Dan's Data letters #162
Publication date: 12 March 2006.Last modified 03-Dec-2011.
"Suspiciously cheap", defined:
I'm looking at buying an NTSC plasma TV on eBay.
[link to listing on ebay.com.au for a sixty inch LG MU-60PZ95V, which ended up going for a mere $AU3401.01. The Australian equivalent model lists for seventeen grand. Astoundingly, the seller is for some reason no longer a registered eBay user.]
The product description mentions that the screen works from 15.73 to 68Hz (H) and 50 to 120Hz (V).
I was wondering if this screen will work in combination with a HD STB in Australia?
Of course I need to buy a power converter.
The price seem ridiculously low, so maybe it's just a big scam.
Filip
Answer:
Seeing as that guy had never actually sold anything before, I advised Filip that this auction would not be
my first choice. And lo, Filip did not elect to bid, and is
glad that he did not.
Regarding genuine sales of foreign-model plasma screens and other home-theatre display devices, as opposed to made-up stuff, bear in mind that local support from the manufacturer is likely to be pretty limited, and the seller probably won't be able to help you out with problems, in the unlikely event that he wants to. So, practically speaking, there's little chance of any support, let alone actual warranty support, even if you can persuade the manufacturer that you're the original purchaser. They'd just tell you to take it up with their branch in the country where the screen was sold, and invite you to enjoy paying to ship your fragile 70-kilo screen to and from said country.
All that aside, though, all of the inputs except composite and Y/C don't come in PAL/NTSC versions, so anything with an RGBHV ("VGA") or other HD output should work fine with a screen like this, regardless of country.
Magic/More Magic
I have a little surround+sub speaker set from Altec Lansing for my PC, and mostly it's a capable, if not particularly beefy, setup. One day it dropped the right channel though, and when fiddling with wires didn't help, I assumed I had fried something and hung my head with sadness. I also moved houses.
In the new house, I didn't have a good spot for the surround speakers, but for some reason I wired up the surround port anyhow, and lo and behold I got my right channel back. Later, when I unhooked the surround cable (but not the regular feed) I again lost my right channel, but here's where it gets weird. So: primary audio out from PC going into primary audio in on the speakers (all the plugs are on the sub) gets me no right channel. As I'm plugging the surround cable in to the sub, with the other end of the wire still sitting on the carpet, not yet plugged into the computer - I get my right channel back. Unplug cable, lose it, plug it back in, it returns. All while the other end of the cable is sitting on the floor.
Tell me there is a sensible explanation for this beyond "plugging it in might have shifted a broken solder joint on your primary" because I assure you no amount of plug-wiggling will restore the right channel, only the magic wire to nowhere.
Suspiciously eyeing a disconnected audio cable,
Johnathan
P.S. Photo guru that you are, I would love to get your opinion on this, if you have the time and inclination.
Answer:
I'm guessing your speakers' subwoofer socket is switched. Many "headphone jack" sorts of sockets have a switching
function, commonly used to do things like disable speaker outputs when you plug headphones in. The switching function
can also, however, be used to disable an input when there's no cable plugged into it, to stop surround speakers
humming (and/or, for cheap computer sound systems, hissing) when they should just be turned off. Switched outlets
also let surround speaker sets "know" when they've only got a stereo input lead connected, and automatically send
sound to all of the connected satellites (including the centre speaker), and the subwoofer, despite not getting any
input for four of their six channels.
A sub channel switch should, of course, have no effect on the other speaker channels. But if something else is broken or shorted or whatever, I suppose it could happen. Result: The symptoms you report.
I'm not too sure about the "photo guru" thing. I have a medium level of knowledge about digital photography, and can take some reasonable product shots, and that's about it.
