People have been speculating about how someone can turn a profit with power rates in NYC. It’s highly likely that this guy rents an apartment that comes with power, or he rigged a connection to an outlet in the common area.
I had friends who used to run hydroponics rigs in their apartments (for veggies!), it made sense because their landlord footed the bill.
The only electricity cheaper than hydro, is electricity where someone else pays the bill.
How much of the power used by something like this ends up as heat? The FCC notice says it was an "Antminer s5". A bit of Googling suggests it uses a little under 600 watts.
If most of that ends up as heat in his apartment, that could reduce his need for other heating which could offset some of the electricity cost, especially if that other heating is electric heating.
I wonder if it wasn't the miner at all. Maybe the guy had an (illegal) cellphone jammer as well, and somehow managed to convince the feds that it was his antminer causing the trouble.
"On November 30, 2017, in response to the complaint
agents from the Enforcement Bureau’s New York Office confirmed by direction finding
techniques that radio emissions in the 700 MHz band were emanating from your residence in
Brooklyn, New York. When the interfering device was turned off the interference ceased. You
identified the device as an Antminer s5 Bitcoin Miner. The device was generating spurious
emissions on frequencies assigned to T-Mobile’s broadband network and causing harmful
interference."
> You identified the device as an Antminer s5 Bitcoin Miner
They only narrowed it down to his residence, then he himself said it's the miner. It's totally possible he used it as a scapegoat for something else he was running.
It says the person shut it off and claimed it was an Antminer s5, not that the FCC verified what was causing the interference. Was there some additional 3rd party confirmation of what it actually was?
As a ham radio operator, this sort of thing is extremely common. Most cheap Chinese power supplies tend to broadcast a lot of noise.
Nowadays, it's mostly impossible to operate the short wave bands in a city due to all the static on the air. The regulation agencies have pretty much given up, save for the most egregious cases, due to how prolific the problem is.
One might imagine with better technology, something like noise-detecting spread-sprectrum or automatic link establishment, along with advanced DSP filtering would be able to dodge these sorts of noise generators.
The notice[1] says it was operating in the 700 MHz band. The wavelength for this band is 42.9cm. A few sources I found (StackExchange, Anandtech) say a Faraday cage is effective with a mesh 1/20th the wavelength.
Surrounding the device with metal containing 2.1cm (0.85in) holes would probably work and only require minor modifications to support heat dissipation.
Side note, now everyone knows Victor Rosario in Brooklyn probably has a bunch of cryptocurrency...
> Victor Rosario in Brooklyn probably has a bunch of cryptocurrency...
At 1155 GH/s, he has probably mined upwards of several dozen dollars worth of cryptocurrency this month. And an extra hundred dollars on his power bill, assuming it’s not included in his rent.
Brooklyn apartments this time of year are often poorly heated. If you're paying for the electricity to run a space heater, it might as well produce bitcoins.
And heat pumps are more expensive to buy and impossible for a tenant to install themselves in an apartment they rent from, which is why people use small portable and cheap resistive heaters.
And in that case, a miner is just as efficent if not more efficient since it's making the user some money (maybe).
Portable heat pump + air con. I've had something like this before, typically comes with something to slot/seal up into a gap from leaving the window open. Can be moved between rentals.
Efficient in what units? Heat pumps are more efficient in BTUs/kWh, but I doubt you've done the pricing to say they're more efficient in BTUs/dollar, because that's fairly complicated.
Sure, lets say $500 for a heat pump, $50 for a heater. Then what 'yield' are you getting on the $450. Let's say heat pump is 2x as efficient (should be understimate). Let's say that you run 2kw normal heater for 1 hr / day winter only for 3 months. That's 180kwh. @12c that's $21.6. So you save $10 a year. A 2.2% yield tax fee. So admittedly not great.
OTOH a mining rig, well who knows that IS complicated. You might lose money, or spend a lot of time tweaking but break even.
Strangely, the Antminer comes in a metal case with holes smaller than that. Maybe it wasn't grounded or something? Or it was radiated through the external power supply wires?
EDIT: mixed them up, Spoondoolies ones had a nice mesh but the Antminer ones don't behind the fans. That 1" of plastic must be enough to let a significant amount through (or the power supply wires still)
Yes they do. A Faraday cage is equally good at blocking radio waves going out as coming in. They don't protect against conducted emissions though - along a power cable for example - so they're not a complete solution.
