Did anyone consider radar/lasar detectors for the lake?

[lawn psycho]

Originally Posted by Skip

That all said Bear Islander's claims are not only plausible, but I have seen those same effects first hand.

I wonder if it's brand specific? I would have thought the metal housing alone would prevent the intereference from radar. I'd think you have to be fairly close in order for that too happen.

What is MP using for units? Frequency/power?

[Skip]

Originally Posted by lawn psycho

I wonder if it's brand specific? I would have thought the metal housing alone would prevent the intereference from radar. I'd think you have to be fairly close in order for that too happen.

What is MP using for units? Frequency/power?

Very few modern sonar/depth finders have metal housings....most are plastic.

Additionally RF energy can be coupled into the device via the power leads. So a power lead that may be a derivative of the wave length of a particular RF transmitter could help induce interference into the device.

Finally a particular brand of Sonar may have an internal oscillator that is harmonically related to the frequency of the radar unit.

There are multiple ways/reasons that the particular device BI has, or the unique way that it is installed, could induce the particular interference he is seeing.

That's why marine electronics technicians that know what they are doing, and will work for a reasonable price, are a very scarce resource.

Finally this is why I beleive that while BI's claims are rare, they are plausible and verifiable in real world situations.

[lawn psycho]

Originally Posted by Skip

Very few modern sonar/depth finders have metal housings....most are plastic.

Additionally RF energy can be coupled into the device via the power leads. So a power lead that may be a derivative of the wave length of a particular RF transmitter could help induce interference into the device.

Finally a particular brand of Sonar may have an internal oscillator that is harmonically related to the frequency of the radar unit.

There are multiple ways/reasons that the particular device BI has, or the unique way that it is installed, could induce the particular interference he is seeing.

That's why marine electronics technicians that know what they are doing, and will work for a reasonable price, are a very scarce resource.

Finally this is why I beleive that while BI's claims are rare, they are plausible and verifiable in real world situations.

I've never looked at my sound unit other than wax around it. I suspect the power leads are not shielded and/or twisted.

So now I have to wonder why the shipboard radars don't interfere with the depth sounders?

[Dave R]

Originally Posted by Skip

Very few modern sonar/depth finders have metal housings....most are plastic.

Additionally RF energy can be coupled into the device via the power leads. So a power lead that may be a derivative of the wave length of a particular RF transmitter could help induce interference into the device.

Finally a particular brand of Sonar may have an internal oscillator that is harmonically related to the frequency of the radar unit.

There are multiple ways/reasons that the particular device BI has, or the unique way that it is installed, could induce the particular interference he is seeing.

That's why marine electronics technicians that know what they are doing, and will work for a reasonable price, are a very scarce resource.

Finally this is why I beleive that while BI's claims are rare, they are plausible and verifiable in real world situations.

During my time working in Bell Labs, I did some electromagnetic interference and susceptibility testing on telecom gear. This is stuff that is carefully shielded to prevent interference and you would not believe the ways microwave radio waves can get into stuff. There's no requirement that a depth finder has to meet a susceptibility rating, so it would not surprise me at all if it could act as a radar detector.

[NoBozo]

I think the FCC is VERY particular about how electronic devices radiate energy. Look at the documentation that comes with everything you buy that "may" radiate energy. Your garrage door opener for example, etc. A term that comes to mind is "May Not" (meaning not permissible) interfere with other gadgets within a certain range.

Now if a radar were able to penetrate another gadget so easily, I would think the FCC would have something to say about it. The inside of the plastic case on my computer has metal/foil shielding to prevent either intrussion or radiation outward, by Rf energy which might interfere with the operation of other electronic devices. NB

[Skip]

Originally Posted by NoBozo

I think the FCC is VERY particular about how electronic devices radiate energy. Look at the documentation that comes with everything you buy that "may" radiate energy. Your garrage door opener for example, etc. A term that comes to mind is "May Not" (meaning not permissible) interfere with other gadgets within a certain range.

Now if a radar were able to penetrate another gadget so easily, I would think the FCC would have something to say about it. The inside of the plastic case on my computer has metal/foil shielding to prevent either intrussion or radiation outward, by Rf energy which might interfere with the operation of other electronic devices. NB

You are confusing spurious RF energy emissions which are limited or eliminated by FCC type acceptance, with a case of a legally permitted RF source interfering occassionally with a third party device. It happens all the time in the real world as all operating conditions cannot be controlled or anticipated for various reasons. There would be nothing "illegal", even via the FCC's rigid standards, to prevent the anomaly that BI experiences.

Anyway, we have strayed significantly from the original post's question and intent. By the way, to get back to the original post, a radar or laser detector would probably work significantly better over open water than its intended terrestial application. Since the radar/lidar units operate within the same parameters frequencywise as their land use cousins than they would operate as least as well over the water, where they are not currently banned under existing NH regulations.

[lawn psycho]

Originally Posted by Skip

By the way, to get back to the original post, a radar or laser detector would probably work significantly better over open water than its intended terrestial application. Since the radar/lidar units operate within the same parameters frequencywise as their land use cousins than they would operate as least as well over the water, where they are not currently banned under existing NH regulations.

Skip, that is what I suspect as well. There is probably much less interference out on the water as well but I do wonder about how the radar units people have would be detected as a false positive.

I will tell you that my land-based unit that I currently own sniffs radar/lasar enforcement with very good accuracy. The only caveat is when you are the only car on the road.

To anyone who considers buying a radar detector (for land or water), you get what you pay for.