There's not necessarily very much of an overlap between technical photographic knowledge and practical competence at taking good pictures, anyway. The world abounds with amateur enthusiasts who're dedicated to spending the GNP of a medium-sized country on shiny new lenses, and/or fully equipped to debate the merits of the 1963 single-coated Wibblywoblikon primes for the East German medium format TLRs from the Clapp-Trapp factory, and are indeed so enthusiastic about such activities that they hardly ever find the time to photograph anything. And for every I-know-how-many-points-my-emulsion-particles-have legend like Ansel Adams, there are half a dozen prolific producers of excellent images who don't know an F stop from an organ stop, and are probably quite a lot happier as a result.
As regards your Megapixel Myth piece, though - yes, extra resolution is helpful when you're cropping. Pro photographers often crop non-studio shots quite heavily; happy snappers seldom do.
Sheer pixel number is often very much secondary to lens quality, though. You can buy tiny flat folded-lens cameras with five-megapixel and higher imagers in them now; the fact that the lenses in these things don't protrude from the body and take zero time to get ready to shoot is good, but those lenses can barely resolve 1600 by 1200 even when stopped down to a teeny aperture. So the extra pixels are a total waste of processing time, battery power and card space.
Conversely, ancient DSLRs with miserable pixel counts by current standards can, with a decent lens, take pictures that can stand a surprisingly high print size - though, of course, pixel count does put a hard upper limit on the image detail that can actually be captured.
(Yes, this does mean that if you're on a budget and see an old two-megapixel digicam that's got a good lens, hasn't had a hard life, and doesn't need some outlandish custom battery, for $50, you should buy it. Example: My old C-2500L.)
Your PowerShot S70 apparently has a quite good lens in it, which can (camera shake and shutter speed permitting) make quite good use of the 7MP sensor, so in its case the buy-extra-megapixels-so-you-can-crop argument holds water. It doesn't for a lot of consumer cameras, though, now that 5MP+ is the norm. For many current models, the top resolution setting is hardly worth using; it's only there so that the camera makers can keep up with the Joneses.
Unclean! Unclean!
I have a Toshiba 490XCDT Laptop running windows XP Professional. 266MHz Pentium II processor, 64Mb of RAM. I just use it to surf the Web and read e-mail.
I love everything about this laptop and am trying to keep it up to date. And I can't afford a new one.
Here's my problem. I plan on adding more memory, which I have found with no problems.
But I think I should also add a new hard drive. I am having trouble figuring which kind I should add. Do you have any suggestions?
The computer runs well but a bit slow. I sometimes get the icon in the lower right that says low disk space. Will adding a more memory and a bigger hard drive fix this?
Tracie
Answer:
Ee-yow!
A bit slow? A BIT SLOW?!
Your laptop is really, severely, unpleasantly below the realistic minimum WinXP specification. The CPU speed you can just about get away with, but 256Mb of RAM is the least I'd consider using, and 128Mb is Microsoft's rather unrealistic minimum specification. With 64Mb, you're flogging the hard drive non-stop every second you use the computer, as you've no doubt noticed. That's the swap file being used to make up for the lack of real memory, and swap is orders of magnitude slower than RAM.
The most memory you can put in a 490XCDT is 160Mb. If I had to use a computer with that little RAM, I'd stick with Windows 98, which runs much faster on older hardware. Or you could try one of the reasonably-like-Windows Linux flavours; if you can get someone to burn you a Knoppix CD then you can boot from that in your CD-ROM drive (I'm pretty sure your computer can boot from CD...) and see what you think without doing anything to your Windows install.
The 490XCDT uses a standard 2.5-inch ATA drive, but as normal with older computers, there's a maximum disk size it can recognise, which is rather smaller than the smallest drive you can easily buy new these days.
In the 490XCDT's case, the limit is 8Gb. If you swapped in a 20Gb drive, though, you could use 8Gb of it, which is better than nothing. Alternatively, you can use a "BIOS overlay" program, available from the hard drive manufacturer, which bypasses the system BIOS and allows it to recognise bigger drives, at the cost of making it even slower.
The smallest 2.5-inch drive a lot of places sell at the moment is 40Gb, though. The price of a 40Gb drive already exceeds the resale value of the laptop.
