I need a radar detector

Discussion in 'General Electronics Chat' started by Mans, Apr 2, 2016.

  1. Mans

    Thread Starter New Member

    Oct 1, 2012
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    I need a radar detector scheme that detect the signals of radar systems that have been installed beside the roads to specify speed limit of cars. The circuit must be able to detect the radar signals before it can lock on the car and specify its speed and alert me with a beep.
    I want to use this circuit to notify me, when I am approaching a speed radar so that I can reduce my speed before pay a fine.

    Of course I don't want use is as an illegal device, because I usually don't drive fast, but I am a forgetful person and sometimes don't look at the speed signs or don't remember where the speed radars have been installed!
     
  2. Dr.killjoy

    Well-Known Member

    Apr 28, 2013
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    Valentine1 radar system ...
     
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  3. #12

    Expert

    Nov 30, 2010
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    My 10 year old radar detector mostly finds church, hospital, and drugstore door openers.:( Buy a modern radar detector. Most of what was used 10 years ago is now irrelevant. If you're really serious, there are radar detectors that get updates constantly as other motorists detect speed traps and their detector reports them. They also know about door openers and learn to ignore them.

    Personally, I haven't had a ticket or collision in over 40 years. You don't accomplish that without being a conservative driver. I don't have a radar detector so I can drive badly and get away with it. I have one for those rare occasions when I'm not paying attention and need to be reminded, like when some cop has set up a trap on the down slope of a hill where everybody is using gravity assist to save gasoline.

    Back in 1973 I came down the west slope of the mountains into San Diego at 75 MPH...with the transmission in neutral.:eek:
    Great gas mileage, but I'm sure glad there were no cops nearby that day.:D
     
  4. wayneh

    Expert

    Sep 9, 2010
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    Agreed. A useful radar detector is not a DIY project. You need a design and a build using the latest state of the art, which these days includes lasers. Otherwise the cat will catch your mouse.
     
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  5. #12

    Expert

    Nov 30, 2010
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    When I started working with lasers in 1976, one of my first thoughts was, "How you gonna detect a beam the size of a nickle hitting you for less than a millisecond?"
    I can't see any way to defeat that except to receive an update from the cars ahead of you.
    As much as I don't want to Internet my life and location, I just can't see a way to beat a radar beam, so I drive good.:D
     
  6. Hypatia's Protege

    Distinguished Member

    Mar 1, 2015
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    @Mans

    Please be advised that, where prohibited, the penalty for 'being in the presence' of such a device while operating your vehicle upon public/streets highways is significantly greater than a speeding citation:eek:...

    With helpful intent

    Best regards
    HP:)
     
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  7. #12

    Expert

    Nov 30, 2010
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    Yes, there are some states where it is illegal to be aware you are under surveillance.
     
  8. Wendy

    Moderator

    Mar 24, 2008
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    But in most states not.

    If you (the TS) are interested in DIY you will need to find out the radar frequencies in your area. You also need to be sure you are not going to get into deeper trouble having one. I remember a unit I had 40 years ago that used two Schottky diodes in a feed horn. The first diode was fed a square wave, if there were microwaves present the square wave would show up on the second diode. Primitive, but it worked.
     
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  9. Hypatia's Protege

    Distinguished Member

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    By the self same method you are able to observe an object illuminated by a 'visible laser' --- A rather simple matter actually --- though I must confess to no little dubiety as regards this thread!:eek::rolleyes:

    Best regards
    HP:)
     
  10. #12

    Expert

    Nov 30, 2010
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    So, you detect it. How much can you slow down before the light gets back to the radar speed gun?

    Meanwhile, expecting to see new laws making it illegal to be aware your car was photographed 3 times on the way to the grocery store.:D
     
  11. Hypatia's Protege

    Distinguished Member

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    In my observation (but not necessarily experience;)) -- such devices are not-uncommonly prohibited at the municipal/county/district levels -- A 'forgetful person' need merely set his/her vehicle's 'speed alerting level' for the speed limit and dispense with the 'agro' altogether!:D:D:D

    Best regards
    HP
     
  12. Hypatia's Protege

    Distinguished Member

    Mar 1, 2015
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    One may readily detect scatter (from other vehicles, objects even airborne particles) before your vehicle is targeted:)

    Best regards
    HP:cool:
     
  13. Hypatia's Protege

    Distinguished Member

    Mar 1, 2015
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    On that point (i.e. outrage at the egregious erosion of personal privacy) we are in 100% agreement!:):):)

    Best regards
    HP
     
    Last edited: Apr 2, 2016
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  14. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Just move to Pennsylvania. The state legislature has decided that the only cops smart enough to use Radar/Lidar speed sensing systems are state highway patrol (state police). All other cops get to use a stopwatch and lines painted on the highway. Just slow down when you see a white line across the road for no reason. also, you have to go about 20% faster than the posted speed to get caught, otherwise a judge may through out the case because of timing error.
     
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  15. #12

    Expert

    Nov 30, 2010
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    Do you think they sit there with their lasers running? They wait for a car that looks wrong and fire at it. The laser is off most of the time.
     
  16. Hypatia's Protege

    Distinguished Member

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    Granted, where traffic volume is rather low OR your vehicle is conspicuously exceeding the limit, you're gonna have problems:eek: --- That said - it's my guess LEOs prefer better (i.e. higher volume) 'hunting grounds':cool:

    Best regards
    HP

    PS -- If anybody asks me what the Cop's 'lucky stars' have to do with it -- I Just know I'm gonna break down and cry!:(;)
     
  17. #12

    Expert

    Nov 30, 2010
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    A bit of Googling leads me to the number: 12,000 road officers per state (on the average).
    With that many potential surveillance points, the only way to avoid getting milked with the rest of the herd is to drive safely. It isn't a panacea, but it works for me.
     
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  18. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    It is all a question of priorities. I budget 2 speeding tickets per year and enjoy myself until I hit my limit (most years don't even get one ticket). Why waste all that time driving to an amusement park and waiting in line for the rollercoaster when you can find empty roads with safe and fun sections that are free (if you don't get a ticket). One speeding ticket is in the range of one or two visits to an amusement park. Luckily, I have a great section of road on my way to work - so I go home for lunch in the summer so I can do it two extra times each day.
     
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  19. Hypatia's Protege

    Distinguished Member

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    The 'hitch' with that philosophy is to be found in the fact that the fines are least of it! --- 'Round here 'adverse marks' on one's DMV record greatly prejudice law enforcement as regards 'benefit of the doubt' in 'traffic matters'!:mad::rolleyes:

    As an aside -- Here's a bit of advice to the 'penny-wise' and any whom dislike paternalistic oversight -- do not purchase liability insurance!!! -- But, rather, establish 'financial responsibility' via a trust (or whatever arrangement is amenable to your state's DMV) :):):)

    Best regards
    HP:cool:
     
  20. #12

    Expert

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    Pssst...your elitism is showing. Most of us don't have $50,000 to show the State. If we did, there is a confiscatory law allowing the police to seize that money without any crime, suspicion, or charges, until you prove it isn't "drug" money. Google, "Policing for Profit".
     
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