You have a Mazda CX-5 and an R7? What settings work?

Maz3

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Keep the insurance discount, sell the R7 and add both to the Theia fund 😁

Actually I just got an R7 and like it so far, good luck getting it to work with the CX-5
Theia has always been the plan. The deep discount on the R7 made me jump. They're C$1,000 here.

I have great news on my filter experiment, but rum comes first 😁
 

DC Fluid

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Theia has always been the plan. The deep discount on the R7 made me jump. They're C$1,000 here.

I have great news on my filter experiment, but rum comes first 😁
News first, or rum will burn!!! :moreevil:

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Maz3

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Well here we go...

So expanding on @DC Fluid suggestion to mask the rear horn antenna with a metallic product, I used aluminum foil from my hat, for my experiment.

With the rear horn clear of any obstructions my R7 alarms almost constantly to K band 24.123/4 GHz, to the rear from my CX-5's BSMs. No matter what settings I use including K band 30%, Rear 30%, MRCD on, TSR on, K Filter on, my R7 continues to alert to the BSMs. The R7 is mounted to the windshield, to the right of the rear view mirror, at the headliner.

Covering the rear horn with aluminum foil stopped the BSM alerts from the rear completely. This is no surprise as it blocks all signals to the rear horn. On my test course there are two speed signs; 24.146 and 24.147 GHz respectively, and interestingly when passing these two signs with the rear horn completely covered, the arrows would flip from front, to side, but not to the rear. This leads me to wonder if part of the arrow switching algorithm is a sudden decrease in signal strength from the front horn, as the arrows never switched to the rear.

In this series of photos I am stationary in a strip mall with the R7 alerting to a door opener at 24.187 GHz (you'll note there are two front sources), on the front horn. with the rear horn fully covered with foil.
PXL_20210405_233124632.jpg

Remove the foil and the R7 immediately leaves the 24.187 GHz door opener and alerts to the CX-5 BSM on the rear horn. Signal strength would move from a couple bars to five bars.
PXL_20210405_233135381.MP.jpg

Then when another piece of foil cut to 24.125 GHz wavelength of 1243 mm (circular polarization) the R7 switches back to the front horn, and the 24.187 GHz door opener. Note the COVID mask used to hold the foil into place :laugh: I forgot to bring some tape, and while the solid foil could be formed into place, the foil with the circle cutout is layered between two pieces of packing tape. I did this so the foil wouldn't tear when I was cutting it out with my exacto knife. Silly me...
PXL_20210405_233616777.jpg

So that was stationary, what happened while moving... In short, the R7 operated normally and wasn't preoccupied with my BSMs. With K at 100%, Rear @ 70%, MRCD off, TSR, off, K Block on, the R7 was fairly quite, but did alert once in a while to the BSMs - more than I would like for a daily drive. This was particularly true when stopped in traffic providing signal bouncing that the R7 was picking up on the front horn.

However, leaving K @ 100%, Rear @ 50%, MRCD on, TSR off, K Block on - very quite! Better yet, the arrows would switch to rear when I passed the two speed boards, albeit fairly quick to the sides, the rear switch was delayed up to ~ 70M.

It would appear that the foil with the circular cutout is attenuating signals of approx. 24.125 GHz and lower, significantly enough that the R7 filters can address the BSM alerts with filter functions. It was very clear to me that the circular foil had to be tight against the R7 case for the best results. This is likely because there is a gap between the interior horn and the exterior case, allowing for signals to creep in between the foil and the horn face.

The ideal would be for a machinist who was really into RD testing to cut a piece of very light (beer can) aluminum sized to match the rear horn with a very exact 1243 mm circular cut-out. Include a couple of flaps that could be folded around the face of the horn to hold the piece in place, it would be perfect. Millions of dollars to be made there I think :rofl:

Although not pretty, my R7 now appears to be usable in my CX-5, and for most signals (all Ka for sure) the arrows will remain functional. The other benefit is that the R7 CPU isn't being tied up with electronic filtering that has been dealt with mechanically. I will see if I can find some light gauge aluminum, and install it directly against the horn for cosmetics and function.

What a great community we have here that everyone involved, including those who don't even own a CX-5 (@DC Fluid ) can compare notes to find a solution for the R7 to be run in a CX-5. If others could give this a try, it would be wonderful if the results could be replicated. Tight fit against the case, and around the inside edge to the display is paramount to block any signal gaps..

Back to the rum :drinking: <- Implies I don't drink alone :rofl:
 
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DC Fluid

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Well here we go...

So expanding on @DC Fluid suggestion to mask the rear horn antenna with a metallic product, I used aluminum foil from my hat, for my experiment.

With the rear horn clear of any obstructions my R7 alarms almost constantly to K band 24.123/4 GHz, to the rear from my CX-5's BSMs. No matter what settings I use including K band 30%, Rear 30%, MRCD on, TSR on, K Filter on, my R7 continues to alert to the BSMs. The R7 is mounted to the windshield, to the right of the rear view mirror, at the headliner.

