Radar detecter alternatives. Techie input needed

[Ixion]

*DISCLAIMER* Any police type persons reading this please note. The whole of this post is totally hypothetical. I, personally, would never dream of exceeding any speed limit. Nor would anyone else in this group. Purely a hypothetical exercise about what *other* people might do, none of whom are anything to do with this group. Or me. I never speed . Ever. Honest. So I would have no use for what I am talking about. Except as a purely intellectual exercise.

Now that we've got that out of the way.

As we all know, a good radar detecter is pretty much essential for anyone who might (unlike me) occassionally, purely inadvertantly, allow their speedometer to go round to figures that it ought not to (Not that mine ever does . I am renowned as the most nanaish rider around. Small children run out to point as I pootle past and cry "Look there goes nana". So none of this applies to me. Don't come looking for me)

But, with the new stalker and instant on and such like, radar detecters are having a hard time detecting in time to be of any use

Now, I'm sure that the radar detecter makers are working on this. But probably won't have any good answers in the short term

However (bear with me this is where it gets more interesting), it occurs to me that radar detectors may often actually be over kill.

In my case , if I were going to speed (WHICH I NEVER DO - see disclaimer above. Wouldn't ever dream of it) , but if I hypothetically were going to, it would be in a lonely-ish place, where there was not a lot of other traffic.And in such a place, all I want to know is that there is no Mr Plod within 5 km or so. If I know that Mr Plod is lurking anywhere near I will stick to the limit (AS I ALWAYS DO ANYWAY. Hypothetical, remember)

So , hypothetically, if I had some way of just knowing that there is a police car/bike in the area, that's all I need to know. I will assume he is using radar (not that it would worry me, you understand, on account of I never speed) .

The new radars are too hard to pick up in time. But a police car has a whole bunch of other radio stuff in it. All the comms stuff.

I know that scanners can pick that up. So, my question for you radio techie folk (I know there's a few of you on the group), is, could a scanner be modified so as to flash a light or something, if it detected activity on a known police band within say , 5 km. We know what the police frequencies are (I think). And it wouldn't really matter if they were scrambled, because all I want to know ( hypothetically) is that someone close by is using the police frequency , I don't care what they are saying (Not that i really want to know anyway, because I never speed. This is purely hypothetical. Hypothetical, that's what it is )

Or is there such a gadget existing already. Or have I totally got the wrong end of the (hypothetical) stick,and there is a insurmountable problem with my theory.

Of course such a warning device (which I have no need for and if I did have one it would be out of scientific interest only) would be no use in built up areas, where there are bound to be Plods within range. But that's OK because I think that anyone who speeds in built up areas is asking for it anyway. (Not that I would ever speed in any area at all, because as everyone knows I am the original nana, and never go fast at all )

Anyone want to comment on the idea of a general Plod detector ? (on a purely hypothetical basis of course, because no-one in this group would actually have any need for such a device)

Or offer meaningful technical insights ?

[zeRax]

weaker powered scanner as to only pick up radio thats close by? *starts thinking*, problem is will it show up if they arent talking on it, or could you transmit onto that channel and pick up anything thats recieved it in close proximity


argh, someone super start thinking ;D

[Quasievil]

wow thats a big read.
Now my answer, SASlex where is your techo arse

[Jeremy]

Sure it wouldn't be hard to find someone who was broadcasting at the police frequencies but it'd be much harder to pick up someone who was listening.

Also there's going to be on another problem. Once you reach those sorts of speeds you have to take into the account a quite severe doppler effect. And I'm not sure how isolated the police bands are, however if there's other stuff around them then it's going to be a real pain adjusting the frequency detection.

Theoretically it is possible to detect if someone is listening into a certain frequency but it's not an easy of a feat. It is entirely possible though. The Japanese did it during WW2 to pick up US forces.

This is going to cause a problem though, as trying to listen into people listening into a radio signal will also mean that you start to pick up people who are trying to do the same thing. Thus it's only useful when only a small number of people have these devices. Also the police would then start to put resonate blockers in their antenne like the US did, so it won't be useful for very long.

[ManDownUnder]

OR

... we sneak up to ye 'old Police Car/bike/mode of vehicular transport... and stick a teenie weenie transponder onto it...

It only has to do a sputnik and ping on a known frequency...

after that we can pick 'em up for ourselves. Course it would turn us into a bunch of perverts (perverting the course of justice) but then I believe a number of us... errmm... you... already are!

...?

[Ixion]

OR

... we sneak up to ye 'old Police Car/bike/mode of vehicular transport... and stick a teenie weenie transponder onto it...

It only has to do a sputnik and ping on a known frequency...

after that we can pick 'em up for ourselves. Course it would turn us into a bunch of perverts (perverting the course of justice) but then I believe a number of us... errmm... you... already are!

...?

Interesting thought. Given that it's really only a handful that we (oops, a hypothetical group of people, NOTHING TO DO WITH ANYONE HERE) have problems with.

Transponders is cheap. So it's just a matter of figuring out how to attach them. Not sure that it would be breaking any law. After all, none of us have any reason to avoid Mr Plod .

