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Comment Re: AM radio is nothing in terms of volts. (Score 1) 313

Yes but the argument that all those measures add cost and weight is still valid.

Not enough weight to meaningfully affect range, though. A few extra ounces is margin-of-error stuff when the car weighs two tons.

Whether it is phase cancellation (which would require a redesign, still have lots of noise harmonics and consume more power) or shielding.

Sure. Anything you do will consume more power. But a more complicated radio circuit with a differential amplifier that probably draws just milliwatts more power would once again be completely lost in the noise when compared with a self-driving computer that consumes two or three hundred watts continuously, and adding a couple more loop antennas right next to the drive motors would likely add just ounces to the vehicle's weight.

The point is that this doesn't necessarily have to involve some thick metal shield that adds a hundred pounds, and nobody is going to complain because the vehicle's maximum range drops by ten or fifteen feet.

Moving the antenna isnâ(TM)t an option since the motors are in each corner of the car for most EV.

No, they're actually in the middle underneath the car, typically. EVs almost always have two electric drive motors, not four. (CyberTruck has an option for three motors.) With antennas on top, that's a heck of a lot of metal between you and the noise source.

Comment Re: Good Grief (Score 1) 228

It is possible if both parents don't have to go to work.

It is not, not even then. You'd need at least three parents: One to go to work, one to stay with the kid, one to cover for the second when they have to do something other than watching the kid (clean the house, do the laundry, use the bathroom, etc.). Oh, sure, you can try to put the kid in a safe environment while you do stuff, but many young children are shockingly good at finding ways to get into stuff they're not supposed to get into, and do it far faster than you would expect.

A team of nannies can do it.

People used to literally be with their children all day for the first few years of their lives. They didn't want them to wander off into the woods and get eaten by a wildcat or whatever.

People used to live in the middle of a village of other people who watched out for their neighbors' kids when their parents had to take their eyes off of them. And kids used to die. A lot. Far more than we'd consider acceptable today.

Comment Re:Young kids are smarter than you think (Score 1) 228

"are by people who don't have kids"

Absolutely this. Until someone has had kids or at least looked after some for a long period of time they really have no idea.

And not just one. KIds vary widely and it's not uncommon for parents who've only dealt with a single child to assume that all kids are like that one. Usually adding a second kid is enough to open their eyes when they realize that none of what worked on the first kid works with the second and vice versa. Occasionally parents get two that are very similar and don't learn this until they have a third, or until grandkids come along, or other close exposure.

Comment Re:More technoligcal solutions (Score 1) 228

Kids can definitely be taught to not stick non-food-items in their mouths. If kids are being monitored when they are small and taught what is and is not safe, they carry that forward and you don't have to keep as tight a reign on them.

Source: I'm a dad.

How many children have you raised? I'll bet, one. One who happened to be easy to dissuade from putting stuff in their mouth, so you have extrapolated from that sample of one to all kids everywhere.

The fact is that kids aren't all the same. Some are easy to train, some aren't.

Source: I'm a father (4X) and a grandfather. Based on my sample, I should perhaps assert that all babies and toddlers stick everything in their mouths and there's nothing you can do to teach them otherwise until they're at least two, and usually three. But I know that kids are all very different, and so I can imagine that there may be some child who can be taught not to put stuff in their mouth younger than that.

Comment Re:Actually (Score 1) 98

Importing a H1B worker, even if paid the same as a US worker is not the same.

Certainly there are differences, I was addressing pay.

One prefatory comment before I respond to the rest: I am in no way claiming that H1-Bs aren't terribly abused by many companies. I know they are; I've seen it firsthand (before joining Google). But the context of this discussion is Google, and in nearly 15 years at Google, many of them as a manager, including of H1-B holders, I have never seen any abusive behavior. Moreover, no one I know had seen or heard of any, nor would they stand for it.

If I or any other manager -- or individual -- thought that an employee was being taken advantage of for their visa status, and spoke up about it, the complaint would be taken very seriously. This has become even more true since the DEI initiatives.

Refuse to work 99 hours a week, you will be eventually let go and deported.