Covering the rear horn with aluminum foil stopped the BSM alerts from the rear completely. This is no surprise as it blocks all signals to the rear horn. On my test course there are two speed signs; 24.146 and 24.147 GHz respectively, and interestingly when passing these two signs with the rear horn completely covered, the arrows would flip from front, to side, but not to the rear. This leads me to wonder if part of the arrow switching algorithm is a sudden decrease in signal strength from the front horn, as the arrows never switched to the rear.

In this series of photos I am stationary in a strip mall with the R7 alerting to a door opener at 24.187 GHz (you'll note there are two front sources), on the front horn. with the rear horn fully covered with foil.
View attachment 176475

Remove the foil and the R7 immediately leaves the 24.187 GHz door opener and alerts to the CX-5 BSM on the rear horn. Signal strength would moce from a couple bars to five bars.
View attachment 176476

Then when another piece of foil cut to 24.125 GHz wavelength of 1243 mm (circular polarization) the R7 switches back to the front horn, and the 24.187 GHz door opener. Note the COVID mask used to hold the foil into place :laugh: I forgot to bring some tape, and while the solid foil could be formed into place, the foil with the circle cutout is layered between two pieces of packing tape. I did this so the foil wouldn't tear when I was cutting it out with my exacto knife. Silly me...
View attachment 176479

So that was stationary, what happened while moving... In short, the R7 operated normally and wasn't preoccupied with my BSMs. With K at 100%, Rear @ 70%, MRCD off, TSR, off, K Block on, the R7 was fairly quite, but did alert once in a while to the BSMs - more than I would like for a daily drive. This was particularly true when stopped in traffic providing signal bouncing that the R7 was picking up on the front horn.

However, leaving K @ 100%, Rear @ 50%, MRCD on, TSR off, K Block on - very quite! Better yet, the arrows would switch to rear when I passed the two speed boards, albeit fairly quick to the sides, the rear switch was delayed up to ~ 70M.

It would appear that the foil with the circular cutout is attenuating signals of approx. 24.125 GHz and lower, significantly enough that the R7 filters can address the BSM alerts with filter functions. It was very clear to me that the circular foil had to be tight against the R7 case for the best results. This is likely because there is a gap between the interior horn and the exterior case, allowing for signals to creep in between the foil and the horn face.

The ideal would be for a machinist who was really into RD testing to cut a piece of very light (beer can) aluminum sized to match the rear horn with a very exact 1243 mm circular cut-out. Include a couple of flaps that could be folded around the face of the horn to hold the piece in place, it would be perfect. Millions of dollars to be made there I think :rofl:

Although not pretty, my R7 now appears to be usable in my CX-5, and for most signals (all Ka for sure) the arrows will remain functional. The other benefit is that the R7 CPU isn't being tied up with electronic filtering that has been dealt with mechanically. I will see if I can find some light gauge aluminum, and install it directly against the horn for cosmetics and function.

What a great community we have here that everyone involved, including those who don't even own a CX-5 (@DC Fluid ) can compare notes to find a solution for the R7 to be run in a CX-5. If others could give this a try, it would be wonderful if the results could be replicated. Tight fit against the case, and around the inside edge to the display is paramount to block any signal gaps..

Back to the rum :drinking: <- Implies I don't drink alone :rofl:
Your circular filter baffles me as to how that could be a filter, but oh well, not my forte.
I am a machinist however. And I do love my CMs.
But I'm not headed down to the shop to machine any bear cans anytime soon.! LOL.

If you look at my pics of the R7 with cover off, the rear horn is a long way from the outer case, there is a lens out there too.
Would a little flat piece of aluminum with your hole in it work when mounted right against the horn?
What does the lens shape do? Would it affect your wavelength before entering horn?
If that was a worry, you could transfer your foil to the inside of the case before the lens, for a more pleasing appearance.

Be thankful it's working.
You could have a new Max 360c acting up. :rolleyes:
That's a hint....
Post automatically merged:

And more importantly, why the [email protected]#K haven't you locked out those door openers yet??!!
200.gif
 
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Maz3

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Your circular filter baffles me as to how that could be a filter, but oh well, not my forte.
I am a machinist however. And I do love my CMs.
But I'm not headed down to the shop to machine any bear cans anytime soon.! LOL.

Think of having a block that you're trying to fit into a hole. If the block is smaller than the hole, it will pass through. If the block is bigger than the hole, try as you may it will not pass through.

Radio (light for that matter) has "size" which is it's wavelength, inversely proportional to the frequency. The higher the frequency, the smaller the wavelength. That's why old school CB antennas could be as long as 102" for 27 MHz, while listening to Rock 101 at 100 Mhz can work fine with a much shorter car antenna - a basic explanation, but it makes the point.

So if the wavelength of a given frequency is longer than the gap in the metal, it cannot pass. That's why you can look through the door of your microwave oven without cooking your eyes. The diameter of the little holes in the door that you look through are smaller than the wavelength of the microwave cooking the food.

Yes, the aluminum would fit nicely behind the lens in your photo and that is likely what I'll do. I'm using a crappy tire micrometer, so not too trustworthy LOL.

