What does a Bushnell gun look like? Bushnell vs. Stalker vs. Cadillac BSM

[Jon at Radenso]

I thought this might be useful information for members of the community to have. Ignore the frequency scale since I did not recalibrate it for each recording.

Bushnell

Stalker

Cadillac BSM

 

[Vortex]

So the Bushnell is a standard CW gun like the Stalker and unlike the FM Cadillac BSM. What do door openers look like?

Thanks for posting up the photos showing what the radar emissions look like. I'm assuming the frequencies displayed on the chart (35.5) aren't correct?

Also, is the big spike on the right of the Cadillac image part of the BSM or an artifact of your test equipment?

 

[Jon at Radenso]

So the Bushnell is a standard CW gun like the Stalker and unlike the FM Cadillac BSM. What do door openers look like?

Thanks for posting up the photos showing what the radar emissions look like. I'm assuming the frequencies displayed on the chart (35.5) aren't correct?

Yes, the Bushnell is a standard CW gun and is absolutely nothing like the Cadillac signal (or any other BSM). The Cadillac signal is not just frequency modulated, but also pulse modulated (there is lots of sparsity). This is a pretty representative sample of a BSM.

Now just for fun, let's zoom REALLY close to look at things how Theia sees them. Now we can start to see a bit of a difference - the bushnell has more oscillation around the center carrier frequency, but we are talking on an order of a few khz. As Rob said in our video, there is no such thing as a truly pure signal - if we zoom in this far, Theia can tell the differences between an Eagle, a Bushnell, a Stalker, etc. But it's patently obvious that both the Bushnell and the Stalker are CW guns.

Fun fact: this slight oscillation in frequency is what multipath interference looks like! So if I wrote a filter to gate signals +/- n number of khz, my radar detector would not be able to pick up handheld police guns of all kinds!

Further, as we zoom in this close, the differences between the Bushnell and the Cadillac are even more pronounced - the pulse modulation is more clearly visible.

Asper your request, here is a door opener:

 

[Heywood]

I can see it. Man, that Bushnell signature is so messy. Kind of screws Escorts claims of why it filters out Bushnell’s but allows other blatant offenders.

I have a feeling.
I know it as I’ve felt it before.

Oh that’s right.
Escort trying to “Blow sunshine up my butt” with spin

 

[Jon at Radenso]

I can see it. Man, that Bushnell signature is so messy. Kind of screws Escorts claims of why it filters out Bushnell’s but allows other blatant offenders.

It is an interesting question why a frequency based filter (if it exists) blocks "clean" signals that oscillate maybe 50khz, yet let through BSMs that sweep 200mhz.

 

[Vancity23]

Jon thanks for posting those pictures very informative, learning so much. These again demonstrate how different and advanced your technology is compared to how dated the existing legacy units are...

 

[Heywood]

It is an interesting question why a frequency based filter (if it exists) blocks "clean" signals that oscillate maybe 50khz, yet let through BSMs that sweep 200mhz.

I totally agree. I’m surprised that Escort doesn’t ignore the Stalker as well.

There’s very little “Width” between the 2 CW signals vs the wide spread of the Caddie signal that it can’t filter out.
Yet somehow, Escort expects us to buy in that this was something done intentionally.

I really don’t know why they make the claims they do or the reasoning? It’s like an alternate universe that they live in.

 

[alloy00]

Pardon me if I missed this in your other posts Jon

Could Theia have "seen" the signal well enough to have created these images? Not necessarily to "output" them the same as an SDR - but is the information which Theia understands this detailed?

 

[Jon at Radenso]

You guys wanna see something really crazy? Here's what a stalker looks like when handheld and shaking. This makes the oscillation on the Bushnell look like nothing!

Post automatically merged: Nov 19, 2019

Pardon me if I missed this in your other posts Jon

Could Theia have "seen" the signal well enough to have created these images? Not necessarily to "output" them the same as an SDR - but is the information which Theia understands this detailed?

Yes, some of these are actually taken using Theia's RF front end as an antenna hooked up to an ettus radio.

 

[InsipidMonkey]

I totally agree. I’m surprised that Escort doesn’t ignore the Stalker as well.

It does when it's sleeping

 

[Heywood]

One last thing.

Let’s not let common sense, examples of proof, high tech R&D get in the way of a good story.

 

[InsipidMonkey]

Is that just the Doppler shift from the radar gun moving relative to the receiver? What is the time scale and amplitude of the frequency shift?

And what is the bandwidth of the CW signal for the Stalker and Bushnell?

 

[Vortex]

You guys wanna see something really crazy? Here's what a stalker looks like when handheld and shaking. This makes the oscillation on the Bushnell look like nothing!

View attachment 134525

Wow. Yeah I remember Rob mentioning you guys are able to see handshake and things like that. Does that affect Theia's ability to recognize the gun as a Stalker?

In practice when out driving, do you think you'd be able to still see that? I'm sure there's a lot more going driving down the road vs sitting in a lab. Do realworld dynamics and noise impact your ability to still correctly inference these guns?

 

[Jon at Radenso]

That frequency shift is over a pretty long time scale, maybe a couple hundred milliseconds.

Multipath interference, doppler shift, etc, are absolutely real world phenomenons. That is the role of the DSP that we developed before we send Rai the data - the DSP does the job of drawing the pictures "correctly" so to speak so Rai can do her magic.

 

[ARkaband]

Looks like a normal CW gun to me. Thanks for sharing.

 

[V1Jake]

Holy smokes

 

[cihkal]

Wow thanks for sharing this information!

Knowledge is power, no doubt!

I prefer that a manufacturer shows me acutal information with certain claims so I can understand better for myself.

Jon, thanks for educating consumers so they ultimately understand the threats around then more, what products on the market can/cannot do, and why certain things might be happening.

Another reason for anyone reading this, if you like these sort of things, to consider supporting Radenso next time you're considering a CM purchase.

Who else is doing this for the community?

Sent from my VOG-L29 using Tapatalk

 

[Bocephus]

Thanks for sharing, and glad to see we aren't all mushrooms around here!

 

[Smason]

Might be a dumb question, but do radar guns "leak"? Any way to detect in advance of intentional transmission?

 

[CobawLT2010]

Thanks for sharing Jon.

I’m still saying that a lot of these BSM’s could be filtered on a superhet if new programming logic And software were developed. Not to the effect of Thea but still... it could be done.