoc on the highway, or you might think we're just unsafe ba$t*rds making life worse for the law-abiding folks, but your CONCLUSION is erroneous. Vty, --Dennis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul M. Moriarty Sent: Tuesday, December 12, 2006 12:10 AM To: [email protected] Cc: 'Jason Kay'; 'Gary Derian' Subject: Re: [UUC] NOW homebrew laser jammers You guys seem to be overlooking one thing. In the eyes of the court, a police officer's estimate of your speed is considered the testimony of a trained professional and therefore admissable. So even if your super-keeno-dweebazoid laser jammer throws off his reading, all he has to do is testify that he esitmated your speed to be whatever. Unless you hire a good attorney (which I might consider for a triple digit offense), you're going down. - Paul - Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ____________________________________________________________________________ ________ Want to start your own business? Learn how on Yahoo! Small Business. http://smallbusiness.yahoo.com/r-index Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ------------------------------ Date: Tue, 12 Dec 2006 09:30:14 -0800 (PST) From: Ivan Demkovitch <[EMAIL PROTECTED]> To: [email protected] Subject: Re: M62 leaking chain cover Message-ID: <[EMAIL PROTECTED]> Brett, thanks for information. Will I need to have crank holder to remove lower cover? I'm thinking since I will be there mine as well replace all gaskets.. Also, what is your input on replacing gaskets. Like oil pan gasket. I replaced it 2 years ago and it's good. Now, if I take oil pan out, is it necessary to replace gasket again? Ivan Date: Mon, 11 Dec 2006 20:48:08 -0800 (PST) From: Ivan Demkovitch <[EMAIL PROTECTED]> To: [email protected] Subject: M62 leaking chain cover Message-ID: <[EMAIL PROTECTED]> Hi! I have 97' 540i/6 with 170k miles. It has oil leak that starts getting worse with time. I see puddle of oil about 4 inches in diameter after every night in garage. Today I inspected everything with a mirror and it seem to be that upper covers leaking oil. I replaced leaking Valve covers 2 years ago and they look good. So.. I need word of wisdom on this new problem. According to Bentley since I'm not going to touch chains - I won't need any special tools but crank holder. I need to replace valley pan gasket and radiator(preventive), so it will be 1 decent size job. I'm wondering if there any tricks doing that job or everything straight forward. Also, what else I need to replace while doing that? I have all new intake gaskets and I will need to replace valve cover gaskets again, as it's not good idea to reuse them.. THanks, Ivan ------------------------------ Date: Tue, 12 Dec 2006 13:59:26 -0500 From: KMS- Brett Anderson <[EMAIL PROTECTED]> To: UUC Digest <[email protected]> Subject: Re: M62 leaking chain cover Message-ID: <[EMAIL PROTECTED]> You don't want to remove the lower cover. BMW says that job takes 14 hours, so someone who's never done it before is likely to take 30 hours. It is extremely rare for the lower cover to leak. If you remove the oil pan, you will need to replace both gaskets. Brett Anderson KMS Ivan Demkovitch wrote: > Brett, thanks for information. > > Will I need to have crank holder to remove lower cover? I'm thinking > since I will be there mine as well replace all gaskets.. > > Also, what is your input on replacing gaskets. Like oil pan gasket. I > replaced it 2 years ago and it's good. Now, if I take oil pan out, is > it necessary to replace gasket again? > > Ivan > > ------------------------------ Date: Tue, 12 Dec 2006 10:02:29 -0800 (PST) From: Kyle Sanchez <[EMAIL PROTECTED]> To: [EMAIL PROTECTED], [EMAIL PROTECTED], "Private.BMW.PARTS" <[EMAIL PROTECTED]>, UUC BMW LIST <[email protected]>, Yahoo E30 Group <[EMAIL PROTECTED]> Subject: FS: 524td crank and JE Pistons Message-ID: <[EMAIL PROTECTED]> Selling my stroker parts to fund my next project: First up: Complete set of six JE alloy forged pistons from Top End Performance. Size is 85mm (1mm overbore) for stroker engines. If you have a 2.7 liter stroker, this will bump you up to 2.8 liters. Has 10.0:1 compression and comes complete with wrist pins, Total Seal rings, and eta connecting rods. Runs on street gas but higher octane is obviously required. USED in good shape $600 takes them. Retail price is $950 without the rods. Pictures: http://home. comcast.net/ ~rj.dk.sanchez/ E30.PISTONS. jpg http://home. comcast.net/ ~rj.dk.sanchez/ E30.PISTONS2. jpg A 524td crank. I bought this crank over 3 years ago. I haven't used it. In very good shape. Great crank for a turbo stroker. $400 OBO Pictures: http://home. comcast.net/ ~rj.dk.sanchez/ 524TD.CRANK. jpg http://home. comcast.net/ ~rj.dk.sanchez/ 524TD.CRANK2. jpg Shipping is not included. Reply to me at bmw_nine2510 at yahoo dot com Replace nine with "9". ____________________________________________________________________________________ Have a burning question? Go to www.Answers.yahoo.com and get answers from real people who know. ------------------------------ Date: Tue, 12 Dec 2006 12:05:40 -0600 From: "Robert M. Ellsworth" <[EMAIL PROTECTED]> To: <[email protected]> Subject: Re: Tom Swift laser doohickey Message-ID: <[EMAIL PROTECTED]> Advance warning of laser via backscatter, etc. is probably a good idea always. And slowing down (using proper braking technique and attention to surrounding traffic, of course) is almost ALWAYS an appropriate response to 904nm illumination in uncertain circumstances... I could argue it's an appropriate response in ANY uncertain circumstances... Blinders around the license plate frame make the 'most' sense if you're going to use them, as that's, from my memory, where most officers are trained to aim in order to avoid issues with improper targeting. The translucent 'veil' is material that tries to do two things: scatter the light to reduce return-path intensity, and absorb light of the wavelengths used in lidar (usually in the 904nm range, historically, but I'd easily expect polyspectral devices "soon" if not already...) Note that if you wax the stuff, it stops doing its jobs almost instantly -- I would treat it as if it were 'flat black finish' if applying any detailing potions ;-} Any even half-*ssed lidar designer is going to be able to adjust the illumination sensitivity of his detector over a fairly wide range -- and modulate the power of his emitter (through variable filters if not directly at the diodes) so that the SNR of the calibrated pulses climbs up out of the "IR background". That clearly implies that you have to MODULATE the 904nm diodes in the same way that... shall we say, 'certain people' back in the day knew how to modulate X-band frequency so that it toggled the 'fastest return' logic on artificial-stupidity radar guns to some impossible speed range. (Note: NOT 'limits of display', or whatever, just enough that if the officer is dumb enough to be greedy and cite the 'actual' speed, you can prove him a liar, and if he tries to derate it, make him prove it... Remember that a laser radar isn't a SPEED measuring device using Doppler shift, it's a sequential-distance-measuring device that is dependent on a timing function to derive speed. This is why the sort of fast-braking-to-throw-off-lockup technique that can work with radar doesn't work with lidar -- two distance readings is enough to get you a speed, five is enough to give you the 4x verification dreaded by defense attorneys. So what an 'advanced' Tom Swift blinder modulator will do is send appropriately shifted pulse information *at high brightness* THAT VARIES WITH TIME AND BRAKING EFFORT right from the instant the 904nm light is detected. (Useful, of course, if you can pick up the pulse frequency the device uses and jam on that riff, but as noted by the time you decode the pulsetrain from a strong event, the device has already derived your speed...) You have at least two flavors of response: make it look like you're covering far less distance per pulse, or make it look like you're accelerating wildly fast (probably a sign to the lidar's internal logic that it's heterodyning two 'equal' returns). Personally, I'd do a little homework aka industrial espionage to see if there are 'consistent' pulsetrain timings in use for given makes of guns, and build my emitter driver base rate accordingly... Oh yes: look at the detection cone an officer would be using, and spec your divergence accordingly. As a first estimate, use the angle where cosine error for the sequential distance measurement would start to show significant speed error... and consider that a reasonable place to shoot lidar is going to be overpasses and so forth where the divergence is VERTICAL, remembering that cosine error in lidar UNDERSTATES your true speed (in a manner that is easily mathematically correctable from video or even derived geometry at trial time...) If, and I emphasize