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Am I slowly damaging my 2020 M1 MacBook by charging it with a cheap 5V 1A USB-A to USB-C charger at night? What's the actual risk here?

The actual risk is that a cheap charger fails in an unsafe way, and exposes users to unsafe voltages. You need, internally, the right creepage and clearance distances, and you need to use the correct parts in certain places with the correct failure modes (e.g. must fail open or must fail closed). Some cheap chargers are not built to the same safety standards. You won’t notice anything unless they fail in an unsafe way. Unlikely, but possible.

> You won’t notice anything unless they fail in an unsafe way. Unlikely, but possible.

Cheap chargers skimp on safety. Entirely possible they fail unsafely.

I once bought a cheap no-name Android charger and it literally exploded after a year of use. Hot metal droplet landed on phone screen which was a cute reminder for a while (until later the screen cracked through where the droplet was).

That tingly feeling has been found by me on plenty of different device power supplies. That is high voltage getting passed to the low voltage side - a sign of bad design. The last two devices I remember were (1) a multi-USB charger which tingled but seemed to work okay and (2) cheap speakers for a PC where the voltage hum was causing serious problems with other devices connected to the PC (and hard to diagnose cause).

I'm amazed how many unsafe electrical devices we own: the safety standards are not working in my experience. And I think New Zealand has stronger standards than the US.


> I'm amazed how many unsafe electrical devices we own: the safety standards are not working in my experience.

Safety standards aren't the issue, their enforcement is. In most countries, agencies overseeing the safety of electrical consumer equipment, are perpetually understaffed and/or underfunded.

So they don't have the resources to take a good sampling of what's on the market, and (thoroughly) test those samples.

As a result, it's mostly especially bad gear (discovered by accident, # of incident reports etc) that gets attention. Or becomes subject of a recall.

What's left is relying on paperwork, and manufacturers or importer's integrity. Which (as you note) varies a lot depending on where you look. Especially in this day & age of people buying cheap junk directly from abroad through Ebay, AliExpress & co. Not to mention fakes, or no-name manufacturers that pop up & disappear overnight.


> You won’t notice anything unless they fail in an unsafe way. Unlikely, but possible.

Which, in the worst case, will start a fire that will burn down your house. It's not worth the risk of using cheap chargers; buy from a reputable brand


That's not the only worst-case scenario: You could also die from an electric shock. This actually happens every once in a while with cheap chargers.

And from a reliable retailer that doesn’t sell counterfeits or turn a blind eye like Amazon does. If you buy Apple, get it from the Apple Store or B&H.

Yeah, the reputable chargers aren't even expensive now that we're on USB-C. Knockoffs were a lot more tempting during the MagSafe era.

If anything, the opposite. Most fast charging devices (any that advertises a 0-50% charge rate) end up throttling charge as it gets closer to 100% because filling up all cells super quickly can actually damage the battery.

That's also why many laptops (such as Macbooks) come with an "intelligent" charging feature that will limit charging to 80%, only charging up that last 20% when it thinks you'll need it


On the other hand, ultra-low-power charging might effectively cause alternating between charging and discharging (e.g. when the Macbook wakes up to do things via "power nap" in the background, which on Apple Silicon devices can't be prevented and which might use more than 5W).

Yeah, slower charging (like 20W) seems good, but I've used phone chargers out of desperation before and seen the alternating charge/discharge. Can't be good for it.

Do a search for “cheap charger bricked phone”

The app isn't part of the developer program so when you try to open the app, MacOS says "You should move this app to the trash" haha! Workaround via running: xattr -c /Applications/Marker.app



As someone who switched to a heat pump recently, you should know "your mileage may vary." Don't confuse physical efficiency for cost efficiency. In many places, natural gas is still more cost efficient, even if it isn't as efficient in terms of physics.


As someone who switched four years ago to a heat pump plus conventional furnace, I can state from experience that my thermostat takes electricity cost per kWh and gas cost per therm (other units are available, these are just the ones that match my utility bills) and efficiency of both the heat pump and furnace and runs whichever is cheaper.

