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Something mysterious is blocking car key fobs from working in an Alberta town (cbc.ca)
224 points by drpgq 16 days ago | hide | past | web | favorite | 186 comments

Failing transformers can cause an incredible amount of RF noise. A couple years ago a failing fluorescent light ballast prevented my garage door opener remote from working until it finally gave out (this was when I discovered it as the cause), and it had enough residual power to maintain the interference for a while even after being turned off.

(On a much smaller scale) - I had a plasma ball toy as a kid, the kind you put your finger on and the electricity arcs to your finger. One day I broke the glass housing. Curious what would happen, I plugged it in - the radio in the kitchen AND the TV in the living room both simultaneously wouldn't run when the broken plasma bulb was plugged in. I did this several times as a prank on unsuspecting family members and then the unit burned out/wouldn't turn on. I still don't know how dangerous this was to do(if at all).

My scale wouldn't record my body fat for months until i turned off my plasma ball and it started working again. I was livid thinking it broke.

The most dangerous part of that would probably be being caught by the FCC.

I used to enjoy wrapping a metal slinky around the base of mine. Then whenever I touched metal to it I’d get little sparks. Must have been acting as an antenna, but I wonder what exactly was going on.

It's acting like a capacitor.

I have always wanted a plasma globe but have never gotten one because I've been worried about how much radio noise they might generate and if it would interfere with WiFi etc.

Yeah, in addition most cheap(< $200) wireless modules are pretty susceptible to front end overload. If strong enough the RF noise doesn't even need to be in the same spectrum.

Even my 2m Kenwood D710 mobile in my car will break squelch on some drive throughs.

Tesla had a similar issue when someone started taking them too close to radio towers up on the hills. Luckily they were able to build a foil shield so they could get the RFID spot to pick them up.

Neon sign transformers are routinely the cause of such interference as well:


A grocery store has a lot of florescent lights. More opportunities for failure.

IS this why cell signal always seem to be horrible in grocery stores (aside from them being large concrete-block buildings?

Steel siding and roofing blocks cell signal, too? My home has aluminum siding and steel roof and until my wife and I got S9's we had horrible reception in the house. Had to install a cell booster with the antenna up on the roof.

> Had to install a cell booster with the antenna up on the roof.

Where can I find such a thing?

I had one of these for a while: https://www.amazon.com/Wilson-Electronics-Signal-Booster-Off... Worked well enough. Looks like 4G models are more expensive. (No longer need it as I'm with Republic Wireless now.)


Most cell providers will give you one for a deposit. I know tmobile does for something like $25.

Ironically the booster that T-Mobile provides causes more issues. Unlike the old ones that brought the signal in from an antenna to the base using some coax, the current models link up the receiver to the amp using unlicensed 5GHZ. This killed my 802.11ac speeds when I had one.

T-Mobile will now send a full femtocell that uses your ISP's net and broadcasts both WCDMA and LTE. It's much better.

In Australia the carriers sell them. I'd start there.

I believe all 4 of the major US carriers also sell or even just give them away. It's in their best interest for their customers to have good signal coverage in a place they spend a lot of time in.

Although these days, with Wi-Fi calling for voice and Wi-Fi itself for data, the need for these devices is lower and lower.

That, and the automatic door sensors can be quite noisy.

AC Linear Transformers effectively are antennas, that is how they induce current in the tapped windings as far as i understand things.

We have lights with newer electronic ballasts and some with the old magnetic ballasts. If you take the tracer part of https://www.amazon.com//dp/B0042VII7A/ you have to be within a few inches to pick up the electronic ballasts. You can pickup the magnetic ones from 10-20 feet away.

(We have the LED's to replace them but finding times to do so is a problem.)

It's usually electronic ballasts that cause more interference since they have an oscillator that runs in the high kHz/MHz, while the magnetic ones don't oscillate at more than the 50/60Hz mains frequency.

Same thing happened to me recently! :)

Call in a couple of ham radio operators who like to foxhunt and they should be able to point you in the general direction of the problem within minutes. If the effects are as localized as they say it should be able to be pinpointed within an hour.

I'm a licensed HAM operator.

I would start with just listening broadband with an SDR for a while, just to see what's really going on. Something ought to become visible in the spectrum, at least intermittently.

Once you get the pattern, you could simply move around and measure the relative intensities, map the numbers, and the epicenter ought to become more or less obvious. Then close in with the SDR, watching the levels on the screen, and hopefully you will walk right into the culprit.

