Category: Internet

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Help Astronomers Online at Galaxy Zoo

Galaxy Zoo is a site that has over a quarter million galaxies collected through the Sloan Digital Sky Survey (SDSS) from the robotic telescope at Apache Point Observatory, New Mexico. The astronomers need people’s help classifying the galaxies. It turns out that people are much better at this than computers.

You sign up on the site and are asked to classify a galaxy as simply smooth and rounded or having signs of a disk. You then classify how rounded it looks. There are other questions that you might be asked, listed on the How To Take Part page.

Don’t worry if you are unsure. Sometimes it is a judgment call. Galaxy Zoo presents the same image to lots of people and takes a vote on the best answer.

So far, they’ve learned that more spiral galaxies and blue elliptical galaxies exist than previously thought. There are an equal number of clockwise and anti-clockwise spirals. And there are some unusual objects (blue image below galaxy to the right) that have been noted for astronomers to investigate further.

It’s easy to classify stars on the site and you will be among the first people to look at these galaxies in detail.

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7 Misconceptions about Over-the-Air Digital TV

As I help people with home theaters and TVs across the Washington D.C. area, I run into many misconceptions about over-the-air digital TV.

1. Digital TV? What is that?

Most people still don’t seem to realize that they can receive high definition television over the air.

Not only is it high definition, but over-the-air (OTA) broadcasts also generally provide better quality video than cable or satellite. This is because the bitrate (amount of data transmitted) of OTA broadcasts is typically higher.

While not all the channels are available (no CNN, Comedy Central, Discovery, Home & Garden, etc), you do get in Washington D.C. and generally: ABC, NBC, CBS, PBS, Fox, CW (formerly WB), Univision (Spanish language), and an independent channel or two.

2. The digital transition, whenever it occurs, will be a switch from analog to digital.

Not exactly. The digital channels are all available now. The “digital transition” date is actually just switching off the analog channels. The analog spectrum was sold a year ago by the US government sold to a consortium of bidders including AT&T and Verizon.

3. The analog shut-off date is when?

It was originally today, February 17, 2009. But Congress and Obama passed legislation to delay it until June 12, 2009, because many people are still unprepared for the transition and the government ran out of coupons for people to buy converter boxes.

The complicated bit is that because of costs associated with running the analog systems, hundreds of local stations will still try to shut down their analog signals today, if they can get the FCC to go along with that. In Washington D.C., all stations will continue to offer analog channels until June 12th.

According to the Associated Press:

A patchwork of 641 stations across the country, mainly in thinly populated areas, are still turning off their analog broadcasts this week or have already done so. The most populous markets where many or all major-network stations are cutting analog include San Diego and Santa Barbara, Calif.; Providence, R.I.; La Crosse and Madison, Wis.; Rockford, Ill.; Sioux City, Iowa; Waco, Texas; Macon, Ga.; Scranton, Pa.; and Burlington, Vt.

4. I need a coupon and converter box.

TVs sold over the past few years typically have a built-in digital tuner. Also, the $40 coupon is only good for the converter boxes that output their signal in analog.

This means that if you have a shiny new HDTV, you are probably fine because it has a tuner already. And if you have a slightly older HDTV that does not have a tuner, you will be better served with a converter box that has an HDMI or component video out so that you get a digital signal to the TV itself instead of analog. And those better converter boxes do not qualify for the $40 coupon.

5. I just need to plug my antenna into a converter box to get a signal.

You will need an antenna and just plugging in your existing one might work. But the antenna is probably best not placed where you used to have it.

Digital signals tend to be more sensitive to placement and interference from walls and obstructions. Therefore you want the antenna to be as close to possible to line-of-site to the tower as you can get it. This means placing the antenna in a window, on a roof, or high up in your attic. People who live close to the transmitting towers (within 5 miles) should not have problems. People farther away will need to spend more time and money to get the right equipment.

6. My “rabbit ear” antenna will work fine.

It might if you live within a couple of miles of the antenna. But most people will be better served with a new antenna and spending some time placing it correctly in the best location.

