john@anasaz.UUCP (John Moore) (02/10/88)
Here in Paradise Valley, Arizona, we have the dubious distinction of being the only place in the US where speeding tickets are given by mail after an automatic device snaps your picture and speed! About 10 days after the alleged offense, you get a speeding ticket in the mail. I find this pretty offensive, since I can't remember everywhere I go and how fast 10 days later. It has raised a lot of controversy (not to mention money for the town) since it has been installed, but so far has not been beaten in court. Today, I spotted this beast. I drove by and noticed that my radar detector didn't respond to it. The person running the device said that it operates on Ka band (34 gHz). Most radar detectors only operate on X (10 gHz) and Ku (24 gHz) bands. Also, he said that it only runs 1/2 milliwatt of power, making it detectable for about 1 second if you can receive Ka band. Finally, it will in the future use a laser, making it totally undetectable with microwave radar detectors. So.... If this thing continues to hold up in court, you could be next! Big brother is watching and taking your picture. Good Luck! P.S. It hasn't got me yet (I hope)! I don't speed in PV anyhow. -- John Moore (NJ7E) hao!noao!mcdsun!nud!anasaz!john (602) 870-3330 (day or evening) The opinions expressed here are obviously not mine, so they must be someone else's.
kevinr@tandem.UUCP (Kevin J. Rowett) (02/11/88)
In article <602@anasaz.UUCP>, john@anasaz.UUCP (John Moore) writes: > Here in Paradise Valley, Arizona, we have the dubious distinction of > being the only place in the US where speeding tickets are given by > mail after an automatic device snaps your picture and speed! > > that it operates on Ka band (34 gHz). Most radar detectors only Quite correct. > > So.... If this thing continues to hold up in court, you could be It has not held up much in CA! Speed Capital of the West. The CHP has had a hard time prosecuting the tickets in Northern CA. Basically, the evidence submitted is circumstantial. A quick fix is to install a slave strobe under your hood. When the ROBOCOP flashes, you flash! If your wattage is high enough, and your circuits fast enough, the picture won't be quite as good. Kevin Rowett .....ihnp4!ptsfa!pacbell!tandem N6RCE
robert@sri-spam.istc.sri.com (Robert Allen) (02/11/88)
In article <602@anasaz.UUCP> john@tower.UUCP (John Moore) writes:
+Here in Paradise Valley, Arizona, we have the dubious distinction of
+being the only place in the US where speeding tickets are given by
+mail after an automatic device snaps your picture and speed! About 10
+days after the alleged offense, you get a speeding ticket in the mail.
+I find this pretty offensive, since I can't remember everywhere I go
+and how fast 10 days later. It has raised a lot of controversy (not
+to mention money for the town) since it has been installed, but so
+far has not been beaten in court.
+
+Today, I spotted this beast. I drove by and noticed that my radar
+detector didn't respond to it. The person running the device said
+that it operates on Ka band (34 gHz). Most radar detectors only
+operate on X (10 gHz) and Ku (24 gHz) bands. Also, he said that it
+only runs 1/2 milliwatt of power, making it detectable for about
+1 second if you can receive Ka band. Finally, it will in the future
+use a laser, making it totally undetectable with microwave radar
+detectors.
Lasers huh? Well, there are ways to fight this. Blinding
the sensor with another stationary laser is one way, emitting
a laser when pulsed would be another would be difficult, but
maybe possible with a wide spread laser. However, I think the
best solution would be the use of a laser targeting system
on a large caliber long range weapons, such as a .300 Winchester
magnum. That should tend to inhibit Big Brother....
--
---------------------------------------------------------
Robert Allen, robert@spam.istc.sri.com
415-859-2143 (work phone, days)
---------------------------------------------------------welty@sunbarney.steinmetz (richard welty) (02/11/88)
In article <602@anasaz.UUCP> john@tower.UUCP (John Moore) writes: > about the new automagic ticket generators ... That sounds pretty accurate, given the reporting I've heard so far. I have heard one report that some civic minded souls have discovered that the ticket machine can be dealt with easily with a can of spray paint. I find this amusing, although I'd never actually recommend destruction of public property ... Richard Welty Phone H: 518-237-6307 W: 518-387-6346 {rochester,philabs,uunet}!steinmetz!welty welty@ge-crd.ARPA ``join the auto-sports mailing list -- it's easy and it's fun''
todd@uop.edu (Dr. Nethack) (02/11/88)
You would be amazed what a good rifle could do to that device.