An RTL-SDR is a few bucks on Amazon. The software is free. The only other thing you need is a laptop.

For those who need a more concrete example here is a guy who found a power pole that was malfuctioning doing just that, with an odroid, 5x rtl-sdr dongles, and a gps acquisition device.


More info:


Would work just fine with a single dongle, a laptop, and a usb gps device or cell phone, just would have to do a few more drive arounds in different frequency bands.

Can you write this up please - I have lived my whole life with these mysterious radio wave thingamijigs suffusing my world and ... I just don't know how to detect them. TV signals get fuzzy, my loudspeaker crackles just before my phone rings, but being able to deliberately reach out and map them seems almost like magic.


They sell a fancy dongle that works 'better' than an off the shelf model but this $10 model will work just fine for learning: https://www.aliexpress.com/item/USB-2-0-Software-Radio-DVB-T...

If you can, I'd suggest spending a little more on either an RTL-SDR with a built-in upconverter (~$30 on AliExpress) or an SDRplay RSP1A ($120 from Ham Radio Outlet). An upconverter allows the RTL-SDR to operate in the crucial bands below 30MHz; the SDRplay RSP1A has vastly better performance and will pick up all sorts of signals that an RTL-SDR won't. The RTL-SDR is a really cool and very cheap introduction to radio, but I think you might outgrow it fairly quickly if you're technically-minded and have a serious interest in radio.

I'd also suggest seriously considering getting an amateur radio license. It isn't difficult or expensive in most countries, you'll learn a lot about radio in the process and you'll gain the right to transmit on a wide range of frequencies. The /r/amateurradio wiki is a useful starting point.




You don't need an upconverter to receive HF on the version shipped by rtl-sdr.com; it supports it via direct sampling mode. I've listened to plenty of shortwave broadcasters and hams using it with a random wire antenna.

I did recently get an rsp1a as an upgrade once I realized how much fun I was having. It seems better at rejecting noise but otherwise isn't that different than my rtl-sdr. I need to get a windows install so I can use sdruno instead of cubicsdr, though.

While the upconverters are nifty if you're not in a pretty rural area or going to do some serious antenna work you'll be heavily limited by conditions at <30Mhz.

+1 on looking at getting a license though. It opens up a whole new world of experimentation and capabilities. Even on 2m I still get a kick covering 80-100mi with our local repeater network.

Seconding this. Get their kit with the dongle and dipole antennas for VHF and UHF, plus optionally an antenna for HF. Just plug it in, make your antennas the right length for the spectrum you want to explore, and fire up SDR# or CubicSDR to see what signals are present.

RTL-SDR Blog R820T2 RTL2832U 1PPM TCXO SMA Software Defined Radio with 2x Telescopic Antennas https://www.amazon.com/dp/B011HVUEME/ref=cm_sw_r_cp_apa_i_gk...

Portable Antenna Bundle with 7M... https://www.amazon.com/dp/B07DPNPK4D?ref=ppx_pop_mob_ap_shar...

In addition to the rtl-sdr site mentioned in a sibling comment, the stuff provided by https://greatscottgadgets.com/ is well worth looking into. I attended his class at Blackhat and it was a blast.

> my loudspeaker crackles just before my phone rings

You can do nothing about it. What you are hearing is the beginning of a GSM transmission. GSM frequencies are well-known to be easily picked up by audio circuitry. Switching to LTE should solve it.

> GSM frequencies are well-known to be easily picked up by audio circuitry. Switching to LTE should solve it.

Hmm? All GSM frequencies are also LTE frequencies.

Quoting from https://bit.ly/2t30lXv:

GSM “buzz” occurs with GSM (TDMA) phones,” he said. “It is when the phone is communicating with the tower on the GSM control channel, which is not power regulated and can be as high 1 watt, depending on the phone model. It is pulsed data bursts and does not happen on the LTE side (the reason CDMA phones remain relatively quiet).”

Phones using GSM standards cause most buzzing. Phones using LTE and CDMA rarely do. GSM networks are less common than they used to be, but are still ubiquitous, and even non-GSM phones may “step down” to other networks for various reasons.

The Motorola iDEN (Nextel) protocol was very GSM-like in some ways, but the reverse control channel was even louder, and the modulation even harsher. A Nextel in the audience was every live sound engineer's nightmare.

You got plenty of good advice, so no need for me to add to it.

