Dan's Data letters #133
Publication date: 26-Nov-2004.Last modified 03-Dec-2011.
Cross-shaped peg, round hole
I have an IBM p275 21 inch CRT. I have been using this with a normal HD15 VGA cable. I am planning to buy a GeForce 6800 now, and I cannot for the life of me figure out which DVI cable to buy.
This page tells me that I need a DVI-A cable. My question is, which cable can I buy to use the GeForce's digital output with this monitor - DVI-A or D or...?
Aditya
Answer:
You can't use the digital output with that monitor; it's not a digital monitor :-).
What you're doing when you plug a CRT into a DVI connector is hooking up the larger extra pins in the cross-shaped bit on one side of the DVI-I connector. Those pins carry an analogue signal, just like a regular HD15 "VGA" plug, but there's still some reason to use them, because they're electrically superior to the old HD15 connector, which was never meant to carry a signal for today's high res, high refresh rate screens. You won't necessarily actually see an improvement over a quality HD15 cable, but the investment's small enough that you might as well get the DVI cable. You therefore want a "DVI-I" cable, which someone might call "DVI-A". I suppose, for correctness, DVI-A would be a cable that only has the analogue pins and conductors; DVI-I has both the digital and the analogue pins, and DVI-D has only the digital ones.
You can't connect the digital output of DVI to any CRT that I know of. It'd be possible to make a CRT with a digital DVI interface, but since the display itself is analogue, it'd be a bit pointless. "DVI-D" cables can only be used with digital-interface displays.
Turn, turn, turn...
I have a nice new digital camera that shoots respectable little video clips. Except that one of my first efforts, and one that I really want to keep, I mindlessly shot in portrait mode. So now if I play it back on my TV it is of course sideways.
I spent a whole Saturday afternoon Googling the Web for a free utility to either rotate or edit MPEGs, but no joy. Closest was a utility called VirtualDub that does the job, but then outputs an ENORMOUS (compared to the original) file in a format called AVI. I found lots of links to "avi2mpeg" converters on the Web, but all were broken.
Gave up in total frustration.
Surely with the millions of idiots like me racing around shooting MPEG videos with their digital cameras, there must be SOME utilities for editing MPEG files? One with all the functionality of VirtualDub would be great.
Neil
Answer:
VDub can save video in pretty much any format for which you've got a codec. Yes, it saves AVIs, but AVI is not a video
compression standard; it's just a way of packaging up video and/or audio that can be compressed with various codecs.
In this respect, it's the same as QuickTime video (MOV files). Windows comes with a bunch of codecs by default (check
out the Video -> Compression menu item in VDub), and there are plenty of others you can install yourself.
That's the good news. The bad news is that there's no way to avoid losing quality when you rotate an MPEG video clip and then save it as some other format, unless, as you say, you save a gigantic file using some lossless codec or other. All of the codecs that create video of a sensible size are lossy, and may work particularly poorly when recompressing video that was previously MPEG-compressed.
Desmokulator needed
I live in a house with people who do not like smoking, which is understandable since I too do not like smoke except when I'm on the other end. My question is, do these air filters that work by HEPA, or electrostatic sucking, or some metal in water, actually do anything? I want to sit in my room, smoke, eat, drink beer, watch TV, and not get pissed off people knocking on my door. I was looking at the Oreck purifiers, which seem slightly above reasonable price, but might be effective. They seem a little small to filter a room, 3.1 by 4.1 by 2.4 metres.
Also, has there been any real proof as to whether ionised/deionised/whatever air actually slowly helps or kills you?
Aaron
Answer:
HEPA isn't a technology, it's a standard for how well a filter cleans the air that goes through it. Practically no
particles bigger than 300 nanometres should be able to fit through a HEPA filter, which means it'll catch bacteria,
and some viruses, as well as dust. A HEPA filter doesn't necessarily do anything to catch smoke, because smoke particles
are generally smaller than 10nm, but many HEPA-filtered air purifiers are effective against smoke as well.
There are alternatives to replaceable-filter purifiers - electrostatic precipitators and ozone generators. An electrostatic precipitator is an "ioniser"; it charges the air near it (usually negatively) and encourages particles in that air to stick to the (relatively positive) casing of the precipitator, nearby walls, et cetera. Better ionisers have plates that catch most of the precipitate. No domestic ioniser works terribly well at cleaning the air of a whole room, though; even the ones equipped with fans just don't clean enough air per hour. And they get dirty. And, in answer to your other question, there's no reason to believe that breathing low concentrations of ions does anything much, health-wise, decades of ioniser manufacturer advertisements notwithstanding.