My favorite resource for determining antenna needs is antennaweb.org, which has a Choose an antenna area. This will allow you to see how far your towers are from you and the direction of the towers. Direction is important because most HDTV antennas are directional.

For my installations, I generally start with antennaweb.org’s data and then paste it into a spreadsheet like this. Then I can write down the signal strength for each channel using different antennas and locations. It usually takes a while to get the optimum setup.

Also note that in the D.C. area, most digital channels are on the UHF spectrum, but after the analog shut-off both ABC and CBS will be changing to transmit over VHF. The implication for customers is that several antennas only work well for UHF or VHF. Keep that in mind when looking for an antenna. Many stations across the US plan on changing their transmissions after they shut down their analog stations. Antennaweb.org lists these planned changes.

AVS Forum has a vibrant discussion of what antennas are best. I agree with their list and have had great luck both with the Winegard SS-3000 and Terk HDTVa. Both of these have amplification which you may or may not want to use depending on how it affects your signal.

7. I can’t watch over-the-air television. I’d miss my TiVo or Cable DVR too much.

The TiVo Series 3 and TiVo HD do actually tune and record OTA broadcasts. Not only that, but they can record both OTA and cable signals at the same time. So you could get basic cable for a few channels that you are missing, and get pristine high definition content over the air. TiVo does have a monthly service fee (also available as a lifetime purchase for the life of the box).

For those who want to get rid of all monthly bills and just have an OTA DVR, the satellite folks at Dish network came out with the DTVPal DVR currently for $249. You don’t use the Dish network at all. They simply took the software in their good (not as good as TiVo) DVR and repurposed it. There is a discussion of the DTVPal DVR at AVS Forum, which they jokingly refer to as the reboot/upgrade club because of the problems that the early adopters are facing. Currently the DTVPal DVR is out of stock. I would expect Dish to iron out the issues and make this a solid box, as their satellite DVR is pretty good.

Cut the Cable or Satellite Bill

While the hurdles may seem daunting, the ability to get great content in high definition over the air is great. With some time and research, you might even be able to ditch your cable or satellite.

Internet TV

Another option that complements OTA programs is Internet based TV. Projects like Boxee are promising. They connect to CNN, Comedy Central, and tonnes of other streaming media. While the quality is not HD, this provides another way to cut the cable or satellite bill.

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Kindle 2 Announced

The long awaited Kindle 2 by Amazon was finally announced today.  It was just as the rumors predicted in appearance.  It has several desired improvements but a few shortcomings as well.

Shape and Size

The Kindle 2 is more attractive than the original.  The new thinner design is impressive.  The tradeoff is that the device now has a bigger footprint.  In some cases the original Kindle would fit in your purse, the Kindle 2 may not.  But the same is true for the thickness giving the Kindle 2 an advantage.  With its new thinness, the Kindle 2 can probably fit more easily into some thin pockets in a bag.  Overall, the new shape is an improvement.

Battery Life

The Kindle 2 has 25% more battery life than its predecessor.  The original Kindle had a very impressive battery life already. It is a good idea to turn off your wifi when you aren’t downloading a new book to get longer battery life.  Under typical use of a heavy reader, the original Kindle would last a good week with wifi off.  More battery life is always a welcome improvement to any gadget though.

Page Turning

The page turning buttons have been redesigned.  One of the biggest complaints about the original was how easy it was to unintentionally turn a page.  The Kindle 2 buttons are smaller so they are not as easy to hit accidentally.  Another welcome improvement is pages now turn 20% faster.  The first Kindle wasn’t exactly slow at page turning but you were often left wishing the page would render just a little faster and now the Kindle 2 does.

Storage

Amazon claims “more storage” in the Kindle 2.  This is a bit inaccurate since it really just has more built-in storage.  The original Kindle had an SD card slot for extra storage which means it could hold more if you used that slot.  The Kindle 2 does have more built-in storage but has removed the SD card slot so you are stuck with just the internal memory.  That isn’t a big problem since the internal storage can hold 1,500 books now.  And if you fill it up, you can delete books but still own them.  At any point, you can have a book re-downloaded to your Kindle.  The SD card slot was probably removed to help allow the device to be thinner.  While this is technically a lost feature, it is an acceptable tradeoff for the new thinness.

