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Backblaze's 6 TB Hard Drive Face-Off

crow Re:360K already double-sided (146 comments)

Thanks for finding that source! I was looking at the list of floppy disk formats on Wikipedia to respond, and it didn't have that.

80 cylinder, 96 TPI

This was the second type of 5.25" drive made, and the least popular (and known) of the three types of drives. These double the capacity of the original drive by doubling the number of cylinders (tracks) from 40 to 80. They use the same media as the the 40 cylinder 48 TPI drives, but it is certified (tested) on all 80 tracks, as opposed to the standard disks which were only certified at 40 tracks.

These drives were never common on PCs, although DEC used a single sided version called the RX-50, in the DECMate word-processor, the DEC Rainbow and several other DEC computers, including the PDP-11 and the VAX.

Other than the DEC RX-50, these drives were almost always double sided, and recorded in double density MFM. They had a capacity of around 720K. Like the 40 track drives, they used 300oe media, and the drive rotates at 300 RPM

So apart from one very rare example, if you're talking 5.25" disk floppies, 360K meant double-sided. I expect the vast majority of people cutting out the notches to flip over their disks were using Apple II, Atari, or Commodore computers. In that realm, 90K was SS/SD and 180K was SS/DD. Most users didn't have double-sided drives until the IBM PC started using 360K DS/DD disks.

12 hours ago

Backblaze's 6 TB Hard Drive Face-Off

crow 360K already double-sided (146 comments)

Sorry, punching the tab out on the other side so that you could flip the disk over only worked on single-sided drives.

Single-sided, single-density: 90K
Single-sided, double-density: 180K
Double-sided, double-density: 360K

So if you were already at 360K, you were already double-sided.


Seagate Bulks Up With New 8 Terabyte 'Archive' Hard Drive

crow Just in time. (219 comments)

I am just about to build a FreeNAS or NAS4Free box. I was planning on running three 4TB drives to give me 8TB usable, but I'm probably better off with a pair of these. I'm mostly using the storage for TV recording, so the slower speed is fine. If the slower speed also means lower power, then it's a big plus.

4 days ago

Time To Remove 'Philosophical' Exemption From Vaccine Requirements?

crow In Massachusetts... (1037 comments)

Mass. Gen Laws ch.76, Â 15:
"In the absence of an emergency or epidemic of disease declared by the department of public health, no child whose parent or guardian states in writing that vaccination or immunization conflicts with his sincere religious beliefs shall be required to present said physicianâ(TM)s certificate in order to be admitted to school."

So there's broad religious exemptions such that anyone willing to claim them can skip the process, but if there is a serious outbreak, then suddenly the exemption goes away. That's not a bad compromise.

I haven't heard of the state ever declaring such an emergency, but I hope they are ready to do so before an outbreak becomes a full epidemic.

5 days ago

FreeNAS 9.3 Released

crow Compare with Nas4Free? (115 comments)

I'm planning on setting up one of these in a month, and I'm considering FreeNAS and NAS4Free. I'm very interested in comments from anyone with experience with both.

about a week ago

Dad Makes His Kid Play Through All Video Game History In Chronological Order

crow Nitpick on the linked article (222 comments)

At the top of the article, it shows an Atari 2600 in front of a TV. Displayed on the TV is Pac Man. But it isn't the 2600 version. It looks like the 800 version, or possibly the 5600 version (which was only slightly different).

Mixing up the graphics like that is just wrong.

Especially when the 2600 version of Pac Man was notorious for being so horribly bad. If only it had looked like that.

about a week ago

Just-Announced X.Org Security Flaws Affect Code Dating Back To 1987

crow Re:from TFA (170 comments)

Doesn't prohibiting network connections to the X server rather defeat one of the major features of X?

Granted, I think I usually am tunneling my X connections through ssh, so perhaps this doesn't apply as widely as it did a few years ago.

about a week ago

Overly Familiar Sci-Fi

crow Nonsense (367 comments)

Look how similar our culture is to that of the Roman Empire. Yes, technology has changed every aspect of how things are done, but the culture itself isn't much different. The Roman historian Suetonius was writing thousands of years ago about how they were upset about the decay of family values.

about two weeks ago

You're Doing It All Wrong: Solar Panels Should Face West, Not South

crow Re:obviously they should track the sun (327 comments)

Tracking the sun is out of the question when it comes to rooftop solar on sloped roofs. You're pretty much stuck with having the solar panels match the slope of the roof.