No one at Google is required to work anywhere near that much, and the expectations for US citizens and H1-B visa holders are the same. 40-45 hour work weeks are the norm. Some people decide they want to work a lot more for personal reasons, or because they think it will help them get promoted (they're not wrong). Management typically verbally discourages but in practice rewards long hours.

I did that. I had a report that worked way too much. I regularly told him it wasn't healthy and he should slow down... but when it came to review time and promotion time his productivity and impact were outstanding, so he got outstanding reviews and quickly got promoted. He's now my peer and I wouldn't be surprised if he's eventually my boss, which I'd be okay with. He's a hard charger, but a good guy.

File a labor complaint, you will be eventually let go and deported.

This also doesn't happen at Google. I have personal knowledge of an H1-B visa holder who filed a complaint with HR. Their complaint was acted on and they were not punished in any way.

Take too many vacation days, you will eventually be let go and deported.

I suppose. I've never seen anyone (citizen or not) let go for taking too many vacation days. It would definitely not happen unless they actually exceeded their allowed vacation time by more than the allowed amount (you can go one week negative). And I've never seen anyone do that. There's really no need to; the vacation is pretty generous and if you want to do something like go hike across Australia for six months you can generally get a leave of absence (unpaid) to do it.

Also, employees (regardless of visa status) are encouraged to use all of their vacation time. Performance reviews are calibrated against days worked so theoretically taking time off doesn't hurt you. In practice it can a little if your'e really gung ho for moving up the ladder, not because anyone explicitly penalizes you but because always being available makes it easier to take advantage of the opportunities to have great impact. But, again, none of this is any different for citizens vs non-citizens.

Complain about work assignments, you will eventually be let go and deported.

Never seen that. Complaints about work assignments in general are really rare. Google SWEs have a lot of input into what they work on, and it's pretty easy to change teams if there's nothing in your team's area that interests you.

There are some definite downsides to the bottom-up decisionmaking culture at Google; many of the dead products are directly attributable to this quirk of the company. Products get started by SWEs who think it's a good idea and manage to convince enough others around the company, so management assigns headcount to it and engineers join the product, build it out and launch it. Then if it doesn't immediately get traction (read: millions of daily users with a trajectory towards hundreds of millions) it stagnates, SWEs migrate away to projects with better growth prospects, the product becomes a maintenance burden that it's hard to keep staffed, HC is cut, then eventually the product is discontinued. Companies with top-down decisionmaking culture start with executive champions who keep them funded and growing long-term, and in that sort of culture you can just assign people to do the maintenance and that's that.

Anyway, the point is that work assignment complaints don't happen much. And to the degree they do, there's no difference in how it's handled with citizens vs non-citizens.

And the pay is US equivalent but at the low low end of the range for the job title and salary band.

Nope, that is definitely not the case at Google.

Promotions and wage increases will be below average as well.

Also absolutely does not happen at Google. Citizenship status or visa type has absolutely no bearing on any of that.

The biggest problem I've seen for H1-B visa holders at Google is that sometimes the government doesn't allow them to renew. In that case, what usually happens is if there's a Google office in their home country they relocate there (with applicable pay adjustment, but with a generous relocation package) where they stay for a year until they can qualify for an L-1 visa, then they move back (again with applicable pay adjustment and relocation). If there isn't a Google office in their home country, Google looks for another country where there is an office and to which they can go. The UK is apparently pretty easy, so that's a common destination. Again, they stay there for a year until they can qualify for an L-1, then they return to the US. Unless they'd rather not, of course, but they usually do.

Obviously, not everyone wants to do this "one year somewhere else" dance, so sometimes they separate. That happened to a guy on my team just a few months ago. He decided instead that with what he'd made working for Google in the bay area he could afford to take a few years off living in his home country of Vietnam, so he just quit and went home rather than move to the UK. Big loss for the team, actually. He was a brilliant engineer.

Comment Re:Here we go again (Score 1) 98

Why would you lie when that's so easily fact-checked, and do so without at least posting as AC while you're trolling?

Google's pay rate for a level 4 engineer in India is about 6.7m rupees which is roughly 80k USD. In California the same category averages around 280k USD.