Gas cost has varied a bunch over the years I’ve had it, electricity less so. But the furnace has only run a few days per year and only when when it’s been (depending on gas cost) below 10 to -5 degrees Fahrenheit.

My heat pump (trane xv19) kicks ass and if I were doing the hvac upgrade again I’d skip the furnace entirely and let the heat pump work a little harder/longer on the coldest days.

It’s damned near always more cost-efficient to run the heat pump. And my shiny new high efficiency furnace will never, ever pay itself off saving me a few bucks a day the three or four days per year that the math works in its favor.


It really depends on your area's natural gas vs electricity prices, which can vary wildly.

Electricity can range from 11¢/kWh to 29¢/kWh in California or higher: https://www.energybot.com/electricity-rates/

Natural gas ranges from (converted) ~ 2¢/kWh to 8¢/kWh in Florida: https://www.eia.gov/energyexplained/natural-gas/prices.php (using conversion factors from https://www.nrg.com/resources/energy-tools/energy-conversion..., which I think assumes 1000 ft^3 ~= 1 therm ~= 29.3 kWh)

So your heat pump's COP has to exceed the ratio between natural gas and electricity in your area to make it cost-effective (or you can get solar + battery backup).

Electricity prices can vary quite a bit, too... in Cali, for example, it's gone up from 14¢ to 24¢ over 16 years, which is nearly double the rate of inflation.


> As someone who switched four years ago to a heat pump plus conventional furnace, I can state from experience that my thermostat takes electricity cost per kWh and gas cost per therm […]

What is the make and model of the thermostat you are using?

Is it from the heat pump OEM (Trane?) or a third party?


Trane xl1050.

It’s a rebranded Nexia


"Dual Fuel Calculator" on page 15 (§5.3.8):

* https://www.bayareaservice.com/wp-content/uploads/2020/02/18...


Can you give more detail about your system and in particular the thermostat that makes these adjustments? Sounds interesting!


Seconded, I also want to know the model of thermostat they're using!


Heat pump is a Trane XV19 and the thermostat is an xl 1050 (supposedly trane but my understanding is it’s a rebranded Nexia)

The process to update the costs (which has to be done a few times per year when my utility changes their rates) is not very user friendly - have to get into the technician menus and change scary looking stuff) but it works quite well.


> In many places, natural gas is still more cost efficient, even if it isn't as efficient in terms of physics.

As page where you can enter some numbers:

* https://www.heatpumpswork.com/cop-target

Also, given a US zip code, how often the temperature may drop below 15F / -10C (which is a cut-off for many units):

* https://www.heatpumpswork.com/cold-days

A good HVAC contractor will create a design based on your building and location, and it will cover 99% of average days efficiently for heating and cooling:

* https://www.greenbuildingadvisor.com/article/design-temperat...

* https://www.airequipmentcompany.com/2021/what-does-design-da...

For the remaining 1% it will basically have to run all the time to keep up. (In any given year you may not even get below/above the average outlier 1%.)


Natural gas is dirt cheap in most of the U.S., so it does make it hard for heat pumps to compete, especially if electricity is expensive. Just checked my most recent gas bill and I only paid $1.09/therm (plus 7% sales tax and $10 fixed fee).

OTOH if you’re heating with propane or fuel oil, heat pumps are probably a good alternative.


Last year I had to replace my HVAC. I was set on getting a heat pump, being a huge fan of efficiency. I was averaging a $1.05/therm delivered for gas, and about 17.5 cents/kwh for electricity delivered. A therm is about 29 kwh, so I pay the equivalent of $5.07/therm in electricity.

The best whole house air-source heat pumps had a SEER2 of 18.5, or a COP of just under 5.0. I need a COP of over 5 to just break even in terms of cost efficiency. So a heat pump would actually cost me more on an ongoing basis. And the price for a heat pump installation was $10k more than a furnace/AC.