For ground-based installations or for large flat roofs, you would think it makes sense, but it would seem not, as I see solar farms all over the place (in Massachusetts), and they're all fixed installations. If it made economic sense to track the sun, then I'm sure the large farms would be doing it. Even with the production credits (SRECs they call them here), where you can get upwards of $.50/KWh, they're still not tracking the sun.

Can someone who has actually looked at the costs of sun tracking comment? I keep seeing assertions like the poster above, but I've never heard real numbers.

about two weeks ago

Jackie Chan Discs Help Boost Solar Panel Efficiency

crow Re: Mass produce! (194 comments)

Actually, using electricity to produce fuel is something that can have practical use:


In short, it's relatively easy to deploy a small nuclear reactor (much like one found in a submarine) to an operational base. If the excess power can be used to synthesize fuel, then that fuel doesn't have to be trucked in, which is a massive savings in a combat zone.

Also, it's a potential way of storing excess production, such as when demand drops overnight.

about three weeks ago

Jackie Chan Discs Help Boost Solar Panel Efficiency

crow Electricity vs. oil (194 comments)

Electricity and oil are both energy. You can substitute one for the other, though obviously there's advantages for certain forms in certain uses.

For home heating, oil, natural gas, and electricity are all viable depending on the cost. Right now gas is the cheapest and electricity is, in most places, the most expensive. It would take a lot of progress to get electricity to be the most economic solution for heating.

For aircraft, the weight of batteries rules them out.

For cars, Tesla is proving that electricity is an option. I know that we just signed a contract for solar panels on our house to produce more than we currently use on the assumption that we'll need the extra production to power our next car.

about three weeks ago

Why CurrentC Will Beat Out Apple Pay

crow SQUIRREL! (631 comments)

Not to dispute your point, but your conclusion is wrong. When the largest backer is Wal Mart, you don't assume a high I.Q. in the customer base.

about a month and a half ago

Building All the Major Open-Source Web Browsers

crow Re:Easy with Gentoo (106 comments)

I agree that it should be easy. My point wasn't to rely on distributors for building. It was that the work has already been done for major projects like the ones listed, so you can get a sense of their build complexity by looking at what they had to do.

For example, here are some ebuild sizes:
gcc-4.9.1 1556 bytes
mythtv-0.27.4 9796 bytes
firefox-33.0 11698 bytes
libreoffice- 18473 bytes
chromium-40.0.2194.2 18610 bytes
netbeans-ide-8.0 29367 bytes

That's a rough approximation of complexity. Sure, you can have a long but simple ebuild with comments and trivial stuff. You can hide lots of complexity in an eclass file. But it's a starting point.

As you can see, a project that uses a typical autoconf setup like gcc, while a very large project, has a very simple ebuild script. Meanwhile, Chromium and LibreOffice are quite complex. I don't know much about netbeans, but it's the largest ebuild in Portage right now. Other large ebuilds include openldap, ghc, php, and ati-drivers.

about 2 months ago

Building All the Major Open-Source Web Browsers

crow Easy with Gentoo (106 comments)

Of course, if you use a source-based distribution, it's easy, but that's not the point. If you download the source and build it yourself, you'll have to learn a bit about how they manage the build environment. You'll have to handle being sure all the dependencies are installed. You'll have to figure out any configuration options.