if, I were thinking of building such a thing, I would use several different cones of divergence, and perhaps rig the sets with selective switching (so you had the option of activating just the ones corresponding to an illumination source, and not false everything in scatter LOS from dust particles in the atmosphere or whatever ;-} Remember, gentlemen, the correct answer is not overkill, it's modulation; "Everything in modulation", to perhaps paraphrase Aristotle... this may also prove an advantage, albeit transitory, when the modern analogues to the Spectre III start looking around for high-intensity 904nm where it shouldn't be as I fully expect will soon be the case. Interesting little point, perhaps: Having an alternative purpose for your diode arrays -- involving either communications or adaptive measurement -- is going to be a Completely Good Defense for having them. The ideal thing is to arrange an IR detector and circuit (out of one of those laser tape measures from Home Depot, if stingy or not tech literate) and rig it up to the plate to use as a 'parking distance control'; a better cover story for your modulated light would be to provide some sort of Distronic-like differential distance indicator for your dashboard, better yet get an input to the cruise control (that, for instance, simulates a brake application to disengage cruise if you get 'too close' to what's ahead of you, but not too close to something in an adjacent lane... an intelligent officer will figure out the problems with this (such as eliminating 'false disengage' on even subtle curves) BUT I suspect "proving" what you were "doing" would become much simpler in the courtroom, if you have to go that far... I suppose I should mention that the alternative technique -- the analogue of retuning some big-ass magnetron to the appropriate frequency and running it to an even bigger-ass Yagi on a universal servo mount -- is not a particularly good idea, particularly if some bright prosecutor starts invoking Dangerous-To-Vision Laser Radiation (oooh, don¹t'cha love how that word sounds to a judge or jury?) as a public danger. And I do suspect that day will be coming... ------------------------------ Date: Tue, 12 Dec 2006 13:11:23 -0500 From: "Dennis Liu" <[EMAIL PROTECTED]> To: <[email protected]> Subject: Re: Tom Swift laser doohickey Message-ID: <[EMAIL PROTECTED]> Awesome info. Thanks for taking the time. Looks like I'm back to the Blinder-group-discount-purchase strategy! Vty, --Dennis -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Robert M. Ellsworth Sent: Tuesday, December 12, 2006 1:06 PM To: [email protected] Subject: Re: [UUC] Tom Swift laser doohickey Advance warning of laser via backscatter, etc. is probably a good idea always. And slowing down (using proper braking technique and attention to surrounding traffic, of course) is almost ALWAYS an appropriate response to 904nm illumination in uncertain circumstances... I could argue it's an appropriate response in ANY uncertain circumstances... Blinders around the license plate frame make the 'most' sense if you're going to use them, as that's, from my memory, where most officers are trained to aim in order to avoid issues with improper targeting. The translucent 'veil' is material that tries to do two things: scatter the light to reduce return-path intensity, and absorb light of the wavelengths used in lidar (usually in the 904nm range, historically, but I'd easily expect polyspectral devices "soon" if not already...) Note that if you wax the stuff, it stops doing its jobs almost instantly -- I would treat it as if it were 'flat black finish' if applying any detailing potions ;-} Any even half-*ssed lidar designer is going to be able to adjust the illumination sensitivity of his detector over a fairly wide range -- and modulate the power of his emitter (through variable filters if not directly at the diodes) so that the SNR of the calibrated pulses climbs up out of the "IR background". That clearly implies that you have to MODULATE the 904nm diodes in the same way that... shall we say, 'certain people' back in the day knew how to modulate X-band frequency so that it toggled the 'fastest return' logic on artificial-stupidity radar guns to some impossible speed range. (Note: NOT 'limits of display', or whatever, just enough that if the officer is dumb enough to be greedy and cite the 'actual' speed, you can prove him a liar, and if he tries to derate it, make him prove