BSM K-Band Filter - possible with firmware or not? R3 / R7?

metroplex

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Does anyone know if there is a hardware limitation on the R3 and R7 that would not allow a filter to be setup for 24.160 and other K-band BSM frequencies via a firmware update?
When I first started using my DFR9 and R3 about 2 years ago, there was rarely if any K-Band hits from BSM systems other than the Japanese cars (which seemed to go away with the firmware update) and then it was just Cadillac. Now within the last year or so, the DFR9 and R3 are now FCA/Dodge/Jeep detectors. Every time I hear a K-Band ping, 90% of the time it is a FCA product at 24.160 GHz. (or some variation, but 24.160 is very common).
 

NorEaster18

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Those are pretty nasty BSMs. I see them with both my R3 and my V1G2.

The problem is that this is right where real K band often transmits. One of my guns reliably transmits right between 24.160 - 24.162. Blocking that would be a big danger if you face any real K Band. The K Block feature is already a pretty risky feature. I have seen legit K band transmit in that frequency area, albeit much less frequently than in the 24.16x range.

The best thing to do right now is to notice the distinct difference between how the detector alerts to the BSM and a real source. From my experience, the R3 is especially good at conveying the difference between these two in how it responds and ramps up/down.
 

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The only ones that can say that for sure are Uniden themselves, but maybe someone that has more experience looking into these device's firmware can chime in with their thoughts and experiences. I know there are few people here that poke around with that sort of thing. The rest is pretty much speculation.

My opinion is that it's a development limitation, i.e. Uniden needs to have access to and have the desire to develop better filtering for their existing devices, which may or may not make economic sense to them. Barring that, the two hardware limitations are sweep time and processing power. Like other currently available detectors, the R series detectors receive only a tiny slice of the radio spectrum at any given time. Analyzing and identifying a signal is tough when you can only see a bit of it at a time. The signal may change during the time it takes to sweep over to the next portion of it, or an entirely different signal may be located right next to the first, or a new transmission source may being broadcasting on top of it as you sweep the original. New and upcoming detectors like the V1G2 and Theia attempt to tackle this problem by scanning the spectrum simultaneously and very quickly, and scanning very large chunks of the spectrum instantaneously, respectively. Their designs eliminate a lot of the unknowns that come with scanning the spectrum with a "traditional" detector receiver design.

But just because it's difficult doesn't mean it's impossible. There are a lot of clever tricks that can be applied to filter out and isolate signals with both types of receiver designs, and there are even more tricks to be able to do that filtering efficiently enough to run on the low power CPUs in the R series detectors. Uniden does eliminate a lot of K band falsing already. I think they can do even better, and I have a few filtering ideas that may or may not work. But I don't design radar detectors, and I'm sure those that work at Uniden/Attowave have a lot more ideas than I do, but just not enough time or incentive to implement them.
 

GTO_04

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Does anyone know if there is a hardware limitation on the R3 and R7 that would not allow a filter to be setup for 24.160 and other K-band BSM frequencies via a firmware update?
When I first started using my DFR9 and R3 about 2 years ago, there was rarely if any K-Band hits from BSM systems other than the Japanese cars (which seemed to go away with the firmware update) and then it was just Cadillac. Now within the last year or so, the DFR9 and R3 are now FCA/Dodge/Jeep detectors. Every time I hear a K-Band ping, 90% of the time it is a FCA product at 24.160 GHz. (or some variation, but 24.160 is very common).

Are K filter and TSF enabled? If they are not currently enabled they may help. Which firmware are you running? I have stayed with 1.37 on my R1. Based on what I have read on the forum, it seems to do very well with BSMs compared to newer firmware versions, especially in the 24.16 to 24.17 GHz range.

GTO_04
 

NorEaster18

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I didn't enable TSF but have K-Block / K-Filter on. I'm using 1.54
TSF does help a lot! I always run with it on. From my testing, it really doesn’t add much of a delay at all.

I have also found 1.50 to be quieter than 1.54. For example, I never see Mazda falses on 1.50, but I did see them when I tried 1.54. Immediately rolled back to 1.50. I seriously believe it is the best firmware for the R3, just barely edging out 1.37 because of how much quieter it can be.
 

GTO_04

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TSF does help a lot! I always run with it on. From my testing, it really doesn’t add much of a delay at all.

I have also found 1.50 to be quieter than 1.54. For example, I never see Mazda falses on 1.50, but I did see them when I tried 1.54. Immediately rolled back to 1.50. I seriously believe it is the best firmware for the R3, just barely edging out 1.37 because of how much quieter it can be.
K block (available on FW 1.50) is a plus for BSM filtering.

GTO_04
 
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NoahWL

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+1 for TSF helping a lot with BSM (R7). Last week I turned it off for the first time and I get a LOT more 1-2 bar BSM falses all around. Hondas false from further away and for longer, and I've started getting noticeably more single chirps in the 160-168MHz range. I'll be turning it back on soon, as I didn't expect it to make that much of a difference.
 

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I'd got a 24.163 last night from a car ahead of me. I thought it was a BSM from that car, maybe a Pacifica coz there was no other car on the road at the time. I was 10 mph over so I caught up with that car. It turned out it was a LEO. I guess I got lucky he didn't stop me. So be careful with those 24.260 +/ - Ghz
 

NoahWL

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I'd got a 24.163 last night from a car ahead of me. I thought it was a BSM from that car, maybe a Pacifica coz there was no other car on the road at the time. I was 10 mph over so I caught up with that car. It turned out it was a LEO. I guess I got lucky he didn't stop me. So be careful with those 24.260 +/ - Ghz
Scary. Was the alert full strength or about the same as other BSM falses? I would've ignored 24.163 as well at +10.
 

