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screeech
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Re: Radar Manual- No Tuning Forks And No Tracking History

by: screeech on

Perhaps people who allegedly know about these things don't want to give too many details as having too much education out there may affect their livelihood...the vip is used to help reduce lag time between the car and the radar which eliminates batching...now you will ask, what's batching? the vip also eliminates the shadowing effect as explained earlier...

jsherk
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by: jsherk on

rank wrote:Where do you see that inference?

When I read that quote about VIP, I just understand it to mean that the unit is using the signal from patrol vehicle computer (via vip/vss cable) to compare against the patrol vehicle speed that is being generated by the radar. The radar is receiving multiple signals back and has to determine which one is patrol vehicle speed and which one is target vehicle speed and which ones are neither. When it is not sure about which radar signal is patrol vehicle speed (due to shadowing), it compares it to the patrol vehicle speed from computer and then says "this one matches so it must be the correct patrol vehicle speed" which eliminates the shadowing error.


And after reading argyll, decatur and nanuk comments, I believe that is what they are saying as well.


Of course it could also mean that it actually uses ONLY the patrol vehicle speed from computer when it gets confused and detects the shadowing error. However without putting an engineer from the manufacture on the stand, I don't think we would ever know for sure.


But regardless of how/when it uses the computer speed, there still needs to be a visual check of the speedometer with the patrol vehicle speed displayed on radar during the test, which in my opinion still makes it necessary to prove the accuracy of the speedometer with some external testing or the accuracy of the radar with external tuning forks. Just because they both match/agree does not of itself make them both accurate. It just means that they could be equally inaccurate.

+++ This is not legal advice, only my opinion +++
rank
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by: rank on

jsherk wrote:

When I read that quote about VIP, I just understand it to mean that the unit is using the signal from patrol vehicle computer (via vip/vss cable) to compare against the patrol vehicle speed that is being generated by the radar. The radar is receiving multiple signals back and has to determine which one is patrol vehicle speed and which one is target vehicle speed and which ones are neither. When it is not sure about which radar signal is patrol vehicle speed (due to shadowing), it compares it to the patrol vehicle speed from computer and then says "this one matches so it must be the correct patrol vehicle speed" which eliminates the shadowing error.


And after reading argyll, decatur and nanuk comments, I believe that is what they are saying as well.

We agree on that. In my original statement a several posts ago, I said that the radar is tied to the ECM...which is true. I suppose it could be said that the data from the ECM is for lack of a more complicated term, is the tie breaker. It has the final say.



jsherk wrote:But regardless of how/when it uses the computer speed, there still needs to be a visual check of the speedometer with the patrol vehicle speed displayed on radar during the test....

We agree on that also. I will now take this opportunity to correct my earlier statement that "it doesn't matter what the speedometer says". This is of course incorrect and the radar instructor never told me this exactly. I should not have worded it in that way. He said something like "With VIP the speed comes from the ECM so tires can't throw the speedometer off". It clearly states in the Genesis operator manual that I read, before the officer locks a speeder, the officer must compare that the speedo reading and the radar patrol speed are the same. If they aren't then no enforcement action will be taken. My apologies to the forum for that misinformation.


jsherk wrote:which in my opinion still makes it necessary to prove the accuracy of the speedometer with some external testing or the accuracy of the radar with external tuning forks. Just because they both match/agree does not of itself make them both accurate. It just means that they could be equally inaccurate.

Again we agree. For example, if tires are changed to a different size without changing the tires size information in the ECM, then the ECM/VSS/speedometer will not match the patrol speed obtained by the antenna.

rank
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by: rank on

screeech wrote:Perhaps people who allegedly know about these things don't want to give too many details as having too much education out there may affect their livelihood...

I suspect you're correct. Which is shameful and begs the question, why are these people in this forum then? To spread half truths? It is a truly sad when some civil servants paid with tax payer dollars to serve and protect are more concerned with their own livelihood and power than they are about truth.

jsherk
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by: jsherk on

rank wrote:It clearly states in the Genesis operator manual that I read, before the officer locks a speeder, the officer must compare that the speedo reading and the radar patrol speed are the same.

Do you know what section of the manual it says this in?

+++ This is not legal advice, only my opinion +++
rank
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by: rank on

jsherk wrote:
rank wrote:It clearly states in the Genesis operator manual that I read, before the officer locks a speeder, the officer must compare that the speedo reading and the radar patrol speed are the same.

Do you know what section of the manual it says this in?

Nope. I wasn't allowed to take pictures or make copies. I just took notes and asked questions

screeech
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by: screeech on

"why are these people in this forum then? To spread half truths? It is a truly sad when some civil servants paid with tax payer dollars to serve and protect are more concerned with their own livelihood and power than they are about truth." Where are the half truths? Who said they were Civil Servants paid by tax payer dollars?

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