;-)
---
uop!todd@uunet.uu.net
cogent!uop!todd@lll-winken.arpa
{backbone}!ucbvax!ucdavis!uop!todd jbn@glacier.STANFORD.EDU (John B. Nagle) (02/11/88)
Gadgets like this, although rare in the US, have been around for
years in Germany and Japan. But the radar/lidar approach really ought
to be replaced with a motion vision system which matched the images
from frame to frame and measured speed in that way. The major problem
is that television resolution isn't good enough to read a licence plate
given a field of view that covers an entire road. But once HDTV cameras
become generally available, this problem should go away. Even without
HDTV technology, it may be possible to make this work, although it will
probably take one camera per lane.
The major advantage of the video approach is that misidentification of the
vehicle can be much reduced, if not eliminated. With a videotape as a
check, there's an objective but human-checkable record to be examined in
court when necessary. This should make it a lot harder to be
falsely identified as the speeding car, while making it much easier to
get convictions in court.
Digesting the data at TV rates is hard, but not impossible.
Signal processing chips that can convolve images in real-time are starting
to become widely available. (Any DSP5600 users out there, by the way?)
Note that the only exposed component of the system is the camera, and
cameras are not only cheap, but tiny. (Pulnix has some very nice
cameras about 1" x 1" x4"; these are becoming popular with the robotics
people, especially when you want a camera near the end of an arm.)
There could be a nice product opportunity here for someone.
John Naglejohn@anasaz.UUCP (02/11/88)
In article <342@tandem.UUCP> kevinr@tandem.UUCP (Kevin J. Rowett) writes: >In article <602@anasaz.UUCP>, john@anasaz.UUCP (John Moore) writes: >> Here in Paradise Valley, Arizona, we have the dubious distinction of >> being the only place in the US where speeding tickets are given by >> mail after an automatic device snaps your picture and speed! >A quick fix is to install a slave strobe under your hood. When >the ROBOCOP flashes, you flash! If your wattage is high enough, >and your circuits fast enough, the picture won't be quite as >good. Clever idea! Unfortunately, this machine is accompanied by both a technician and a policeman, and it might result in one being chased and then charged with something nasty like obstruction of justice (anyone know if they can do this?). How about a near infrared emitter which will fog the film but be invisible to the operators? I don't know enough about the spectral response of the film, but there might be something that would work. -- John Moore (NJ7E) hao!noao!mcdsun!nud!anasaz!john (602) 870-3330 (day or evening) The opinions expressed here are obviously not mine, so they must be someone else's.
gwu@clyde.ATT.COM (George Wu) (02/11/88)
In article <602@anasaz.UUCP> john@tower.UUCP (John Moore) writes: >Today, I spotted this beast. I drove by and noticed that my radar >detector didn't respond to it. The person running the device said >that it operates on Ka band (34 gHz). Most radar detectors only >operate on X (10 gHz) and Ku (24 gHz) bands. Also, he said that it >only runs 1/2 milliwatt of power, making it detectable for about >1 second if you can receive Ka band. Finally, it will in the future >use a laser, making it totally undetectable with microwave radar >detectors. First off, unless you really think any followups have any bearing on sci.electronics, please remove it from the groups. Anyways, the latest ad for BEL detectors claims to detect all Ka as well as X and K (Ku) bands. Of course, at 0.5 mw of power, it may very well be hard to detect. As for the laser, does anyone have any ideas on commercializing stealth technology? George J Wu rutgers!clyde!gwu
karn@thumper.bellcore.com (Phil R. Karn) (02/11/88)
> ... the ticket machine can be dealt with easily with a can of spray > paint. Spray paint? Rifle bullets? Nah...too brute-force. Assuming that the radar works on the conventional CW Doppler principle, there is a much more elegant way. Just set up a small electric fan with metal blades in front of the device. If the blades are properly shaped (or re-shaped) and the fan turns at the right speed, the radar unit should be fooled into thinking it's seeing a speeder. Just leave the unit on long enough for the ticket machine to expend all of its film. Don't stand in front of the camera while you're doing this... Phil
ron@topaz.rutgers.edu (Ron Natalie) (02/12/88)
Gee around here I know a few people that would love to have such a device for their private collections. Seems to me that they had better be welded down pretty well. -Ron
todd@uop.edu (Dr. Nethack) (02/12/88)
or just take off your front license plate... keep it in the trunk with a lame excuse to a cop that you had intended to go get some new screws to mount it.. you can speed, they can take your picture, but so what??