[Sniper]

Hypothetically speaking (of course) you could create a signal burst via the detector to pick up any police activity (if you did accidentaly speed) that could confirm the locality of police personall within a 5km radius.

This is possible if you know the band and also know how to send a signal burst (kind of like a ping for you who know computers) but being the law abiding person I am, I do not (hypothetically) have a way to do that.

[Blackbird]

Talk about dancing around the subject, haha

(Oh, good afternoon!)

I have a relatively cheap detector I bought from Trademe.com for $150 and this will pick up most police activity at up to 3 km. Probably even more importantly, it will pick up camera vans from several hundred metres. Looking at the whole thing pragmatically, police are no different from the rest of the human race (inclined to be lazy) and leave their detection systems on most of the time and the fact that they give other traffic ahead of you a burst usually gives the game away. Always a bit more of a risk when you're on your own.

Take the easiest approach rather than trying to develop something else (oh, that's right, you're in I.T) If you don't want to lay out a fortune, buy a Uniden LRD2000 Stalker. These are far better than the later models which were built to a component price to accomodate all the extra features.

[Ixion]

From one of the scanner maker's catalogues

The all-new BearTracker BCT8 is a significant upgrade over the 7 in many ways,foremost of which is the addition of Uniden's unmatched TrunkTracker III technology.
...
Additionally the scanner alerts you to the presence of many state police and
highway patrol cars in a 1-3 mile radius that are using mobile-extender radios
with its unique alert feature.

[Ixion]

..
I have a relatively cheap detector I bought from Trademe.com for $150 and this will pick up most police activity at up to 3 km. Probably even more importantly, it will pick up camera vans from several hundred metres. ..

Take the easiest approach rather than trying to develop something else .. If you don't want to lay out a fortune, buy a Uniden LRD2000 Stalker. ...

Ahah. Sounds like this might be going somewhere.

Question though, is it possible for these things to have some sort of "wake up" mode, whereby you could tell by means of a light or something that they are picking up stuff. Thing is on a bike you can't really listen (or can you - Bluetooth maybe), so you need some sort of alert signal. I also have a vague notion that the police radio sends a relatively frequent "keep alive" signal back to base - maybe some one can confirm ro deny that

Sounds rather promising though. [goes off to research Uniden Stalkers - be ironic wouldn't it if the answer to the Stalker turned out to be a Stalker]

[Lou Girardin]

Some issues come to mind;
You'll get alerts from every cop transmitting on that freq, that'll drive you nuts in town.
You're faced with the same issues as non-Valentine detestors, ie. where is the cop, ahead or behind or down a side road. With the added uncertainty of whether they have radar or not.
Until effective jammers become available, the best defence against radar is a good detector, used sensibly.

[Ixion]

Some issues come to mind;
You'll get alerts from every cop transmitting on that freq, that'll drive you nuts in town.
You're faced with the same issues as non-Valentine detestors, ie. where is the cop, ahead or behind or down a side road. With the added uncertainty of whether they have radar or not.
Until effective jammers become available, the best defence against radar is a good detector, used sensibly.

Yes, but I don't care in town because I don't speed in built up areas. And if there's more than one cop, all the more reason to slow down. I don't care if he's ahead of me or behind me , or down a side road. I just want to know that he's somewhere near (or, not somewhere near). I don't suggest that such a device would replace a radar detecter, but supplement it

[avgas]

i actually had a talk to a guy who wants to do something like that no so long ago. He reckons using the 3rd harmonic is the key as you loose alot of the low frequency hum from all the other radio channels (rigs, ambulance etc) and the electrics on the bike (leads etc).
Mate had a brilliant jammer once that worked off the KA band (or is it K?) and hid under his seat (2 transmitters, one in the headlight, one in the brakelight). Wouldnt tell me where i could get one though.
what we actually need is something on the cellphone networks that works like a bulletin board - messeging you that you are entering a danger zone.
...that or the road angel system in NZ

[marty]

a low powered ADF tuned to the police radio freq. could work, but they would have to txmit to set it off. the valentine works like this, indicating the direction the pulse is coming from. the police radios do not pulse a 'here i am' signal. some of the highest producing HP cops i know might talk on the radio twice in a shift, so the ADF thing would be useless.

(BIIIG breath) lou is right, although keeping your eyes peeled, watching other driver behaviour (brake lights coming on 1km ahead - camera car?) and keeping off the SH ways are just as important to avoiding the 5-0.

[Lou Girardin]

a low powered ADF tuned to the police radio freq. could work, but they would have to txmit to set it off. the valentine works like this, indicating the direction the pulse is coming from. the police radios do not pulse a 'here i am' signal. some of the highest producing HP cops i know might talk on the radio twice in a shift, so the ADF thing would be useless.

(BIIIG breath) lou is right, although keeping your eyes peeled, watching other driver behaviour (brake lights coming on 1km ahead - camera car?) and keeping off the SH ways are just as important to avoiding the 5-0.

Why, thank you Marty.
And don't forget the first rule of speeding 1ST IN LINE, GETS THE FINE!