But once you get the right gizmo plugged in, and the right app running on the laptop, it's literally as simple as walking around looking at a spectrum graph. Sure, you can do more fancy stuff, but for the basic level that's it.


Specifically, $27ish dollars shipped, and basically the cheapest still reasonable way to get into SDRs. Receive only though, so while you can explore the spectrum below about 1.9ish GHz, you can't play with it

For a more capable model, I would recommend the ADALM PLUTO from analog devices.

It's ~$150 USD (if I remember correctly)and has a range of 385 to 3800 MHz @ 20MHz bandwidth, but a very simple hack increases it to 70 to 6000 MHz range @ 56MHz bandwith. Check here for more info on the hack: https://www.rtl-sdr.com/adalm-pluto-sdr-hack-tune-70-mhz-to-...

Having just switched to an RTL-SDR.com from a myriad of cheap ones, I'll say that yours will get you started but picks up a stack more noise. You'll also want a better antenna.

Yeah, RTL-SDR is surprisingly broadband for it's cost. They're truly a marvel of cost/features.

For those of us who have been on an actual foxhunt, it isn't often the matter of an hour for something of this sort. It is operationally tricky to do this.

only because a good fox will be mobile and not transmitting all the time.

The most difficult club foxhunt I was on, the fox was static but had three 10 dB steps of power and periods of silence. So no.

OP said that the fox would be mobile and not transmitting all the time. You said the fox was static, but had three 10 db steps in power and periods of silence. 10 db steps in power would trick lots of hunters into suspecting mobility and periods of silence is exactly what op said. I can't imagine why something so close would elicit such a dismissive "so no".

I have heard of loose electric pole hardware vibrating in the wind and causing interference in the 400mhz range.

Basically they were looking to see if it was the source, and the guy banged the pole with a hammer, and the banging showed up on the listening station some 20 miles away.

I've had a similar experience making an FM transmitter. I used a small air coil inductor that wasn't well secured to the PCB as part of the resonating circuit. My FM tuner would pick up ambient noise since the small sound vibrations would ever so slightly change the size of the inductor, modulating the frequency. Ceramic capacitors also have this problem. The small metal 'fingers' are susceptible to vibrations which change the plate distances, and thus the capacitance. Use your imagination to think about cases when this might be of interest for certain groups!

aka Microphonics.

The movement must have been diddling a flaky contact, causing sparking.

Most of the hardware on an electric pole should be grounded and the only attachment from the primary wire(s) to the pole is through an insulator or series of insulators.

That said, if there's a bolt on or near the primary, it's possible it worked it's way out and started mechanically vibrating making contact between some induced voltage and ground say.

It might not be the same, but this sounds similar to what happened in Eden, North Carolina recently.

The gambling parlor next door were using jammers to keep "fish table" players from cheating. This was affecting key fobs, car starts, etc. in a pretty big radius around the location.



Hope the FCC comes down on them like a ton of bricks if they find that the casino was using a jammer. Wonder if they even considered whether they could be inadvertently jamming parts of the spectrum used by emergency services with that thing.

>Hope the FCC comes down on them like a ton of bricks

Oh, they will. The FCC do not mess about when it comes to intentional interference.

If they are intelligent they just installed a lot of cheap neon signs :)

I get our point, but this is taking place in Alberta. There the FCC is Farm Credit Canada. Not sure what they'd do about interfering with fobs.

Huh, I hadn't heard of these fish table games before. For anyone else who also hadn't, here's an interesting article on them that explains them: https://waypoint.vice.com/en_us/article/znm8zx/why-cops-are-...

Would be interesting to know how they were cheating.

Looks like maybe they were using some kind of overload device to confuse the machine when it pays out?



Probably by creating current in places there shouldn't supposed to be, fooling the credit counter: https://www.youtube.com/watch?v=1LfluP0Ygcg

Electronics are such a hassle.

In Lille, France, the automated guided «metro» public transport VAL206[0] is known to block openning of some cars brands.

As it's aerial, in some places it's above ground with, you guessed it, car parks below it.

The tow trucks make a killing with it because you (or your insurance...) pay a full towing charge but your car only need to be towed like 5m for it to open again.

Funnily enough, the RF interference does not prevent closing of the cars, only opening :)


Do people not understand how to use the dead-battery mode of their fob?

I don't think people know that their fob has metal key and the car has a metal lock generally behind the door handle that you can slide in and open normally.

This does not start the car. Starting is a fairly important step.