Personally, I'd take the money you're thinking of spending on RAM and HD upgrades and put it toward a second-hand laptop. Something with a processor not much faster than what you've got, 128Mb or more RAM and Windows 98 will perform a lot better than your current machine, and give you a whole spare computer!
(Tracie replied and explained that Hurricane Katrina ate her old, better laptop, and she got the Toshiba for free. Well... all right, then.)
If you decide to put Win98 on the 490XCDT, the easiest way (relatively speaking) would be to just nuke the drive and start fresh with 98.
Since you don't have much data on the old machine, because you can't have much data on the old machine, it's no big deal for you to back it all up (which you should be doing anyway, of course, if any of it matters to you) and start fresh. If you've got a network adapter then you can copy your data over the network to spare space on another computer; the 490XCDT also has a USB port that'd let you plug in a borrowed external drive or USB networking cable to back up that way. A single writable DVD will hold the entire contents of your drive; if you know any digital-photo enthusiasts, they'll probably have a USB memory card reader/writer and enough cards for you to back everything up, too.
The backup will take a while if you're stuck with 10BaseT Ethernet or the USB version 1 your laptop supports, but even at only half a megabyte per second (which is about as slow as it's ever going to be) you can copy a gigabyte every half hour or so. That's agonising if you're backing up 200Gb, but for 4Gb it's acceptable.
Once you've backed up, you (or the tame 16-year-old of your choice; note that the usually-recommended 14-year-old is probably too young to remember Win98) can install Win98SE just like in the old days. Boot from a 98SE boot floppy, use FDisk and Format to repartition and reformat the drive (it's probably in NTFS format at the moment, which Win98 and its boot floppies can't even read), and then install 98SE from CD. You can get clever and put your Windows files on hard disk as I describe in this old piece if you like, but it's not essential.
(This is also the stuff you'll have to do if you find an 8Gb drive for $5 or something, and decide to upgrade to that.)
Aaaand... quackery.
I would like to ask you to visit a site I am interested in, which sells a product that uses LEDs. But they want and arm and a leg for it. Can you figure out what they have done to make the "LED skin photo rejuvenating light"? I don't want to pay them $299.99 if it really cost $50.00 to make. I would also like the knowledge to build it, without making any friodes.
Paula
Answer:
What is the LED skin-photo thingummy-whatsit light worth? Um... very little.
The "NASA Study" they use as the principal source of support for their claims is pretty widely quoted around the Web by other people selling the same sort of thing, but if you actually read the start of the "Abstract" of that study you'll see that the only thing "NASA"-ish about the skin doodads is that they're using the same kinds of LEDs (which is to say, ordinary high-brightness red and infrared ones) as NASA used when studying plant growth in space. NASA then looked at those LEDs to see if they helped with wound healing, and such.
There is, as a result, a thing for warming injured parts of the body that may well work, but it's just a specialised sort of heating pad. There's also a thing for healing wounds that may have some utility; apparently red and near-infrared light does help a bit with wound healing.
NASA did not, of course, study the usefulness of LEDs for reducing wrinkles on people's faces. They put a lot of useless experiments up there to help justify the Shuttle and the ISS, but there are limits.
As far as I know, the red-light effect on facial appearance is limited to a bit of short-term "lifting", because it activates adenosine tri-phosphate (ATP) in skin cells - which is how it helps with wound healing as well - and accelerates the skin cells' production of collagen for a few days. Opinions differ regarding the magnitude of this effect. People selling red-light machines say it's enormous.
As has been said by many people over the years: There is nothing short of actual surgery or other skin-stretching gimmicks that actually gets rid of wrinkles permanently. Moisturising creams plump up the skin a bit for a while, but cheap creams that come in huge pump-packs work just as well as very expensive creams that come in tiny jars. All of the thousands and thousands of other devices and fads are a waste of money.
But yes, you could make such a device yourself (or have someone else do it for you) quite cheaply. It's just an array of red LEDs (various wavelengths are available cheaply), which is pretty easy for anyone who knows their way around a soldering iron to make. See the reply I wrote about LED grow-lights the other day for more info.