We're talking about H1-Bs, which means they're in the US, not in India. Don't be an asshole.

Comment Re: AM radio is nothing in terms of volts. (Score 1) 313

You're assuming that they need to actually control the noise.

True. The text of the bill says nothing about harmful interference. However, there is the implication that the receivers being mandated might actually work, and not just for the vehicle operator, but for the vehicle in the next lane as well.

The vehicles in the next lane can always slow down or speed up or change lanes to move away from your car if your car makes its radio too noisy, so that's likely to be a non-issue. I haven't measured the field strength from an EV to see if it exceeds those limits, though, so I could be wrong.

Note that the FCC allows AM transmitters up to 1705 kHz under section 15.219 without a license as long as the ERP is below 100 milliwatts and the antenna is no more than 10 feet tall. There's no transmitting antenna in an EV, so as long as the ERP is below 100 mW, presumably that qualifies. For frequencies above that limit, section 15.223(a) gives you a field strength exception, and given that we're talking about wideband noise, presumably no stricter narrowband limit should apply, so the limit is likely 100 microvolts/meter at a distance of 30 meters, which is, I think, in the neighborhood of 200 mW ERP. The stricter limits under section 15.209 presumably do not apply because it is not an intentional radiator.

That said, there may be additional rules that I don't know about, so take that with a grain of salt.

Comment Re:AM radio is nothing in terms of volts. (Score 1) 313

AM Radio is absolutely nothing in terms of vaults, because you can literally run one off of a AA battery for hours.

This has nothing to do with saving money. Because when they build these things en-masse and buy them from a supplier that's already making them, they're probably already cheaper than they could build themselves And it wouldn't even add a dollar or so to the cost of the car.

I wouldn't say the cost is quite that low. Modern head units are all digital, so you have to take into account the cost of adc circuitry and integrating it with the software stack. Between that and antenna considerations, it does carry an additional (though negligible) engineering burden.

Either the FM radio in the car is analog or it is doing some sort of software-defined radio thing, but either way, analog-to-digital conversion is still effectively occurring in the radio circuitry already, which means that could be done for AM just as easily. So that part of the cost should be quite close to zero beyond the cost of the AM receiver circuit itself (and for SDR, it would probably be exactly zero).

The real question is whether an AM tuner can usefully function with that much environmental noise, or whether you need to come up with something significantly more complex in terms of the antenna(s), demodulator(s), etc. It's the frequency and the modulation that make it problematic, not the analog nature of the signal, because notwithstanding the existence of HD Radio, a large percentage of FM is analog, too.

Comment Re: AM radio is nothing in terms of volts. (Score 5, Interesting) 313

Yeah saying it would affect ev range is hilarious straight up lying.

No, they're not.

Controlling RF noise is hard. Especially when you're switching enough current to accelerate your four ton electric tank from 0-60 in 4-something seconds while you're saving the planet or whatever.

You're assuming that they need to actually control the noise. Strictly speaking, I'm not sure that's a safe assumption. The only absolute requirement is that the radio must reject enough of the noise go get a usable signal. Whether that happens by the car having more shielding, by putting the antenna farther away from the source of noise, or through the radio being more capable of rejecting outside interference is an implementation decision.

Some other approaches might include:

  • Phase cancellation. You know exactly what signal is going into those motors, and you can presumably compute the harmonics that get added as it goes through the windings or whatever. Invert the phase, cut the amplitude down a lot, and sum with the (probably slightly delayed) analog signal before demodulating.
  • Using multiple antennas with beamforming, creating constructive interference in signals coming from the direction of the desired AM station (with the direction adjusted continuously as the car turns) and destructive interference in signals coming from the directions of various noise sources.
  • Putting the antenna on top of the car so that the entire body of the car is between it and the noise.
  • All of the above using some insane LLM-based software-defined radio monstrosity, where the actual demodulation process itself is taking data from multiple inputs, using some sort of machine learning to recognize the shape of noise patterns and subtract it from the inputs, etc.

How effective any of those approaches would be is anybody's guess. I'm thinking the last one is probably overkill (and probably wouldn't work anyway), but beyond that...

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