Izzyrd

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Scary. Was the alert full strength or about the same as other BSM falses? I would've ignored 24.163 as well at +10.
It was low strength at first and so I kinda ignored it then when I got closer it did increase and eventually went red and at that point I could already recognize that markings of the dark colored LEO car.
 

NoahWL

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It was low strength at first and so I kinda ignored it then when I got closer it did increase and eventually went red and at that point I could already recognize that markings of the dark colored LEO car.
Sounds like front facing only so at least all he could do is guess what your speed was coming up behind him. What a pain.

I think situations like this could be better handled by many detectors. What if Uniden implemented a feature that alerted the user to whether or not a FM signal was detected alongside a K band carrier? Obviously picking out legitimate police K radar from a BSM polluted spectrum is tough. But if the only thing detected is a single K carrier, then I'd think you could be pretty sure it's, at the very least, not a BSM.
 
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Izzyrd

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Sounds like front facing only so at least all he could do is guess what your speed was coming up behind him. What a pain.

I think situations like this could be better handled by many detectors. What if Uniden implemented a feature that alerted the user to whether or not a FM signal was detected alongside a K band carrier? Obviously picking out legitimate police K radar from a BSM polluted spectrum is tough. But if the only thing detected is a single K carrier, then I'd think you could be pretty sure it's, at the very least, not a BSM.
It's definitely a great but probably hard to do. If there was a Pacifica driving along that cop, I would have assumed it was from that car coz they literally are on the same freq. Anyhow, I noticed that a real police K-band constant-on is persistent and obviously get stronger as you get closer to the source while BSM's are mostly short range and is gone in a couple seconds. But if a LEO uses Instant-on then it will be extremely difficult.
 

NoahWL

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It's definitely a great but probably hard to do. If there was a Pacifica driving along that cop, I would have assumed it was from that car coz they literally are on the same freq. Anyhow, I noticed that a real police K-band constant-on is persistent and obviously get stronger as you get closer to the source while BSM's are mostly short range and is gone in a couple seconds. But if a LEO uses Instant-on then it will be extremely difficult.
Yeah, a lot of the time the BSM signals fade in and out and that gives it away. Although in my experience, on the highway when there are less cars packed together than city streets, they tend to lock on more. Chrysler vehicles are probably the worst offenders I've seen in that respect, though I don't see many around here. Jeeps are pretty bad too, but I notice they'll switch between the 24.160 range and 24.084-ish, I think it is? Hondas I notice definitely fade more, and it's always a giveaway when their signal sweeps between 24.199-24.204 or so.

Side note, I turned TSF back on a couple days ago. I had K turned down to 30% trying to get it to shut up with it off. Now back to 50% and it's way quieter. Still not great though.
 

olemil

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Jeeps are pretty bad too, but I notice they'll switch between the 24.160 range and 24.084-ish, I think it is?
I always see K-24.160 & K-24.168 falses on Jeeps, how do I know, because I drive one,lol. I have my R7 tweaked now so I rarely get a BSM false unless it is from another source.
 

metroplex

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The TSF filter and reducing K-band sensitivity on my R3 didn't do much, because the BSM signals are almost constant if they are alongside me.

Curious what settings did you use for the R7 to reduce that BSM?
 

NoahWL

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The TSF filter and reducing K-band sensitivity on my R3 didn't do much, because the BSM signals are almost constant if they are alongside me.

Curious what settings did you use for the R7 to reduce that BSM?
On the R7 a lot of people reduce the rear horn balance to ~70% (I have mine at 60%) to minimize K falses from behind. From what I've read here from people that have used both, the R3 seems to be the quieter of the two since it doesn't have the rear horn. How much have you lowered the K sensitivity? I barely notice a difference in BSM falses until I get down to ~60%. 40% is better, City mode is best (K band sensitivity is 18% in City). When I'm beside a BSM polluter usually I don't get a false, but directly behind them even City often doesn't completely eliminate it.

I've been trying out City mode and TSF on recently since I very rarely face K band in my area. Busy highway, K at 50% TSF on, empty highway Highway mode/K 100% and TSF off. Definitely take a look at the variety of tests in the testing results section and get a feel for how low of a K sensitivity you're comfortable running. Set it as low as you're willing considering the terrain around you, frequency of K encounters, etc.
 

metroplex

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Thanks!

I've set it as low as 40% and it still picks up FCA vehicles/Jeeps. I'm about ready to turn off K-Band since none of the police here in SE MI seem to run K-band. They are now using K-Band radar signs at I-94 exit ramps that are tight/dangerous to indicate your speed or to tell you to slow down, but otherwise it seems most traffic police are using Ka.
 

Izzyrd

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Thanks!

I've set it as low as 40% and it still picks up FCA vehicles/Jeeps. I'm about ready to turn off K-Band since none of the police here in SE MI seem to run K-band. They are now using K-Band radar signs at I-94 exit ramps that are tight/dangerous to indicate your speed or to tell you to slow down, but otherwise it seems most traffic police are using Ka.
In Royal Oak, I've seen at least three K band LEO's so far. Not sure if it's the same one. Mostly they run Ka but last week, my R3 picked-up a 24.163 from a car ahead of me. I thought it was a BSM from that car, maybe a Pacifica coz there was no other car on the road (Rochester Rd) at the time (around 9pm) I was 10 mph over so I caught up with that car. It turned out it was a LEO. I guess I got lucky he didn't stop me. So be careful with those 24.260 +/ - Ghz when in the area.
 

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