I just couldn't do it. To pay more up front and then ongoing was just too much. If you showed me even a super long range projection of saving money, I would have been down for it, but it just was not there.

If I can get solar on my house it may make sense, I will cross that bridge in a few years as my roof is almost end of life, but that has its own headaches as I have limited space (brownstone, flat roof), and am in a historic district.

Next go around, as heat pump tech improves and hopefully gets cheaper, it will probably make sense, but for me right now, it just didn't work.


Thats kind of high. I only pay $0.78 a therm here in Wisconsin. 1 therm is around 30kwh so im paying like 2.5c a kwh vs 17c for electricity. So unless I can get a CoP of 700% from a air source heatpump im literally lighting money on fire. That really is the main issue, as much as I care about emissions I don't care enough to spend money on a heat pump to then spend more money on utilities. And the calculus gets worse and worse when your poorer.


Looks like Wisconsin has lower than average natgas prices vs. rest of U.S.: https://www.eia.gov/dnav/ng/ng_pri_sum_a_EPG0_PRS_DMcf_m.htm


seems pretty comparable to the other colder parts of the country. (besides the east coast) The warmer parts of the US i'd imagine are less sensitive to residential gas prices.


Gas powered heat pumps also exist, using the same principle as gas powered refrigerators… from what I’ve heard they are already used in some countries but not on in the USA.


They are very likely denigrated as 'obsolete technology', but like all technology there are use-cases where a particular technology works best.


Why they would be obsolete if more efficient than regular natural gas heat, which is by far the currently most widely used home heating technology?


:)

When did you last see a kerosene-powered fridge? It's about 40 years since I last saw one. Hence my 'obsolete technology' label.

Reverse-cycle (heating) heat-pumps rely on fans to extract the heat away from the machine and send warm air into the room. If you have electricity for the fans, you might as well use that electricity to power the heat-pump too.


modern RVs still widely use propane powered absorption refrigeration, although that is starting to move over to solar and battery arrays.

The fans are a tiny part of the energy used by a heat pump, most of the energy is for running the compressor. Electric heat pumps are more efficient and economical than electric heat, but still generally more expensive than gas heat, and impractical compared to gas if that electricity itself is made from gas in the first place.

If you power a heat pump with gas directly, you are effectively getting over 100% efficiency: you keep all of the heat generated from the gas, plus are 'pumping' heat from outside. It's going to be even more economical than regular gas heat, which is already more economical than anything else.


Especially if you get your electricity from PG&E, who charges ridiculously high transmission and distribution fees.

It makes financial sense in a lot of places to switch to solar plus battery for nearly all energy use. Especially if you can charge your EV directly from solar. Heat pumps at night and in the evening need the batteries though.


For how long is gas likely to be cheaper? It’s generally more scarce right? Does anyone have predictions on US price over the next few decades?


Fracking has made natural gas extremely cheap in the U.S over the past several years. Apparently, right now its at the lowest inflation-adjusted price since 1990 per the WSJ: https://archive.is/8wEi7


As gas use declines, prices are likely to stay low. So probably a long time.


I used Obj-C professionally for about 2 years and Swift professionally for about 2 years. I have a slight preference for Swift. I've been doing mobile dev on iOS and Android since 2012 and there have been a lot of language changes and programming paradigm shifts. I think it's become more accessible for new devs. For me, I don't think the time and headache to learn the new ways really had a lot of benefit on the end product. Maybe in larger software shops it did.


Where can someone upload a contract and ask the AI questions about it in a secure and private way? It's my understanding that most people and organizations aren't able to do this because it isn't private.


We do this today (securely upload a file and ask questions or summarize) and part of our promise, and why we're having early success, is because we promise not to train with customer data and we don't run directly on top of OpenAI.

https://casemark.ai


You can try us [1] . During the upload process you can enable data anonymization. It’s not perfect though.

We use open ai but they only get segments of a contract. Not the full one and can’t connect them.

You get the review via email and after you can delete the document and keep the review.

