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Comment: Re:Lead Acid (Score 5, Interesting) 309

by aXis100 (#49608683) Attached to: Tesla's Household Battery: Costs, Prices, and Tradeoffs

Im not convinced. It's good that you've rated that pack at 50% depth of discharge (48V x 400Ah = 19kWh nominal, approx 10kWh @ 50% DoD), but typically lead acid packs will only get 1000 cycles at that rate. You typically have to go to a 30% DoD to get 10 years / 3000 cycles.

Lithium can do greater depth of discharge for far more cycles. The overall lifetime costs of lithium per kWh were already starting to beat lead acid, and the new Tesla pack is even better.

Comment: Re:Thinking . . . High Speed Trading Code (Score 1) 84

Stuff minutes. Make it hours or even a whole day. Anything less is speculation.

The stock market should be promoting real investment - i.e you do some research and have an educated opinion that a company will do well. You buy shares, wait for the returns and then sell when things have stabilised. That process takes time - months or years even.

Comment: Re:The 3d printed elephant in the room (Score 1) 52

by aXis100 (#49332433) Attached to: Australian Company Creates Even Faster 3D Printer

The commonly used ABS plastic used in FDM machines is very durable, but the orientation of the print matters. You do have to design the prints so that the weak join between layers doesnt experience stress.

I do agree with the looking horrible part, but you can do funky things like acetone dips or acetone vapor to smooth and gloss them.

Comment: Re:They indeed look very much like incandescents (Score 1) 328

by aXis100 (#49246399) Attached to: New Crop of LED Filament Bulbs Look Almost Exactly Like Incandescents

That's got nothing to do with the LED and everything to do with the driver electronics. Unfortunately the packaging they are in limits the size of the driver circuitry significantly so i guess it's going to be more common with these filament bulbs.

Comment: Re:B.S. Alert (Score 1) 88

That's a bit harsh and fails to see the significance.

From the article: "There are no analog circuits, no filters, no chokes, none of the traditional circuitry and components expected in a radio transmitter."

If it can be built as an peripheral chip, it can also be built onto the same silicon as a microprocessor.

Comment: Network file transfer (Score 1) 466

by aXis100 (#49143381) Attached to: Ask Slashdot: Old PC File Transfer Problem

Windows 3.11 machines were capable of SMB file sharing over a network. You should be able to use an old PCMCIA ethernet card and install the Microsoft TCP stack (it wasn't installed by default), then see other computers over a workgroup.

If that sounds too hard then serial transfer over null modem should be the easiest and I'm sure I did it many times myself back in the day. I cant remember what software I used to use, googling for Windows 3.11 serial file transfer shows lots of hits though.

Comment: Negative feedback loop (Score 1) 389

by aXis100 (#49077193) Attached to: What To Do After Robots Take Your Job

So, robots start replacing jobs because they can make widget X cheaper.

As unemployment increases, less poeple will have the money required to buy widet X. The manufacturers will have to lower prices in order to get sales, and their cost reductions through robots will evaporate. Meanwhile everything just got cheaper.

At some point we'll reach equilibrium again, where the cost benefit of adding a robot will be balanced by the lack of sales due to poeple not having an income. It might be painfull for a while until we get there, but it will happen.

Comment: Re:Equally tiny UPS? (Score 1) 180

by aXis100 (#48815719) Attached to: Tiny Fanless Mini-PC Runs Linux Or Windows On Quad-core AMD SoC

These low power PC's are opening up new opportunities for UPS's, namely that they all run off low voltage DC (nominally 12V) and open up the possability of a 12V UPS. It saves on the inverter required in the UPS, and increases the overall efficiency.

For a device like this with a variable input voltage you can run it directly from a 12V SLA battery, and then keep the battery topped up with a decent mains charger rated to higher power than the PC. You can generally do the same thing with access points and 12V network switches, and any 5V devices can be run from a $5 step down DC-DC converter.

The only problem I've had with this method is 3.5inch USB Hard Drives, as they usually require a well regulated 12V supply. For those I bought a fancier buck-boost DC-DC converter, they were a little pricier and harder for find than, but still quite reasonable.

In the end you may have 30W worth of devices hanging from the SLA batteries, then just buy a multistage charger rated to the next higher power - eg 30W = approx 2.5A @ 12V, so get a 3 or 4amp charger. You can expand to as many parallel as you like, all it does is slow down the recharge time.

Comment: Re:Ocean Seeding (Score 1) 319

by aXis100 (#48770569) Attached to: How Close Are We To Engineering the Climate?

I've seen studies on that before.

One of the best ways to seed the oceans is with the addition of iron based minerals. Plants in the food chain need this to grow, but it's very scarce in the ocean. Historically there was a natural seeding process as iron laden dust was blown off the coastlines, but human development has reduced that source.

Comment: Re:Conform or be expelled (Score 1) 320

by aXis100 (#48762237) Attached to: HOA Orders TARDIS Removed From In Front of Parrish Home

In Australia we get a Strata Title deed, with common shared assets managed by a strata management company.

For simple blocks subdivided into a few houses, the homeowners can form their own strata company with little to no costs. For apartments buildings they generally employ a third part to manage it, and residents will then pay monthly strata management fees.

The more I want to get something done, the less I call it work. -- Richard Bach, "Illusions"

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