Keyless start cars (e.g. Volkswagen) have a way to start with a dead fob.

If you hold the dead fob against the little key symbol on the steering column it'll power the fob by induction and you'll be able to start the car.

You're right, older fobs that just do keyless entry may not be able to start the car though.

It will, as most car key fobs also have a RFID in them that the car can read close range (e.g inserted)

It may not start the car, but will it at least let you put the car in neutral?

The poster a couple levels up said people where paying full towing price to have cars moved 5m. If you can put the car in neutral you should be able to push it that far yourself.

Not all cars are automatic. You might need to get hold of a hand instead.

Huh ? It's even simpler to put a manual car in neutral without the key. You could even push start it.

The main problem would be having a locked driving wheel (common in France), which may make pushing it 5 meters away impractical/impossible without lifting the front wheels.

I will do my best never to make a joke on HN again.

Not all cars. Audi certainly doesn’t.

They certainly do. The 3-4 different Audis I have driven all have key cylinders in the door handles and a physical key in the keyfob. And you can start the engine when the keyfob is out of battery because they have a passive RFID built in the fob that the car can communicate with when the keyfob is inserted in the slot in the dashboard.

Few car owners read the manual, and most people don’t know how to troubleshoot.

Probably doesn't help much when the manual is in the glove box of a locked car.

Ideally one would read it beforehand and memorize the important emergency stuff, like what to do when your key fob doesn’t work.

Ideally. But it is a funny image.

And there is something to be said for not being that guy who says "should have read the manual!" when another human being, however flawed, gets stuck in a situation they don't know their way out of.

Absolutely. I’m mostly pointing out that people don’t do this.

It seems like it would be worthwhile for the industry to come up with a standard symbol for “hold your key fob here to make it work when the battery is dead” and print it on the appropriate spot on the car.

That's what smart phones and Google are for. Saved me once.

I once had to be towed because the key stopped working. This was a Smart Roadster (still the greatest car I ever had, nonewithstanding). A battery change didn’t work and the mechanics sent me 100km to get the spare key.

So there are definitely circumstances where the phi’s always artifact alone just isn’t enough to start the car, only to get in.

Don't know how universal it is, but my keyless car has separate failsafe for entry and start. To get into the car, you can slide the physical key out. To start the car, you use the fob to push the start button which I understand to use a passive circuit similar to credit card tap.

At both of the cars that used a fob the salesperson demoed it before we left.

Interference can be a funny thing. We have several of these outdoor LEDs at home:


If I transmit with a two meter ham radio handheld near any of them at night, the light turns off! When I stop transmitting, the light comes back on.

I haven't taken any time to troubleshoot this, but it would be interesting to learn just why a two meter signal makes the light turn off.

You're overloading some "fused" or protected circuit in the little lights with voltage where there's not expected to be voltage. After you stop transmitting, it stops protecting itself.

speaking about interference : moved my home office to a new spot in the house the other day ago - which has 3 LED light bulbs for light in the space.

Turned on the ham radio - in scan mode - picked up someone talking, but noticed a bunch of static also being picked up. Didn't think much of it until I turned off the lights and the static went away. radio antenna was about 4 feet away from 2 diff bulbs (!).

These things are noisy ..thinking about trying a few diff brands to see if there is a difference.

also thinking about borrowing a buddy's spectrum analyzer to see if I can isolate the frequencies of the noise, might be able to put a a filter on the antenna.

There are serious RF interference problems with some LED, CFL lights and dimmer products. Even low power (5W) lights can swamp the spectrum badly enough to jam out DAB and FM radio receivers.

[1] http://www.ledbenchmark.com/faq/LED-interference-issues.html

I wish the FCC would crack down. These devices are in violation of Part 15.

Also from some monitors and TVs. My Samsung monitor spews all across the 1.25 meter ham band. The form of the interference is a serious of regularly spaced narrow spikes across the whole band.

You might try adding snap-on ferrite beads to the power cord. If the monitor has an external switching power supply you could try replacing it; some of those are noisy. Otherwise, if it's an older monitor, the noise is probably coming from the CCFL power inverter (an internal AC power supply that powers the fluorescent backlight.) New monitors usually use LED backlighting.

Yes, I just installed new LED headlights in my car[0], and my FM radio gets staticy when I turn them on.

[0] https://www.amazon.com/gp/product/B07D3H1HWL

There is a lot of information available about this problem and how to solve it. Read this for starters [1]. The cause is the LED "driver" (power supply) and power cables; the PWM supply is making your LED power cables radiate RF energy.