Perhaps the radiation wasn't mostly coming from the Antminer box itself - each 700Mhz clock the rig draws current, the transformer propagates it back to the wall, and the power lines in the flat become a big antenna.
Powerline Ethernet has this problem, but it uses only a 25MHz carrier wave, so it only bothers hams.
While people are pointing out your mistake, it's worth bringing up the fact you were certainly thinking of: when it comes to static electric fields, a Faraday cage complete protects the interior from external charges but does nothing to shield the interior from the external charges. However, we are considering non-static electric fields and in particular ones at high frequencies.
However, I think the fact that the Faraday cage is not symmetric when it comes to static electric fields is very interesting. Ask yourself this: how does the cage know what "inside" versus "outside" means? You know the old joke where a mathematician has to enclose the greatest area with a given fence and so she takes the fence and wraps it around herself and declares "I am outside the fence." Well, why can't I declare myself to be inside the Faraday cage and suddenly get the benefits of its shielding?
You might say that the difference is that the outside has the "boundary" of the universe and that makes it distinct from the inside. [1] But we don't yet know that the universe isn't finite and wrapped up on itself spatially, so if that were the difference, then isn't a Faraday cage experimental evidence in favor of the universe not being finite? I think therein lies the answer: if we wanted to actually use this as an experiment, we would have to place a charge outside of the Faraday cage and wait for sufficiently long time that the electric field is effectively static. However, for our experiment to work, we would have to wait so long that the electric field becomes static on the scale of the entire universe. And so no, the Faraday cage is not an experiment we can practically perform to measure the shape of the universe and the difference is the obvious one: the exterior is the larger one and is simply just "big enough" that we can't ever wait for the EM fields to settle down in the exterior like we can on the interior.
[1] Mathematically, this come in as the fact that the Poincare lemma https://en.wikipedia.org/wiki/Closed_and_exact_differential_... requires a "contractible" domain. The exterior of the cage is not contractible, so we are not guaranteed to be able to use the integral forms of Maxwell's equations over the exterior of the cage. However, the interior is contractible.
>So for all intents and purposes, the cage generates the same DC electric field that it would generate if it were simply affected by the charge placed inside.
I think what he means when he asked what you are on about is what is the difference between "protects" and "shields"?
You said:
> Faraday cage complete protects the interior from external charges but does nothing to shield the interior from the external charges
So you are saying that the interior IS protected from but IS NOT shielded from the exterior charges. Most people would expect "protected from" and "shielded from" to mean the same thing. Hence the confusion.
“Faraday cages are also used to enclose devices that produce RFI, such as radio transmitters, to prevent their radio waves from interfering with other nearby equipment.”
Sure they do, that's how microwaves avoid heating people standing nearby. However, getting the power in without letting the RFI escape the power connections is the tricky bit.
So explain how you can stand next to your microwave then? Did you think the size of the holes in the metal mesh of the window was consistent across all microwaves by coincidence?
I presume this was only messin' with the folks next door or something? Could a device like this impact t-mobile in a meaningful way? If it was just one or two customers, t-mobile managed to get the FCC to actually go find this thing??
I've heard they take ANY interference very seriously. That's why HAM radio operators are licensed, and if you operate outside of your allowed bands, yes they'll probably show up.
Somehow it doesn't surprise me that Bitcoin mining hardware is generating harmful RF interference.
If I was a miner, I'd be quite worried that someone with direction finding equipment could easily discover a hidden mining location. The FCC or another government entity finding you is kind of the best case scenario if you think about it... :)
A single S5 caused the interference? Something doesn’t add up with this story.
A fleet of Antminers, perhaps, but even that would be unlikely.
Edit (addendum):
Details about the stock unit’s noise output; Antminer S5 runs at 61 to 65 dB at 4 feet. Modified S5 with a higher-quality fan dropped the measured sound intensity to 48 dB[0].
Follow-up Edit:
I just noticed that I’d clipped a section of my response...which would have made it clear that my doubt was that the S5 put out emissions that interfered with T-Mobile. I referenced sound later, but only intended that to be a point of reference.
I had friends who used to run hydroponics rigs in their apartments (for veggies!), it made sense because their landlord footed the bill.
The only electricity cheaper than hydro, is electricity where someone else pays the bill.