madd@bu-cs.BU.EDU (Jim Frost) (02/12/88)
In article <610@anasaz.UUCP> john@anasaz.UUCP (John Moore) writes: >In article <342@tandem.UUCP> kevinr@tandem.UUCP (Kevin J. Rowett) writes: >>In article <602@anasaz.UUCP>, john@anasaz.UUCP (John Moore) writes: >>> [...] speeding tickets are given by >>> mail after an automatic device snaps your picture and speed! > >>[...] install a slave strobe under your hood. When >>the ROBOCOP flashes, you flash! > >Unfortunately, this machine is accompanied by both >a technician and a policeman [...] >How about a near infrared emitter which will fog the film >but be invisible to the operators? Why not go all out and make an X-ray projector? If you manage to make it tight-beam, you'll be able to completely blacken the film (probably even the whole roll, to the delight of everyone else that day). Of course, X-rays are sufficiently dangerous that you might hurt the operators if you go by them very often. Come to think of it, a CO2 laser of sufficient power could do some pretty good damage, too, and is also invisible. But now we're getting into SDI-style defenses... jim frost madd@bu-it.bu.edu
matt@shorty.CS.WISC.EDU (Mad Matt Schaefer) (02/12/88)
In article <602@anasaz.UUCP> john@tower.UUCP (John Moore) writes: >Here in Paradise Valley, Arizona, we have the dubious distinction of >being the only place in the US where speeding tickets are given by >mail after an automatic device snaps your picture and speed! About 10 I've heard of this system in Europe (Germany?) and somebody told me that it became unpopular with government officials and other important people because the ticket and picture came in the mail while the guy was at work and his wife opened it and saw the picture of the car, plate, speed, husband, and *the other woman* in the car with him. I thought, "this guy is not gonna get the welcome he is expecting when he gets home." Mad Matt Schaefer ...!{harvard,ihnp4,rutgers,ucbvax}!uwvax!matt UW-Madison Computer Sciences Laboratory matt@cs.wisc.edu
mrapple@uop.edu (Nick Sayer) (02/13/88)
The big problem is that Robocop won't know who is DRIVING the car. In this country, moving violations go against the record of the driver, not the owner of the car. So you can say, "Gee, Judge Wapner, I was in a bar in Cincinati at that time. I don't know who was driving my car..." ---------------------------------------------------------------------- Nick Sayer | Packet Radio: N6QQQ @ WA6RDH | CMS: SYSOP@STOKTON%STOCKTON uucp: ...!sdcsvax!ucbvax!ucdavis!uop!mrapple | Fido: 161/31 Disclaimer: You didn't REALLY believe that, did you? cat flames > /dev/null
todd@uop.edu (Dr. Nethack) (02/13/88)
In article <1070@uop.edu>, mrapple@uop.edu (Nick Sayer) writes: > > The big problem is that Robocop won't know who is DRIVING the car. Yeah, the picture was your twin brother huh? > In this country, moving violations go against the record of the > driver, not the owner of the car. So you can say, "Gee, Judge Wapner, > I was in a bar in Cincinati at that time. I don't know who was driving > my car..." Must be the *other* nick sayer in that picture! > Nick Sayer | Packet Head: N6QQQ @ WA6QRM| CMS: SYSOP@STOKTON%STOCKTON > uucp: ...!sdcsvax!ucbvax!ucdavis!uop!mrapple | Fido: 161/31 > Disclaimer: You didn't REALLY believe that, did you? Nope! > nick's head = /dev/null
reese@eeg.UUCP (Reese E. Faucette) (02/13/88)
In article <11407@sri-spam.istc.sri.com>, robert@sri-spam.istc.sri.com (Robert Allen) writes: > ... However, I think the > best solution would be the use of a laser targeting system > on a large caliber long range weapons, such as a .300 Winchester > magnum. That should tend to inhibit Big Brother.... good thing b.b. doesn't think the same way! -- Reese E. Faucette, EEG Systems Laboratory 1855 Folsom St, San Francisco, Ca 94103 (415) 621-8343 {ihnp4,lll-crg,sun,qantel,pyramid}!ptsfa!eeg!reese -or- reese@sim.berkeley.edu
welty@sunbarney.steinmetz (richard welty) (02/14/88)
In article <1070@uop.edu> mrapple@uop.edu (Nick Sayer) writes: >The big problem is that Robocop won't know who is DRIVING the car. >In this country, moving violations go against the record of the >driver, not the owner of the car. So you can say, "Gee, Judge Wapner, >I was in a bar in Cincinati at that time. I don't know who was driving >my car..." This proves to be alterable via local statute. Communities that are trying out the robocop have altered their laws so that they may charge the owner if said owner refuses to identify the driver at the time of the infraction. I wonder if the owner gets any points from this ... Richard Welty Phone H: 518-237-6307 W: 518-387-6346 {rochester,philabs,uunet}!steinmetz!welty welty@ge-crd.ARPA ``join the auto-sports mailing list -- it's easy and it's fun''
sampson@killer.UUCP (Steve Sampson) (02/14/88)
The radars are not left unattended (illegal in usa). The version I saw was in the back of a Blazer. Is anyone else working on a HARM missle for this thing... I understand the collection rate is almost 100% before trial. The pictures are excellent!