[1] https://betterautomotivelighting.com/2014/12/31/how-to-remov...

I recall seeing a garage door manufacturer selling LED bulbs for $15 or $20 that don’t interfere with openers.

Personally, I’d just cover the bulb in a few layers of grounded chicken wire. But I’m cheap like that.

"Personally, I’d just cover the bulb in a few layers of grounded chicken wire. But I’m cheap like that."

Shielding the bulb won't help when the switching PS in the bulb is making the house wiring resonate. RFI problems frequently fail to yield to silver bullet solutions.

You may try to wind a few rounds of the AC wires to the LED bulb on a ferrite core. That may (or may not) reduce RF bleed through AC.

(shrug) RF is hard.

Yeah, my big plasma TV makes a heck of a lot of noise in the 70 cm band. I need to keep the rubberducky antenna far from it if I want to be able to receive anything.

Also, I've replaced the headlights on my car with LEDs. Much better visibility now, but the FM radio performs much worse. I'll have to figure something out, it's annoying.

For a room where you have radio equipment, I'd either install regular old incandescent bulbs, or DIY some LED strips driven by a constant-current linear voltage regulator (efficiency of the latter kinda negates the point of having LEDs though).



"After investigation it was determined that there was faulty consumer electronic equipment stuck in transmit mode in the area, which was causing the interference. ... In this case, it was determined that it was a remote car starter. It has since been deactivated and the interference has stopped ..."

I wonder whether the atmospheric conditions have some unknown effect on certain types of electronics, especially detectors of photons of any kind, preventing them from working as intended.

Story time: a few years ago I used to work in a building which was intended for many more workers than we actually were there (some floors were completely empty). The garage was big and had parking places for a lot of us, but we were only given a few electrionic keys for the garage door. A lot of us, including me, came to work by bus, so basically there were parking places for all of those who came by car, yet we only had like 10 keys for 20-25 people.

We knew that the keys were easy to disassemble and reassemble, so we devised a solution: using arduino, we created a device that (via a cheap prepaid SIM card) was capable of receiving phone calls, and when any of our numbers called the device, an actuator pressed the internal components of the electronic key. Pointing this device to a window near the garage door was good enough. So, every morning, people called the number of the device, and just by doing that, the door would open automatically.

The thing is: it always worked at the evening, between 16 and 18h. But in the mornings, and especially in cloudy or misty mornings, sometimes it wouldn't work. We tried to investigate but we never knew why this was.

I wonder if a similar phenomenon is happening here.

> I wonder whether the atmospheric conditions have some unknown effect on certain types of electronics, especially detectors of photons of any kind, preventing them from working as intended.

Well, atmospheric conditions have pretty well known effects on electromagnetic transmissions; the presence of water, particularly, interferes with (both scaterring and attenuating) signals that would transmit well through dry air.

I'm confused - I submitted this story and identical link a day earlier but got no traction. Not complaining, just wondering how Hacker News works.


It's like when you tell a joke: who posts a link and when is as important as the content of the link itself. It's unfair, but any human system is influenced that way.

Probably just timing & competition from other articles... Often an article is submitted twice, and the second attempt gains traction.

Portable spectrum analyzers capable of up to 2500 MHz are not so expensive these days. I'd bring a horn antenna and spectrum analyzer and start hunting.

For wireless debugging we use an older tool called the wi-spy dbx. We also have a USRP B200 and LimeSDR mini which have been helpful tracking down interference.

Here's a plot from when we discovered LED motion sensing lights use a radar signal on the upper end of 5Ghz. Every vertical line is another light. You can imagine a hallway filled with 20+.


You probably need more than one analyzer to find the physical location of the signal within a reasonable amount of time. Make friends with local ham radio operators. Almost everyone loves a good fox hunt.


North American cars generally use 315 MHz for the key fobs AFAIK, seems like a hobbyist with an SDR + directional antenna could help clear this one up.

Yes it seems like they haven't gone far enough afield to deal with this; electricians aren't really equipped to deal with RF problems and if the 'Ministry of Innovation, Science and Economic Development' actually employ any token technicians among all their lawyers it will probably still be a long wait unless someone in Carstairs has pull.

Carstairs is 60 km north of Calgary where you find the Calgary Amateur Radio Association (mission: "Have Fun and Serve our Community"), University of Calgary Amateur Radio Club and other organizations, all of whom would be thrilled to break out their spectrum analyzers and nail this to the wall for free.