Screen

The new screen is very similar to the original except that it now has 16 shades of gray.  This allows pictures to look much better.  If you just read books, this is almost pointless.  But if you read newspapers on your Kindle, this will greatly improve your reading experience.

Book Cover

The original Kindle included a leather book cover.  Unfortunately, now this is a $29.99 accessory for the Kindle 2.  To protect your expensive Kindle 2, you have to buy the book cover which makes the Kindle 2 more expensive than its predecessor.

Conclusion

Most of the changes are positive.  Overall the new Kindle isn’t a huge jump over the original, it is more of several small design improvements.  This is a device any avid reader should definitely have.  For a full description of it, check out the Amazon Kindle 2 page.

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Wireless Draft N Compatability Issues

There are many flavors of wireless networking. Most common are 802.11B, 802.11G, and now 802.11N (Draft). 802.11N is “draft” because the standard has not yet been formalized, despite the sale of draft-N devices for over a year. For most people, this won’t cause a problem. But hitches do come up.

Draft N Works, Usually

When I was recently setting up a D-Link draft-N router with a MacBook Pro, I noticed that the wireless connection would drop regularly or show a connection but be unable to receive/transmit. This was due to the incompatable N implementations. The solution is to go into the router settings and switch it to only using B/G. In most cases, I have found draft N devices to work without any issues.

Future of WiFi Standards

The 802.11N standard is expected to be finalized by the IEEE LAN/MAN Standards Committee (IEEE 802) in November 2009. Then all the current draft-N manufacturers promise a firmware upgrade that will make them interoperable. Of course by November 2009, we might be looking at buying new draft wireless standards, as described by PC Magazine:

802.11s, a mesh networking specification that’s been on the drawing board since September 2003. (It probably won’t be final until September 2010.) Laptops and other devices with 11s support will function as mesh points (or MPs) and form links with each other, allowing packets of data to skip from device to device across the network as needed. Mesh has been around for a while in many proprietary forms, and is important not only because it can extend a network’s range but also because it has self-configuring abilities: Mesh devices can move about without impacting overall performance. In such a network, data will hop around from mesh point to mesh point along the shortest path to where it needs to go. Actual 11s is already in use in at least one product: the One Laptop per Child project’s XO laptop uses it to communicate with XS school servers, in some tests over distances as great as 2km with 802.11s data hops from device to device.

802.11u, called “InterWorking with External Networks,” will provide a Wi-Fi device with methods of connecting securely to a network, based on the external network’s type. For example, if you have access to the cellular connection that provides Internet access to the Wi-Fi router on a bus, 11u will keep that connection secure. It will also allow a Wi-Fi device to discover more information about that external network, such as whether it’s free of charge or not. 11u could be published by March of 2010.

802.11z “Direct Link Setup” is the 802.11 Working Group’s take on improving ad hoc connections, at least for business users. It’s entirely unrelated to what the Wi-Fi Alliance is doing for device-to-device communication. 11n allows two laptops that would normally communicate on a secure network to form a P2P connection to talk to one another exclusively. This happens only after they’ve authenticated security credentials through an AP. It’s a super-secure ad hoc that requires the right security setup.

See a full list of 802.11 standards and approval timelines from IEEE.

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Down & Up Worm Worst Ever

Over the last few months, the “Down and Up” worm, also known as “Conficker” has infected an estimated 6% of all PCs worldwide. The concern is what the authors will now do with all these compromised systems. They could ask for credit card information as the bogus Antivirus 2009 does. They could use the computers to attack and demand money from websites through denial of service (DOS) attacks. No one knows yet what the intentions of the authors are.

It is considered the most professional and pernicious worm attack that researchers have yet seen. It effects all versions of Windows. As a worm, it does not require any user action for the computer to be compromised. The machine must just not be recently patched.

Download the Malicious Software Removal Tool (also available in Windows Updates) in order to protect your computer or to possibly get rid of the worm (most people who have it do not know). Then you can feel comfortable that your computer is owned by you and not by the bad guys.