As radio frequency gets higher it starts to act more like light. Radar is fairly line of sight (not counting bounces) while very low frequencies will bounce around the entire earth. Because microwave has light properties the lens is to focus the microwave radar signal into the horn antenna to give the detector more sensitivity. The lens doesn't change the frequency of the radar signal, hence the wavelength cannot change either. The phase of the signal can be changed, but if done evenly there is no negative impact. Anyone see any errors in my explanation feel free to correct me. Cough, cough, gagging on geekdom :laugh:

What's the issue you're having with the new Max 360C? :eek:
 
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DC Fluid

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So your hole size theory works for me if:
24.125 wavelengths are the same in amplitude, making it a more round ball shape, equal in length and height, otherwise it would be long like a pencil and fit through the hole.
Am I getting the jist?

Now, does the hole automatically exclude all other signals of wavelengths 24.125 or longer?
Would I guess that no K Band below 24.125 can get through either?
So you will have K Band rear above 12.125 only?
 

Maz3

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So your hole size theory works for me if:
24.125 wavelengths are the same in amplitude, making it a more round ball shape, equal in length and height, otherwise it would be long like a pencil and fit through the hole.
Am I getting the jist?

Now, does the hole automatically exclude all other signals of wavelengths 24.125 or longer?
Would I guess that no K Band below 24.125 can get through either?
So you will have K Band rear above 12.125 only?
You've basically got it. Think of amplitude as height or volume/strength of the signal.

If you looked at a signal on an oscilloscope, the height is the amplitude, and the wavelength is the horizontal distance of one complete cycle.

So 25.125 GHz has a wavelength 1.243 cm which is the distance in free space from the start of the radio wave, to the end of a signal cycle.

So yes, any frequency lower than 24,125 GHz will not be received by the rear horn because the wavelengths get longer as the frequency gets smaller, and can't fit throughout the 1.243 cm hole.

There's three conventional antenna polarizations: circular, vertical, and horizontal. Each is determined by the physical orientation of the transmitting antenna. You can mix and match, but the best signal transfer occurs between antennas of the same orientation. If you watch the NZ R7 videos on Redflex speed cameras, the R7 detector is on its side because Redflex is opposite to conventional speed radar.

So I guessed at making my hole a circle. A horizontal, or vertical rectangular hole 1.243 cm wide might work better.

I hope that makes sense. You've got a good grasp of it already.
 
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YelloEye

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The ideal would be for a machinist who was really into RD testing to cut a piece of very light (beer can) aluminum sized to match the rear horn with a very exact 1243 mm circular cut-out. Include a couple of flaps that could be folded around the face of the horn to hold the piece in place, it would be perfect. Millions of dollars to be made there I think :rofl:
As an American, I think your measurment is off by a little over a meter. 😉
Post automatically merged:

You've basically got it. Think of amplitude as height or volume/strength of the signal.

If you looked at a signal on an oscilloscope, the height is the amplitude, and the wavelength is the horizontal distance of one complete cycle.

So 25.125 GHz has a wavelength 1.243 cm which is the distance in free space from the start of the radio wave, to the end of a signal cycle.

So yes, any frequency lower than 24,125 GHz will not be received by the rear horn because the wavelengths get longer as the frequency gets smaller, and can't fit throughout the 1.243 cm hole.

There's three conventional antenna polarizations: circular, vertical, and horizontal. Each is determined by the physical orientation of the transmitting antenna. You can mix and match, but the best signal transfer occurs between antennas of the same orientation. If you watch the NZ R7 videos on Redflex speed cameras, the R7 detector is on its side because Redflex is opposite to conventional speed radar.

So I guessed at making my hole a circle. A horizontal, or vertical rectangular hole 1.243 cm wide might work better.

I hope that makes sense. You've got a good grasp of it already.
Stellar work on what's effectively a prototype there. Curious as to why your CX5 seems to shoot so much stronger than say mine. Or maybe you just got a really hot R7 unit.
 

Jdem

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You've basically got it. Think of amplitude as height or volume/strength of the signal.

If you looked at a signal on an oscilloscope, the height is the amplitude, and the wavelength is the horizontal distance of one complete cycle.

So 25.125 GHz has a wavelength 1.243 cm which is the distance in free space from the start of the radio wave, to the end of a signal cycle.

So yes, any frequency lower than 24,125 GHz will not be received by the rear horn because the wavelengths get longer as the frequency gets smaller, and can't fit throughout the 1.243 cm hole.

There's three conventional antenna polarizations: circular, vertical, and horizontal. Each is determined by the physical orientation of the transmitting antenna. You can mix and match, but the best signal transfer occurs between antennas of the same orientation. If you watch the NZ R7 videos on Redflex speed cameras, the R7 detector is on its side because Redflex is opposite to conventional speed radar.

So I guessed at making my hole a circle. A horizontal, or vertical rectangular hole 1.243 cm wide might work better.

I hope that makes sense. You've got a good grasp of it already.

You’re a very intelligent man @Maz3 🙌🏼
 

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