Need help getting hold of a laser gun...
Discussion
gh0st said:
Change of plan, am going to buy a laser distance measureing thingy. they cost a fraction of the 2,500 price tag of an lti and work on the same frequency / principle.
What's this laser measuring thingy then and where can you get them from?
I'm interested in getting my hands on something to do some testing
jjustin said:
Change of plan, am going to buy a laser distance measureing thingy. they cost a fraction of the 2,500 price tag of an lti and work on the same frequency / principle.
What's this laser measuring thingy then and where can you get them from?
I'm interested in getting my hands on something to do some testing
Focus DIY sell them for less than 50 squid i believe.
jjustin said:
Change of plan, am going to buy a laser distance measureing thingy. they cost a fraction of the 2,500 price tag of an lti and work on the same frequency / principle.
What's this laser measuring thingy then and where can you get them from?
I'm interested in getting my hands on something to do some testing
Up to 27m
Up to 200m
gh0st said:
Or if you spend a bit more you can get them that measure up to 600m away, the diy ones only do 50 - 150m (which is good enough for a basic "is it working"test i would have thought0)
Is a laser pointer such as those used at presentations (and also by morons to blind bus drivers) of any use.
Dunno the frequency but they would be much cheaper.
hello chaps,
CPC (Combined Precision Components) do a laser gun.
Sorry, it's a K-band radar device.
www.bushnell.com/support/faq_speed.html
If you're still intersted,
item number - CP03213
price £211.27 (+VAT)
phone order
08701-20 25 30 (uk
can spot anything from a tennis ball upwards,
can measure cars from 6 - 200MPH 1300 feet away.
looks like fun anyway.
CPC (Combined Precision Components) do a laser gun.
Sorry, it's a K-band radar device.
www.bushnell.com/support/faq_speed.html
If you're still intersted,
item number - CP03213
price £211.27 (+VAT)
phone order
08701-20 25 30 (uk
can spot anything from a tennis ball upwards,
can measure cars from 6 - 200MPH 1300 feet away.
looks like fun anyway.
laser pointers also aren't any good.
firstly, they are the wrong frequency ie approx 610nm as apposed to 905nm (610 is visible red light, 905 is invisible infra red light)
Like TV remote controls, the laser is both pulsed and modulated. Not sure what the modulation frequency is, but as a guide TV remotes are about 34 kHz. If Tv remotes simply flashed without modulation, you would have to hold the remote about 1 inch from the telly to get it to work.
LTI2020 speed guns are much the same, there isn't that much reflected light really from a number plate, and a modulated signal is much MUCH easier to pick up, especially at distance.
From my science background, there is infact quite a simple way to defeat laser guns. A small rotating convex mirror, or better still, several of them mounted in your lamp units. They are invisible, run all the time, and basically act like a 'mini infra red lighthouse' when a LTI is fired at them.
The LTI fires 44 pulses, and must recieve 30 coherent ones back from the object, on which it performs a 'least squares' algorithm.
spinning mirrors completely f****s this up. Error 2.
Error 2 Error 2.
If anyone wants one, I can probably build one for you to try.
science, don't you just love it!
firstly, they are the wrong frequency ie approx 610nm as apposed to 905nm (610 is visible red light, 905 is invisible infra red light)
Like TV remote controls, the laser is both pulsed and modulated. Not sure what the modulation frequency is, but as a guide TV remotes are about 34 kHz. If Tv remotes simply flashed without modulation, you would have to hold the remote about 1 inch from the telly to get it to work.
LTI2020 speed guns are much the same, there isn't that much reflected light really from a number plate, and a modulated signal is much MUCH easier to pick up, especially at distance.
From my science background, there is infact quite a simple way to defeat laser guns. A small rotating convex mirror, or better still, several of them mounted in your lamp units. They are invisible, run all the time, and basically act like a 'mini infra red lighthouse' when a LTI is fired at them.
The LTI fires 44 pulses, and must recieve 30 coherent ones back from the object, on which it performs a 'least squares' algorithm.
spinning mirrors completely f****s this up. Error 2.
Error 2 Error 2.
If anyone wants one, I can probably build one for you to try.
science, don't you just love it!
bryan35 said:
LTI2020 speed guns are much the same, there isn't that much reflected light really from a number plate, and a modulated signal is much MUCH easier to pick up, especially at distance.
From my science background, there is infact quite a simple way to defeat laser guns. A small rotating convex mirror, or better still, several of them mounted in your lamp units. They are invisible, run all the time, and basically act like a 'mini infra red lighthouse' when a LTI is fired at them.
The LTI fires 44 pulses, and must recieve 30 coherent ones back from the object, on which it performs a 'least squares' algorithm.
spinning mirrors completely f****s this up. Error 2.
Error 2 Error 2.
If anyone wants one, I can probably build one for you to try.
science, don't you just love it!
Now that I am interested in...... Purely from a scientific point of view of course...
Oh - and I can get it tested
>> Edited by NugentS on Friday 12th March 14:26
gh0st said:
He sent me a mail the other day saying that he doesnt do it anymore. Think he was getting busy with job and stuff so I wish him all the best 
Closest in Burton-on-trent which is miles away
Richard (the guy from Reading) is getting me a phone number of some chap in or around Oxford who is starting up the process. I will advise when I know more.
NugentS said:
He sent me a mail the other day saying that he doesnt do it anymore. Think he was getting busy with job and stuff so I wish him all the best
Closest in Burton-on-trent which is miles away
Richard (the guy from Reading) is getting me a phone number of some chap in or around Oxford who is starting up the process. I will advise when I know more.
Please.
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