maa@ssc-vax.UUCP (Mark A Allyn) (02/15/88)
If they use lasers for speed detections, they would have to meet very VERY stringent laser safety standards. Aiming a laser at a car with a driver in it could cause BLINDNESS to the poor driver if VERY stringent controls are not adhered to. Laser light is very dangerous if it is aimed directly into someone's eyes. No, I dont think this will happen. Also on the subject of automated speeding detectors, you guys have forgotten something very important. Vandalism/sabotage. Remember, these things are unmanned and at the mercy of those who hate them and what they represent. A piece of duct tape over the camera lense arpiture would do the job temporily or better still, a heavy pick up with a snowplow on it . . . . .
henry@utzoo.uucp (Henry Spencer) (02/16/88)
> ... it might result in one > being chased and then charged with something nasty like > obstruction of justice (anyone know if they can do this?). Interfering with a police officer in the performance of his duties is usually a serious offence. Almost anything you do to interfere with a police radar setup would probably qualify, if detected. > How about a near infrared emitter which will fog the film > but be invisible to the operators? ... Might work. Remember that "near infrared" is not entirely invisible if it's bright; the eye's sensitivity tails off in the IR, but it doesn't go immediately to zero. Some of the near-IR fiber-optic wavelengths are visible, dimly, in a dark room. Your IR flash is going to have to be pretty bright if it's going to mess up the picture seriously. It might be better to try for localized effects in crucial areas like the license plate. Near-IR markings, brightly lit in the near IR, might make it impossible to read the number. I don't know offhand whether suitable marking materials are available, though. -- Those who do not understand Unix are | Henry Spencer @ U of Toronto Zoology condemned to reinvent it, poorly. | {allegra,ihnp4,decvax,utai}!utzoo!henry
henry@utzoo.uucp (Henry Spencer) (02/16/88)
> This proves to be alterable via local statute. Communities that are > trying out the robocop have altered their laws so that they may charge > the owner if said owner refuses to identify the driver at the time of > the infraction. I wonder if the owner gets any points from this ... More significant, I wonder if it is legal, given the constitutional rules about innocent-until-proven-guilty and self-incrimination. Getting it struck down could be lengthy and expensive, mind you. -- Those who do not understand Unix are | Henry Spencer @ U of Toronto Zoology condemned to reinvent it, poorly. | {allegra,ihnp4,decvax,utai}!utzoo!henry
moto@cad.Berkeley.EDU (EDIF Committee) (02/16/88)
Not only are they trying robo-cops, there is a new law which reclasifies most driving offenses as "civil" - what that means is that you are guilty unless you can prove innocence! The "legalese" is that the officer is unbiased, and his word is equal to yours, unless you have something to back you up. The standard of guilt is 50/50! BB is alive and well in AZ! Mike .
todd@uop.edu (Dr. Nethack) (02/17/88)
What about building an awacs-esque array that will pick up the
police radio's local oscillator (air ground and radar)??
This is *sci* electronics, maybe we could discuss the necessary theory?
-----------------------------------------------------------------------
+ uop!todd@uunet.uu.net +
+ cogent!uop!todd@lll-winken.arpa +
+ {backbone}!ucbvax!ucdavis!uop!todd +
-----------------------------------------------------------------------
alias /dev/null postmaster@nmtvax
;-) bilbo@pnet02.cts.com (Bill Daggett) (02/17/88)
Gee, you mean traffic may have to start slowing down or we risk getting a
speeding ticket in the mail returning home from work or play? And when
statistics start showing a drop in fatalities? Boy, it's going to be tuff.