If it’s a harmonic of a lower frequency, one could try dialing in 105MHz into an analog-tuned FM radio and seeing if there’s anything odd coming through.

I’ve used this for assessing some harmonics of 4-5 MHz clock lines causing issues.

USB interface SDRs and spectrum analyzers capable of up to only around 1000 MHz are really cheap now.


At 315Mhz you might even be able to do it with a $10 RTL-SDR.

I've captured my BMW's key fob signal with one of the cheapo RTL-SDR devices. The little noolectric I've got has worked great.

Would a quality software defined radio (HackRF) and a directional antenna be sufficient?

Given the leaps and bounds of development in this area recently, I wouldn't call HackRF a go-to device anymore (compared to the more recent devices) but yes- any of them totally would be able to pick this up.

I've been planning on buying HackRF in the coming months so I'm wondering what better devices are there. Do you recommend another SDR device instead?

If you don't need transmit capability, the SDRplay RSP1A has phenomenal receive performance for the price. If you do need to generate signals (and you understand your legal obligations), the Red Pitaya, LimeSDR and bladeRF are worthy alternatives to the HackRF.

The Red Pitaya is a particularly compelling alternative from a hardware hacker's perspective, because it does double duty as an extremely versatile measurement and data acquisition device.

The HackRF is a solid, if slightly dated SDR platform. There are plenty of better SDRs out there, but none of them are as ubiquitous and well documented/supported, particularly in the hobbyist space. And none of the better specs of other SDRs matter that much unless you need them, and you'd probably know if you do.

If you're just getting into SDR, I would just get a $20 RTL-SDR, and then move on to something like the HackRF or BladeRF later.

What's considered "go to" now?

LimeSDR, BladeRF, AirSpy... The first two are capable of emulating base stations - quite incredible. AirSpy is RX only but has incredible bandwidth and a very clean signal

FYI they make a Mini Lime SDR for even cheaper! https://www.crowdsupply.com/lime-micro/limesdr-mini

been lusting after one of the little guys for some time now.

Yeah, but the Mini has half the sample rate AND half the channels. That's a quarter of the capability for half the price.

I'm also kind of salty that they dropped the MicroUSB variant of the full-size model. The Mini makes sense to have it a "stick" format, the full one does not. The full one having an A connector on it has been nonsense from day one.

I still will probably end up buying one because they're still the best bang for the buck.

Directional stuff can be tricky.

Just use a rubberducky antenna (a stick - heck, just a piece of wire), and measure relative intensities in a few points on the map. That will give you an idea where the epicenter is.

Then walk through that area while keeping an eye on the intensity. I betcha you will bump right into the culprit.

Geez, that would suggest a massive amount of noise or deliberate jamming on either or both 315 and 433.92 MHz, a mass delusion or something like helium wrecking the clock circuit. We should send Dave from EEVblog and Thunderf00t to investigate. ;)

It sounds like all they've done to try to isolate the source of interference is shut off the power to the nearest store. This probably shouldn't be a national story until they look a little harder and can't figure it out...

It sounds like they've brought in IC (Canadian version of FCC) to investigate the interference. As for the news story, I guess they think they'll know the answer soon so this is just a teaser so they can get everyone's clicks again with a second story that answers it.

We had problems with Ford / lincoln in our parking lots. Idiots (car manufacturers) are using a bands in the 800mhz to 900mhz range. We paid about 60,000 in towning fees before we swapped our digital sign board systems out.

It's very likely one of two things - either the RFID Anti-Theft device the store has, or an automatic door opener, both can cause spurious emissions in the band that keyfobs use.

My car fob has never worked in the parking lot near the top of San Bruno Mountain just south of SF. I've assumed the proximity to Radio Peak is the culprit.

Yup, also Twin Peaks near Sutro Tower. "Dead battery," mode doesn't work for me either. So much fun.

Daaaang, that's got to be some power. I've looked at Sutro's architecture from across the bay, but never got up close to see what's on it.

I have a keyless-only car now, and this sort of stuff worries me. "Dead battery" mode has always saved me thus far, but in that situation? I'd be hosed. Can't even put it in neutral and coast down the mountain. (Electronic transmission, there's no shift-interlock bypass...)

I think their problem is in calling electricians. Wrong specialty..