it... Remember that a laser radar isn't a SPEED measuring device using Doppler shift, it's a sequential-distance-measuring device that is dependent on a timing function to derive speed. This is why the sort of fast-braking-to-throw-off-lockup technique that can work with radar doesn't work with lidar -- two distance readings is enough to get you a speed, five is enough to give you the 4x verification dreaded by defense attorneys. So what an 'advanced' Tom Swift blinder modulator will do is send appropriately shifted pulse information *at high brightness* THAT VARIES WITH TIME AND BRAKING EFFORT right from the instant the 904nm light is detected. (Useful, of course, if you can pick up the pulse frequency the device uses and jam on that riff, but as noted by the time you decode the pulsetrain from a strong event, the device has already derived your speed...) You have at least two flavors of response: make it look like you're covering far less distance per pulse, or make it look like you're accelerating wildly fast (probably a sign to the lidar's internal logic that it's heterodyning two 'equal' returns). Personally, I'd do a little homework aka industrial espionage to see if there are 'consistent' pulsetrain timings in use for given makes of guns, and build my emitter driver base rate accordingly... Oh yes: look at the detection cone an officer would be using, and spec your divergence accordingly. As a first estimate, use the angle where cosine error for the sequential distance measurement would start to show significant speed error... and consider that a reasonable place to shoot lidar is going to be overpasses and so forth where the divergence is VERTICAL, remembering that cosine error in lidar UNDERSTATES your true speed (in a manner that is easily mathematically correctable from video or even derived geometry at trial time...) If, and I emphasize if, I were thinking of building such a thing, I would use several different cones of divergence, and perhaps rig the sets with selective switching (so you had the option of activating just the ones corresponding to an illumination source, and not false everything in scatter LOS from dust particles in the atmosphere or whatever ;-} Remember, gentlemen, the correct answer is not overkill, it's modulation; "Everything in modulation", to perhaps paraphrase Aristotle... this may also prove an advantage, albeit transitory, when the modern analogues to the Spectre III start looking around for high-intensity 904nm where it shouldn't be as I fully expect will soon be the case. Interesting little point, perhaps: Having an alternative purpose for your diode arrays -- involving either communications or adaptive measurement -- is going to be a Completely Good Defense for having them. The ideal thing is to arrange an IR detector and circuit (out of one of those laser tape measures from Home Depot, if stingy or not tech literate) and rig it up to the plate to use as a 'parking distance control'; a better cover story for your modulated light would be to provide some sort of Distronic-like differential distance indicator for your dashboard, better yet get an input to the cruise control (that, for instance, simulates a brake application to disengage cruise if you get 'too close' to what's ahead of you, but not too close to something in an adjacent lane... an intelligent officer will figure out the problems with this (such as eliminating 'false disengage' on even subtle curves) BUT I suspect "proving" what you were "doing" would become much simpler in the courtroom, if you have to go that far... I suppose I should mention that the alternative technique -- the analogue of retuning some big-ass magnetron to the appropriate frequency and running it to an even bigger-ass Yagi on a universal servo mount -- is not a particularly good idea, particularly if some bright prosecutor starts invoking Dangerous-To-Vision Laser Radiation (oooh, don¹t'cha love how that word sounds to a judge or jury?) as a public danger. And I do suspect that day will be coming... Search the ARCHIVES:http://www.mail-archive.com/[email protected] __________________________________________________________________________ In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA. UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate Short Shifter - accept no substitutes! 908-874-9092 . http://www.uucmotorwerks.com ------------------------------ End of [bmwuucdigest] digest(9 messages) **********