Like smokers giving up their habit. Do we all have a degree of "death wish"?
Isn't it exciting to read how to try and beat the law? No, not really - but
this is just my personal insight and feeling. Thanks for letting me share it
with you.
Bill
UUCP: {ihnp4!scgvaxd!cadovax rutgers!marque}!gryphon!pnet02!bilbo
INET: bilbo@pnet02.cts.comjohn@anasaz.UUCP (John Moore) (02/18/88)
In article <982@ssc-bee.ssc-vax.UUCP> maa@ssc-vax.UUCP (Mark A Allyn) writes: > >If they use lasers for speed detections, they would have to meet >very VERY stringent laser safety standards. Aiming a laser at Lasers are already used in some places. >things are unmanned and at the mercy of those who hate them and what they Once again: The one around here is manned by an armed policeman! I suspect that any usage in the US they will be manned or otherwise well protected, given out penchant for vandalizing things that we like, much less things that we dislike! -- John Moore (NJ7E) hao!noao!mcdsun!nud!anasaz!john (602) 870-3330 (day or evening) The opinions expressed here are obviously not mine, so they must be someone else's.
welty@sunbarney.steinmetz (richard welty) (02/19/88)
In article <2588@gryphon.CTS.COM> bilbo@pnet02.cts.com (Bill Daggett) writes:
... various comments of Bill's omitted ...
-- I'd like to dispute one of them, but this is massively crossposted, so
instead I'll point out that we (all of us, in all three newsgroups here)
have been doing a terrible job of editing the newsgroups: line. The
relevance of this to sci.electronics is essentially non-existant, and
the relevance to rec.ham-radio is not all that perceptible.
What amazes me (not being a reader of sci.electronics or rec.ham-radio)
is that we rec.autos types haven't yet inspired massive flaming of the
usual sort. sci.electronics and rec.ham-radio must be very pleasant
places by net.standards.
Seriously, please check the newsgroups line.
Enough for now -- I have to go post a light-bulb joke to rec.arts.woebegon
Richard Welty Phone H: 518-237-6307 W: 518-387-6346
{rochester,philabs,uunet}!steinmetz!welty
welty@ge-crd.ARPA
``join the auto-sports mailing list -- it's easy and it's fun''john@anasaz.UUCP (John Moore) (02/20/88)
In article <9597@steinmetz.steinmetz.UUCP> welty@sunbarney.UUCP (richard welty) writes: >have been doing a terrible job of editing the newsgroups: line. The >relevance of this to sci.electronics is essentially non-existant, and >the relevance to rec.ham-radio is not all that perceptible. As the original poster of this Robocop Spotted article, let me point out that I posted to three newsgroups for a reason: The interest in rec.autos is obvious. rec.ham-radio has many readers interested in the technology involved. rec.electronics also has readers interested in the technology who may not read rec.ham-radio. Once side threads develop, editing the newsgroups line makes a lot of sense. -- John Moore (NJ7E) hao!noao!mcdsun!nud!anasaz!john (602) 870-3330 (day or evening) The opinions expressed here are obviously not mine, so they must be someone else's.
snoopy@doghouse.gwd.tek.com (Snoopy) (02/20/88)
In article <602@anasaz.UUCP> john@tower.UUCP (John Moore) writes: > Finally, it will in the future > use a laser, making it totally undetectable with microwave radar > detectors. I assume they won't care about zapping people in the eye with lasers anymore than they care about zapping them in the eye with microwaves. -sigh- Snoopy tektronix!doghouse.gwd!snoopy snoopy@doghouse.gwd.tek.com "And with multiple vapor-processors, it does 50 vapor-MIPS."