I had an interesting experience a couple of weeks ago. I woke up in the morning and found that my phone is almost completely drained while it was plugged into the outlet all night. I then tried another outlet and after another no-go I checked to make sure I have electricity, which I did. I ended up restarting the phone and it magically started charging again. I thought nothing of it until that same morning I got to my car and was unable to unlock it via key fob. However, it started working again when I tried it at my work's parking lot. Maybe just a coincidence.

I could see in a future where most cars are FOBs using a weaponized interference to prevent people from accessing their cars. An authoritarian regime might really enjoy that capability.

Or enemies who've spent the last decade systematically building a library of vulnerabilities and footholds in tons of (government and consumer) infrastructure.

Did you read the Valasek/Miller paper on the Jeep hack? For me, the technical details were all well and good, but the most interesting bit was right in the intrioduction -- Their research was funded by DARPA.

Wait, what?

Consider this: Everyone knows that water supplies and power grids are critical infrastructure. Bridges and tunnels, too. Transit, obviously -- an attack on the NYC subways would cripple the city. That's all understood and appropriately protected.

But imagine an attack that caused 10% of the cars on the road right now to simply turn off, and not turn on again. Some folks would pull to the side, but a lot wouldn't, and the roads would be an obstacle course for quite some time, while every tow truck scrambled to clear them. In my mind, that's just as crippling as shutting down a subway or an airport.

Individual vehicles haven't been thought of as critical infrastructure in the past, because they weren't vulnerable to that sort of attack. But they're becoming so, and in the most haphazard, security-what-security, if-it-compiles-ship-it, sort of way. And I think DARPA's goal in sponsoring this sort of research is to force people to realize that.

Because you bet the bad guys already know it.

with just about every car component now being computerized and thus prone to being backdoor'd I don't even think they would need to go that far

Wireless-controlled shopping trolleys (that put the brakes on if they're taken outside the supermarket's property) causing radio interference?

Those are actually controlled by magnet strips in the floor.

This happens to my car in the morning only. Not at night. Its flappin weird.

It's coming from some equipment that get turned off at night.

If the signal is relatively constant, triangulation is fairly straightforward. Hold the receiver against your chest and slowly turn in a circle. When you find the minimum, the source is behind you and your body is blocking the signal. Draw a line on a map, move to another location, and repeat.

You can do this with a $26 antenna on a $25 RTLSDR on a $5 OTG cable plugged into any random Android phone. It takes a minute to install the spectrum analyzer app, probably two minutes to plug everything together, and about a minute per "reading". The rest of your time is spent driving.

This is a massively fun hobby I would encourage anyone reading this to consider. Start at the rtl-sdr.com blog and read some archives, there's a ludicrous amount of stuff within the reach of this incredibly cheap receiver.

I guess having only 1% of the e-commerce market in China has a bright side.

They should have called a HAM

Maybe someone can bring this same technology to San Francisco and other crowded urban areas. It's endlessly annoying that every car lock/unlock these days has to be accompanied by a HONK.

Yes! As someone coming from Europe to the United States, I am always puzzled by how the country seems to be completely insensitive to noise. The honking cars are a good example: this is really rare where I come from. Yes, cars sometimes do make sounds when you press the button a second time, but those are chirps, rather than full horn honks.

In the US, I've rented cars that sound the main horn every time you lock the car. Bizarre.

I just disconnected my horn. Has the nice side effect of stopping me from rage beeping at idiots too! I hated having a loud honk in residential areas late at night.

I was thinking I might connect the 12V for the horn to the ACC, so it can only beeps when ignition is on, but I haven't got around to that yet.

You'll want to be sure to check your local laws before doing that. Most (maybe all?) US states require a working horn for safety reasons. Here, for example, is Minnesota: https://www.revisor.mn.gov/statutes/cite/169.68

I live in New Zealand, so no US state or federal laws apply (unless I get extradited?)

Yes, it is a legal requirement, which in practice could void an insurance claim, or a criminal case if I hurt someone, but sometimes you just have to make a choice.

> Every motor vehicle when operated upon a highway

At least if OP follows through on running his car through his key, he'll be safe. (How about using a relay attached to something that's powered during key-on?)

It's a legit use of the horn to make some noise when another driver can't see you and is about to collide with you. (Honest mistake that happens to a lot of people, the horn should be seen as non-judgmental in that case.)

I was actually able to disable this in my GMC, but now I find myself double and triple checking to make sure it locked.

It's not clear to me why the clicker can't beep to confirm instead of the car itself!

