| colossus |
| I was testing out a new Zodiac Radar the other day and noticed it only rings in Highway mode, it gets not hits in city mode, even when I drove by a radar van. What gives? It also rings at most intersections? Is it not detecting radar, or what is it picking up? |
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| sparkycivic |
it is probably a typical cheapie detector that does not process the signals it receives. essentially, it's a radio receiver tuned to 3 bands at once. X, K, and Ka. in highway mode it's detecting any signals that it receives and assumes them to be radar signals(as opposed to communications, satellite uplinks, automatic door radar, etc). more expensive detectors perform analysis on the signals to determine if they are actual radar or just communications/other.
I have omitted the Laser funciton because it's a light detector not unlike the one in your TV for the remote control, and it's not subject to all the bouncing random signals like radio sigs do.
In city mode, your detector is just setting itself to ignore the weakest level or two of signal strength since they know that cities are polluted signal zones, especially at, or near the police X, K, and Ka bands which are hard to discriminate. radar vans usually never get higher than 30% on our signal scales, so you might never get a alarm from them, unless you are in highway mode or have an expensive detector that will recognize the weak, yet important photo-radar-van signal.
sad but true
hope this helps.
somebody please sticky this since it seems to be a popular topic, and the search is obvoiusly insufficient. |
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| Qoo |
I got some question too.
can we put small antenna on the 4 cornor of the car and link them to the radar detector?
so that it gives up more range?
I know this is a noob/dumb question but it has been bugging me for years.
the wave theory I learn at school tells me antenna is like this
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so we should be able to pick up before the radar actually hit our car?:dunno: |
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| sparkycivic |
| dipole antennas and other antennas like them won't work at the multi-gigaHertz frequencies that we are dealing with. the detector is using a tuned cavity antenna. dipoles might work, but you still won't get teh signals to actually travel along a wire because it's so high. a waveguide would have to be used to bring a signal to the unit. :google: "waveguide" to see how impractical that would be :P |
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