erict@flatline.UUCP (eric townsend) (02/20/88)
In article <21649@clyde.ATT.COM>, gwu@clyde.ATT.COM (George Wu) writes: > Anyways, the latest ad for BEL detectors claims to detect all Ka > as well as X and K (Ku) bands. Of course, at 0.5 mw of power, it may very > well be hard to detect. As for the laser, does anyone have any ideas on > commercializing stealth technology? > George J Wu > rutgers!clyde!gwu Well... It was explained to me that older corvettes are more immune from all radar because of their angled radiator design... Dunno If I want to believe this. Toyota, Japan has a test bed vehicle with just about any time of sensing navagational device you could want in a car. Why not have passive sensing devices that listen for nearby xmissions on police band? Maybe sensors on the front and rear doing a quick bit of ranging? Then assume that all cops are running radar.. Oh well, I suppose this doesn't belong on sci.electronics, does it... -- Just say NO to skate harassment. | Just another journalist with too much If I wish really hard, will IBM go away forever? | computing power.. Girls play with toys. Real women skate. -- Powell Peralta ad J. Eric Townsend ->uunet!nuchat!flatline!erict smail:511Parker#2,Hstn,Tx,77007
tga@eleazar.Dartmouth.EDU (Greg Ames) (02/22/88)
In article <9774@tekecs.TEK.COM> snoopy@doghouse.gwd.tek.com (Snoopy) writes: >In article <602@anasaz.UUCP> john@tower.UUCP (John Moore) writes: > >> Finally, it will in the future >> use a laser, making it totally undetectable with microwave radar >> detectors. > >I assume they won't care about zapping people in the eye with lasers >anymore than they care about zapping them in the eye with microwaves. Small problem with the logic here... Getting shot in the eye with laser radiation has been scientifically proven to cause retinal damage, even at fairly low doses. Microwaves are harmless, except at high doses (all they do to biological tissue is heat it, not cause cromosome damage) To put it in perspective, a microwave oven emits about 700 watts (or more) of power inside it. Radar guns are on the order of a few hundred milliwatts (or about .001 times the power of an oven) All that a cop's radar gun will do to you is heat your body tissue about .0000001 degrees. -Greg [-----------------------------------------------------------------------------] [ Greg Ames US Mail - HB 1362, Dartmouth College] [ E Mail - tga@eleazar.Dartmouth.EDU Hanover, NH 03755 ] [-----------------------------------------------------------------------------]
stevewa@upvax.UUCP (Steve Ward) (02/23/88)
>(...) All that a cop's radar gun will >do to you is heat your body tissue about .0000001 degrees. > -Greg Generally speaking, I'm sure that's true. HOWEVER, a friend of mine owns a radar gun (picked up at a police auction, he's a traffic reporter for a radio station, so he has a good use for it) and he found out the hard way that they can indeed be dangerous. He made the mistake of pointing it at his face when it was turned on (OK, he's not too bright :-) ), and burned his face pretty good from just a few seconds of exposure. I don't know how quickly the power of the microwaves decreases with distance (probably expotential) but it seems that with the longer amount of exposure it could be POTENTIALLY dangerous. Steve Ward stevewa@upvax.UUCP University of Portland !tektronix!upvax!stevewa
krc@cs.purdue.EDU (Kenny "RoboBrother" Crudup) (02/24/88)
In article <321@upvax.UUCP>, stevewa@upvax.UUCP (Steve Ward) writes: > Generally speaking, I'm sure that's true. HOWEVER, a friend of mine owns > a radar gun and he found out the hard way > that they can indeed be dangerous. He made the mistake of pointing it at > his face when it was turned on and burned > his face pretty good from just a few seconds of exposure. > Steve Ward stevewa@upvax.UUCP I can see it now, in some bass-ackwards town with a shithead sheriff and some poor slob with no money stopped doing 105. "You got two choices: You can pay the fine or smile inna this here DE-tek-tor for a coupla minutes. Heh Heh Heh." Or better yet- spot microwaving for those foods that don't need the *whole* oven! Keeps the hot-side hot, and the cold-side cold! (*This technology courtesy of the McDonalds corporation) -- Kenny "_R_o_b_o_B_r_o_t_h_e_r" Crudup krc@arthur.cs.purdue.edu Purdue University CS Dept. W. Lafayette, IN 47907 1-31-88. A great day for football, +1 317 494 7842 and Black Americans. Yo Dougie!