That's exactly what people who make distributions do. If you want to see how complicated the build is for any piece of software, just look at how complicated the build scripts are for various distributions. I expect you can find these for the binary distributions. With Gentoo, just look at the ebuild file.

about 2 months ago

Ebola Vaccine Trials Forcing Tough Choices

crow Harder if mildly effective (178 comments)

The difficulty in determining the effectiveness of the vaccine when you give it to everyone is dependant on how effective it is. If it reduces the chances of exposure resulting in infection by 10%, then yes, it will be tough to show that it's not useless. However, if it reduces the chances by 90%, it will be quite obvious.

about 2 months ago

Test-Driving a $35 Firefox OS Smartphone

crow Not legal in the USA (132 comments)

It doesn't have a GPS. Doesn't that mean it's not legal in the USA? I thought that was required for all phones so that if you call 911, the dispatcher will know where you are. I also thought that the GPS was integrated into the chipsets that they have to use for other basic features anyway.

about 2 months ago

Google's Security Guards Are Now Officially Google Employees

crow Good and Bad (134 comments)

There are good things and bad things about hiring workers directly for things like security. At the tech company I work for, we hire outside services for security, landscaping, stocking the coffee stations, and running the cafeteria. Obviously these workers aren't getting the same benefits package that direct employees get. On the other hand, it lets the company focus on doing what the company does and letting other companies specialize in other services.

It's rather like using an outside cloud vendor for IT services instead of implementing them in-house. The only difference is that the people doing the work are doing it on-site.

It also means that the outside contractors are treated differently when there are layoffs. The company decides to reduce headcount, but the service contracts are managed under different budgets, so those workers aren't cut.

about 2 months ago

A Garbage Truck That Would Make Elon Musk Proud

crow Re:Low hanging fruit (174 comments)

FIRE TRUCKS: They rarely have to travel more than a few miles at a time, with plenty of time to recharge. And they're all ridiculously expensive already, so the added cost of batteries is insignificant.

about 2 months ago

Google To Require As Many As 20 of Its Apps Preinstalled On Android Devices

crow Why all the separate PLAY apps? (427 comments)

I use the PLAY store to get apps, and it has a bunch of other stuff integrated like music and movies that I ignore. That's fine. Buy why are there now all these separate PLAY apps? What's the point?

about 3 months ago



Two Lost Doctor Who Episodes Found

crow crow writes  |  about 3 years ago

crow (16139) writes "Two episodes of Doctor Who from the 1960s, thought to have been destroyed in the 1970s, have been found. Both were in the hands of a private collector who didn't know what he had. Like most episodes of the time, these were half-hour shows, part of a four-part story, and portions of both stories are still missing."
Link to Original Source



Drinking age, status crimes

crow crow writes  |  more than 12 years ago A friend asked, The drinking ago: pro or con?

I'm of mixed opinion. I'm uneasy about the idea of status crimes. From a pragmatic perspective, I believe (though I haven't researched the statistics) that raising the age from 19 (as it was in many states) to 21 did, indeed, succeed in reducing drunk driving fatalities.

I think the problem is that our culture is not one in which we are taught to drink responsibly. Hence, when first given access to alcohol, the consumption is anything but responsible. By prohibiting such access until people are of an age where they are supposedly more responsible to begin with, such irresponsibility is minimized.

Not the best approach, but I don't see our culture changing teach more responsible behaviour anytime soon. On the contrary, I think we are still moving towards blaming others for our problems.

Of course, as one who doesn't drink, I may not have the best perspective on the topic.

Now on the related topic of the smoking age, I'm all in favor of the movement in California to raise the age to 21. Here my reasoning is very different: I don't think anyone should smoke, and setting a higher age should reduce the number of people who start smoking. This would be a move consistent with the trend to reduce smoking as a part of our culture. (California, like most western states, is large enough that the problem of people crossing the border to buy cigarettes is only an issue in a small portion of the state.)


Gas Tax at 40%

crow crow writes  |  more than 12 years ago

Today's thoughts on taxation:

The state tax on gas is $.21/gallon in Massachusetts. The federal tax is $.184/gallon. That's $.394/gallon, putting the pre-tax price at the pump under a dollar a gallon at the cheaper stations.

That's currently about a 40% tax.

Are any other forms of energy taxed at anything close to 40%?

Now granted, the government spends a lot of money keeping the transportation system going, but is 40% appropriate? How much does Massachusetts spend on transportation (excluding the Big Dig), compared with how much it brings in from the gas tax? What about the federal government?

Are gas taxes subsidising other government programs, or are other taxes subsidizing transportation? There are good arguements to be made for which way (if either) it should be, but I just don't have the information.

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