[1] legalreview.ai


ChatGPT enterprise? Or over API. They state that those offerings data is not used for training. I'm not a lawyer but afaik illegally retrieved evidence cannot be used - "exclusionary rule".


You can host your own LLM - something like Mixtral for example - then you have full control over the information you submit to it.


It can still work; just needs a better implementation.


How did you get cian.lol? Why isn't it cian.omg.lol?


You can register domains yourself and set them up, under "Switchboard" --> "External Domain Routes"


The site requires an OpenAI Key and describes doing this as "risky but cool" ... What data would be exposed by sharing my key?


Hey, this is Steve from tldraw, I was up late last night putting this together.

I've added a note next to the input with more info here, but basically: the vision API is so new that its immediately rate limited on any site like this, and because OpenAI doesn't have a way of authorizing a site to use their own API keys (they should!), this was the best we could do. We don't store the API key or send it to our own servers, it just goes to OpenAI via a fetch request.

Putting an API key into a random text input is obviously a bad idea and I hope this doesn't normalize that. However, you can read the source code (https://github.com/tldraw/draw-a-ui) and come to your own conclusions—or else just run it locally instead.


It is possible to detect CSAM in end-to-end encrypted messaging by doing it on-device on the client side before it is encrypted and/or on the receiving client side after it is decrypted. iMessage already does this in the latest release. Most smart phones have AI-enabled chips that would be able to run images/videos against classification algorithms. The tricky part would be enforcing that users use clients which do this, so the task becomes regulating allowed messaging clients, which might be impossible. That being said, one could probably knock out 80% of the problem by legally forcing the hand of all the major platforms to do client-side scanning. At that point, only the truly dedicated would move their comms to another platform. Mobile users are very susceptible to nudges.


I think the problem is different. This is not about a technical possibility. This is about who will submit and manage the CSAM fingerprints. With the technology it will be trivial for oppressive governments to query which citizens have a copy of a particular image on their phone.

Consider a scenario:

- you use whatsapp, end-to-end encrypted by an USA company

- someone, perhaps a random stranger, sends you an image in which there is a criticism to a ruling party in Dabujistan

- your whatsapp has turned on the feature to save images on your phone

- you happen to transfer via Dabujistan

With CSAM tech, and fingerprints managed by the governments, you might be subject to jail.


> This is about who will submit and manage the CSAM fingerprints.

Not it's not. It's about "Why the fuck should I be under constant surveillance?"

Our computers are practically brain extensions at this point. I don't want anyone wiretapping my thoughts or coming close to it by wiretapping my private conversations with my family. Fuck off.


The unfortunate part about a centralized CSAM list is that now you need a committee to review every CSAM addition (not just the hashes but the source material to confirm it's CSAM and not political) and the committee has to have enough people to make sure the committee isn't all in kahoots


iMessage does not do this in any release, that plan was abandoned due to legitimate privacy concerns. The feature that is implemented is a parental control that can be enabled on the devices of minors, that blurs any detected nude images with a warning 'do you want to see this'.

It's not possible to detect CSAM without breaking the security model of the system for everyone, if the system can make any kind of report of detected content to an outside entity. If the system scans messages client side and then sends anything to do with the message to authorities, that is breaking the end to end encryption.

This is either done by 'AI', which means huge numbers of false positives that are actually legal, private and probably intimate get sent to authorities (hence breaking the end-to-end security model for that legal content), or by a secret, un-auditable collection of hashes - which are still fuzzy matched, so there would definitely be false positives (again, breaking the security model for legal content), but potentially also Governments could start to add other, legal material to the database, such as certain political material to detect dissidents. Since it's un-auditable, there is no way to know whether it's actually just illegal material in the database.

So whether it's AI or PhotoDNA or whatever, there's no way to do it that doesn't break the security model and cause more danger to innocent people, including destroying the privacy of children as well as adult, law-abiding citizens.


It is worth noting that due to endpoint key escrow on by default in the non-e2ee iCloud Backup, iMessage is already presently broken and not e2ee as Apple has endpoint keys available to them to decrypt almost all iMessages that transit the service (Messages in iCloud) in realtime.