ssr@COS.COM (Dave Kucharczyk) (02/25/88)
In article <321@upvax.UUCP> stevewa@upvax.UUCP (Steve Ward) writes: >>(...) All that a cop's radar gun will >>do to you is heat your body tissue about .0000001 degrees. >> -Greg > >Generally speaking, I'm sure that's true. HOWEVER, a friend of mine owns >a radar gun (picked up at a police auction, he's a traffic reporter for a >radio station, so he has a good use for it) and he found out the hard way >that they can indeed be dangerous. He made the mistake of pointing it at >his face when it was turned on (OK, he's not too bright :-) ), and burned >his face pretty good from just a few seconds of exposure. I don't know >how quickly the power of the microwaves decreases with distance (probably >expotential) but it seems that with the longer amount of exposure it could >be POTENTIALLY dangerous. > As far as tissue "heating" goes radar guns are not anywhere near the right frequency for heating water (like a microwave oven) however if the field strength is high enough you can get RF burns just like from any other transmitter. The field strength changes as the reciprocal of the distance squared (1/d^2) from the source. However microwaves have enough penetration to get inside your skull and the effects of that can be rather interesting (the Russian's tried shooting microwaves through the windows at the US embassy in Moscow). They vary from "hearing" a constant buzz to nausea and general irratability. There's an old saying why Virginia state troopers act so funny sometimes (they used to position their radar guns in the back of the car pointing forward !)... ssr Usual discalaimer at employers request (The opinions stated here are all mine).
brian@ucsd.EDU (Brian Kantor) (02/25/88)
Just program your scanner to listen for the local oscillator frequency of the police radio. For example, if the police frequency is 158.97 MHz (as it is in my area), and the radio is a Motorola Micor, then the IF frequency is 11.7 MHz so the local oscillator will be at either 170.67 MHz or 147.27 MHz (i.e. the channel +/- the IF). Around here, it's 147.27, so I just leave my radio tuned to that frequency, and whenever I'm within a block or so of a police car, my scanner starts to sputter and belch from the very weak signal radiated by the police car's receiver. Only problem is that 147.27 is a popular ham radio frequency, so if some old farts are gassing about their ailments, I don't hear the PD. But you might be luckier. - Brian
muller@Alliant.COM (Jim Muller) (02/26/88)
In article <418@flatline.UUCP> erict@flatline.UUCP (eric townsend) writes: >Well... It was explained to me that older corvettes are more immune >from all radar because of their angled radiator design... Dunno >If I want to believe this. It is believable. Quite some years ago now, maybe >10, C&D did several tests of various detectors/cars/techniques, and one thing they discovered was that the Corvette and the Honda Civic were both poor radar reflectors. The reason for the Corvette being bad (good) is not especially because of its plastic body, since the plastic just passes the radar on to the next reflector in, and there are plenty of them (radiator, block, driver's face, bumper, anything else metal or water). In this case, though, the bumper (a big, flat slab of steel on some cars) was just a thin strip, angled sharply. The radiator was angled up, and it effectively shielded the block with its shadow. That a radiator would be a good radar reflector is quite understandable, since the wavelenghts are on the order of a few centimeters. Surface irregularities smaller than the wavelength tend to be "ignored". Thus a car radiator, with its few-millimeter spacing of metal conductors, looks just about like a mirror to radar.
ard@pdn.UUCP (Akash Deshpande) (02/27/88)
In article <321@upvax.UUCP>, stevewa@upvax.UUCP (Steve Ward) writes: > I don't know > how quickly the power of the microwaves decreases with distance (probably > expotential) ... > Steve Ward stevewa@upvax.UUCP Probably inverse square
Jinfu@cup.portal.com (02/28/88)
Erict@flatline.UUCP (eric townsend) writes: >Well... It was explained to me that older corvettes are more immune >from all radar because of their angled radiator design... Dunno >If I want to believe this. We all know that DoD invests tons of money in developing special materials for aircraft surface to reduce reflection of radar. I wonder if there will be some sort of spin-off product for civilian applicaion, such as low-reflection pain for cars. I hope I am not day dreaming. Jinfu Chen
aptr@ur-tut.UUCP (The Wumpus) (02/29/88)