I guess it's just for finding your car in big parking lots? Seems like a different button could be dedicated for that far less common use case.

That's simply because these remote controls are transmit-only, fire-and-forget devices which spew out a pseudo-random code to the receiver without being able to listen to any response. This is also why you should not click the button on the remote too often (as in 'more than 255 times') when not in range of the car as that gets the transmitter (key) and receiver (car) pseudo-random generators out of sync - the receiver accepts a sliding window of 256 random codes as valid. There might be different implementations of this feature using key fobs but this describes the majority of them.

That requires the car to communicate back to the clicker, which is more difficult/expensive, and can fail even if the car did successfully lock.

It's certainly possible though, these are usually called "2 way remotes": https://www.compustar.com/what-is-2-way/

In my car, the headlights and park lights flash once on every lock. No beep needed.

AFAIK the fob is normally just a transmitter, so this would require it to also have a receiver in addition to a buzzer and other circuitry. I imagine that could significantly reduce the battery life.

The solution you propose requires 2-way communication with the car. Virtually no cars do this (in their OEM configuration anyway.)

Without 2-way communication, the remote has no way of knowing if the vehicle acted on the signal.

I think the clicker can only send, not receive

Same on my VW, but the preferences are per key fob. Surprised me the first few times when I used the spare.

Without that honk I'd still be stuck in a parking garage in Atlantic City wandering around looking for my car.

Weird, cars don’t honk in Germany when we lock them. We don’t tend to lose our cars. The blinking lights are more than sufficient.

i would guess parking lots in us are much bigger than in Europe

A couple times when I worked for a very large company, with an ocean of cars in the lot, I had to resort to hitting the open trunk button and walking around looking for that.

If there's nobody around you can hit the panic button too.

Didn't you want to become famous like this guy?


Take a photo of your cars location and parking level info with your phone.

Some airport parking garages will tell you where your car is parked when you pay at the kiosk. With license plate scanners and a vehicle scanning all the plates periodically..


Google Maps has a nice feature now where it offers to remember your parking location at the end of a journey. Handy if you're in a new area.

That requires remembering to do so beforehand, though.

A bad experience does the job.

Cars have been locking with honks when you double press the lock button ...forever

The honk is not the car locking, it's the alarm engaging as it usually comes from the alarm horn. Most cars with no alarm system don't make more than the mechanical sound of locking the car and the visual aid of the signal lights blinking.

There are some cars that use the car (not alarm) horn when locking so maybe their central locking system is connected to it, although it never looked like a factory option, rather an OEM alarm or something similar.

I have never seen a car that doesn't honk when you lock it, alarm system or not (and I rarely see cars with alarm systems around here). Maybe this is a regional difference. Do you live in North America?

The "honk on lock" thing does seem to be a North American thing. I would always be startled and annoyed when locking my rental car in the US.

I haven't noticed cars anywhere else doing this, but I'm not that well traveled.

In the UK it's illegal to sound the horn when the vehicle is stationary, or between 23:30 and 07:00 in a built-up area, so someone who brought one of these auto-honking US vehicles to the UK would have to lock it by some other means?

A quick reading of the rule seems to imply that it only applies on roads, not for example in your driveway or a parking lot.

See: http://www.legislation.gov.uk/uksi/1986/1078/regulation/99/m... , https://www.legislation.gov.uk/ukpga/1972/20/section/196/ena...

FWIW a lot of UK cars are parked on the street at night, rather than on private land.

https://www.racfoundation.org/motoring-faqs/mobility#a6 suggests it's about 35% of vehicles in large settlements.

I turned mine off in my Dodge Caravan after owning it for a day. It was pretty easy to find in the settings. The lights flashing are enough feedback for me.

Europe. Making the horn sound seems excessive compared to just flashing lights. Perhaps some regulation in Europe discourages manufacturers from using anything that causes unneeded disturbance.

It's a light honk, here's an example: https://youtu.be/_rpEtxBo00U?t=23

I don't find it too bothersome, but maybe I'm just used to it. In some other videos people are suggesting that it can be disabled on most vehicles by holding the lock and unlock buttons simultaneously for 2 seconds.

> There are some cars that use the car (not alarm) horn when locking

Every GM vehicle I have ever owned honks (via the car's horns) on the 2nd lock.

(a) there is not a seperate alarm horn (b) removing the horn, also disables the 2nd lock honk.

I don't think power locks were standard until roughly the early 90's. Same with those completely useless "alarms".

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