Even if you enable iCloud backup E2EE, or disable iCloud entirely, iMessage is still not E2EE as your conversation partners are escrowing (to Apple) the keys from the other endpoint.


Why should my phone be acting like I'm a criminal? That's like searching the bags of everyone who exits the supermarket, or police doing door-to-door house searches "just in case". What's next? Verify every photo I take with my phone?


Or make everyone go through metal detectors and millimeter wave scanners at the airport, take their shoes off, treat any liquid over whatever the small limit is like it’s bomb-making material (but still let that person fly; checkmate, would-be bomber!)…it’s all security theater. Notice how they don’t release their testing rates on how many of the test weapons and threats make it through TSA security, because then it would be too easy to point to that and rightfully assert that they utterly fail at their mission while wasting untold lifetimes worth of human time and make travel that much more miserable. https://www.schneier.com/blog/archives/2015/06/reassessing_a... (2015) is a good read on that if you don’t already know.

My point is that when politicians do something “to save the children”, it’s rarely about actually helping anyone but themselves.


Yeah that's what this person wants, to scan every photo you take...ick.


If the app is processing data in a way you do not want before sending it, especially one that will no doubt be constantly argued to scan for more and more things they find objectionable, then it defeats whole point of end to end encryption, and you might as well just not do it at all.


What classification algorithm can detect CSAM, given that humans cannot reliably determine someone's age? [1] [2]

[1] https://www.eldia.com/nota/2010-4-23-actriz-porno-salva-a-fa... [ES]

[2] anyone who still gets ID'd for alcohol despite being well over 18, and often over 25 too


Yeah, no one who’s actually had to work with this on a technical level would seriously suggest our current GPT-4 level of AI for detection. It’s hash-based with some sugar on top.


Do you imagine that a significant proportion of CSAM is shared by users who are so casual about it that they would be "very susceptible to nudges"?


I’m not sure if it’s a happy or sad thing how unaware most people, even the technically-savvy crowd, are about the extent of human trafficking and slavery in 2023. Is it proof that civilization is working how so many don’t need to concern themselves with hunting and gathering, fighting wars, fighting crime, or fighting in general to survive, and are free to spend their time on recreation and the pursuit of happiness instead of survival?


I suspect that a large portion of CSAM is nude selfies that might be susceptible to "nudges" in the behavioral economics sense.


This may well be true according to the legal definition, though a system that matches against a fixed list of hashes, perceptual or otherwise, rather than working on magical AI, would not catch those. However, if this is all that the measure would be effective against then this is rather at odds with the proponents' narrative which makes this out to be about pictures produced and shared by adults with criminal intent.


To hell with your "nudges". It It's a cutesy way of saying "flex of State power", and everyone effing knows it.

No. It's not appropriate.


I think that it's only going to get faster, easier, and more accurate to generate sexualized pictures and videos of someone younger than 18.

Whether you or I consider that "real" CSAM, is moot. What matters is that more and more girls are going to be deepfaked into content they didn't consent to (and in fact can't consent to due to their age.

The proliferation of that content will lead to new laws driven by parents and politicians eager to "think of the children". However impractical, I could see image generators being treated like drugs or firearms and being highly restricted or banned.


Please don’t AI detect CSAM. That is a disaster waiting to happen.


It works great! Until it doesn't, and then someone gets put into jail and the court doesn't bother reviewing the AI's verdict because how could it go wrong?


It's not that you would end up in jail (although granted, that level of fuck-uppery is possible), it's just that anyone flagged would go through hell with real-world consequences before everything is cleared up.


Even if no one charges you it still creates a mess for the accused. We already saw how google handled a verified false positive scan that the police determined was innocuous.


And do not hash detect it either. If you mass scan eventually you are gonna hit a collision .


A greater point here is that end to end encryption in this context is almost entirely a lie.


How do you plan to do that without having a database of known CSAM on the device?


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