In article <3541@cup.portal.com> Jinfu@cup.portal.com writes: >Erict@flatline.UUCP (eric townsend) writes: >>Well... It was explained to me that older corvettes are more immune >>from all radar because of their angled radiator design... Dunno >We all know that DoD invests tons of money in developing special >materials for aircraft surface to reduce reflection of radar. I wonder >if there will be some sort of spin-off product for civilian applicaion, >such as low-reflection pain for cars. I hope I am not day dreaming. I actually thought about how to make a car radar "invisible" a few months back. The trick is not to use any of the fancy fiber-glass or plastic panels, but to use thin metal, probably titanium or aluminum. Instead of trying to make the car so that it does not reflect any radar, make it so that it reflects the radar away from the source. The car would probably have a long slanting hood (approx 30%) and never have any part of the front perpendicular to the road. For added protection, it might be a good idea to put some radar absorbing foam behind the metal body panels to make sure any radar that gets past the panels is not reflected back to the source. The windshield should be impregnated or coated with some metal. Maybe the transparent aluminum that is being used by one of the big three for defrosting the window should be used. Of course, a radar detector mounted outside of the body is nessicary. The car is designed to be invisible from the front, affording the driver enough time to slow down to a legal speed before the more visible tail of the car can be clocked. Unfortunately, if you start thinking about what a car that reflects all the radar away from the source would look like, you come up with a car that could easily be pulled over because it looks too fast. "You may not be speeding, but who is going to beleive you weren't speeding in _this_ car?" -- The Wumpus UUCP: {cmcl2!decvax}!rochester!ur-tut!aptr BITNET: aptrccss@uorvm Internet: aptr@tut.cc.rochester.edu Disclaimer: "Who? When? Me? It was the Booze!" - M. Binkley
madd@bu-cs.BU.EDU (Jim Frost) (02/29/88)
In article <1056@ur-tut.UUCP> aptr@tut.cc.rochester.edu.UUCP (The Wumpus) writes: >>Erict@flatline.UUCP (eric townsend) writes: >>>Well... It was explained to me that older corvettes are more immune >>>from all radar because of their angled radiator design... > >I actually thought about how to make a car radar "invisible" a few >months back. The trick is not to use any of the fancy fiber-glass or >plastic panels, but to use thin metal, probably titanium or aluminum. >Instead of trying to make the car so that it does not reflect any >radar, make it so that it reflects the radar away from the source. [description of whole car design deleted] >Unfortunately, if you start thinking about what a car that reflects >all the radar away from the source would look like, you come up with a >car that could easily be pulled over because it looks too fast. "You >may not be speeding, but who is going to beleive you weren't speeding >in _this_ car?" Your description is quite good, but you don't have to build the entire car like this. As previously mentioned, the Corvette's design led to low radar image even though it had not been designed that way. You need only bounce the radar from items that would return a radar image of sufficient strength to be useful. Generally, this means the engine block. Why not put angled plates around the engine that would either reflect the radar up or down (or both)? Make the car body out of some non-radar-reflecting substance (such as plastic). The car itself would be invisible to the radar, and the big target (the engine) would be protected. Your car wouldn't even have to look "fast". jim frost madd@bu-it.bu.edu
carl@aoa.UUCP (Carl Witthoft) (03/02/88)
In article <2341@pdn.UUCP> ard@pdn.UUCP (Akash Deshpande) writes: >In article <321@upvax.UUCP>, stevewa@upvax.UUCP (Steve Ward) writes: >> I don't know >> how quickly the power of the microwaves decreases with distance (probably >> expotential) ... >> Steve Ward stevewa@upvax.UUCP > > Probably inverse square It's like any other E-M field: inverse square if point source, all sorts of interesting decay if not. -- Alix's Dad ( Carl Witthoft @ Adaptive Optics Associates) {ima,harvard}!bbn!aoa!carl 54 CambridgePark Drive, Cambridge,MA 02140 617-864-0201 "People unclear on the concept: 'Nah, I don't want to windsurf, I wanna do more C-programming.' "
mwwheatl@uokmax.UUCP (Mark W Wheatley) (03/02/88)
Concerning the automatic ticket/photo taking machines... While looking through a June 20, 1969 London Times (just to see what was up the day before the Moon shot) I founbd an article about such a device having been developed in Texas and just being brought over to Europe to see if anyone was interested. My point is this technology is not as new as some may think. My apologies is this point has been posted before as I am new to this newsgroup. Mark Wheatley mwwheatl@uokmax.UUCP [...ihnp4!occrsh!uokmax!mwwheatl]
mikef@wynalda.UUCP (Mike Faber) (03/05/88)
In article <3541@cup.portal.com>, Jinfu@cup.portal.com writes: > such as low-reflection pain for cars. I hope I am not day dreaming. ^^^^^^^^^^^^^^ ^^^^ I prefer my cars to deal with High-reflection pain, myself. It let's that paint job last longer. -- _ _ | This article contains no thought, so my employer (/ (/ _ _ _ _ | and sysop cannot share my opinions. (/) /\_(/_(/_/|_)_/ \_/ | Joe C Programmer (mikef@wynalda.uucp) work (| (| | Michael Faber (sleepy@wybbs.uucp) play