Ozone generators can neutralise smoke more effectively than ionisers, because they usually have considerable ionisation effect on top of considerable ozone output, and the highly reactive ozone oxidises the odour molecules it touches, de-stinking the smoke. You're talking at least a few hundred US dollars for an ozone generator that can keep a room decently clean, though, and you're likely to end up with a smellable amount of ozone in the air as a result. Ozone causes lung damage, and it starts doing it pretty much at the concentration where you start being able to smell it. Low ozone concentrations aren't an incredible ultra-poison for humans (they may be worse news for, say, pet birds), but this still isn't a brilliant solution for domestic situations.
So you're probably going to have to go with a filter of some kind. Fortunately, you don't have to buy a big-bucks commercial unit. Get a box fan - an ordinary white-plastic square-frame floor fan from an appliance store; spend some time finding a quiet one - and tape a big filter made for an air conditioner systems over it. The current favourite in this department seems to be 3M's "Filtrete" products, which apparently catch smoke well, and aren't expensive per day of use. They come in sizes up to 25 inches square.
No filtration system short of a howling-gale industrial clean room will magically delete all smoke from existence one second after it hits the air, but a big lazy fan with a filter certainly can very greatly decrease the concentration of smoke in the room while you're smoking (especially if you smoke near to the air purifier's inlet), clear the room quickly after you stop smoking, and pretty much eliminate the stale smell that comes from smoke particles sticking to all of the surfaces in the room (although adding a filter to a room that's already stinky is, of course, not going to help it).
Questionable Technologies, Inc
I found this site after doing some research after our company just had 3 laptops stolen.
Could you ask them for a review sample and give us your opinion?
Personally I think this looks like a crock, as there are no independent reviews, just the famous "testimonials".
Also, there is nothing a straight-up reinstall won't wipe, as far as I know.
[still another] Daniel
Answer:
I could ask for review product, but I doubt they'd send it to me; PC PhoneHome is, as you say, another one of those
odd products that nobody ever seems to have reviewed - not properly, anyway. It's been around in one form or another
for years, and something that does what it claims to do would be very useful, but those major computer magazines that
review every other single piece of commercial software that comes down the pike seem to have completely ignored it.
Even the PC PhoneHome site itself doesn't have anything but that handful of testimonials from people with no surnames.
But, whaddaya know, there's an affiliate program for people who just want to help sell it, never mind if it works or not. I've seen software like this before; see the second-last letter on this page, for instance.
This situation could have something to do with the fact that the claims made for the software are hard to believe - apparently it can not only determine the "exact coordinates" of the computer it's running on (OK, with the cooperation of ISPs you can get reasonable tracking information from an IP address, but it's not straightforward and you sure as heck don't get "coordinates"), but it can also survive not just an OS reinstall, but even formatting of the hard disk it's installed on. No technical information is provided regarding how this happens - one would presume it works like a boot sector virus, or something, but who knows.
According to the PhoneHome site, the software won a "Best Security Solution for Small Business" award at PC Expo 2002 New York; I can't find any independent verification for that, since pcexpo.com has mutated into something else and offers no past records. Another site suggested that the award was, uh, awarded by smallbusinesstechnology.com, but that's now a placeholder page hosted by an outfit that proudly advertises its "fast reiable [sic] servers".
PC PhoneHome also apparently won "Best of the Best in 2003" in SC Magazine's Mobile Computing category. That, you can look up.
If there is a Mobile Computing category, SC didn't consider it important enough to list on their site. I couldn't find any mention of "PhoneHome" or "Phone Home" on the scawards.com site at all.
But, lo and behold, PhoneHome has been tested by the magazine!
The reviewer gave it a glowing rating, but didn't actually seem to make any attempt to see whether the software, you know, works. Install PhoneHome, format drive, reinstall OS, let computer connect to Internet with no firewall or anything, ask the PhoneHome people to tell you what IP address you've got now. Sounds simple enough to me. Didn't happen, though.
Oh, and PhoneHome doesn't get a good rap here, either...
More LED lamps
You may, or may not, know about Enlux or their PopSci award.
Curtis
Answer:
I read about Enlux on Slashdot the other day, and
almost worked up the energy to post.
The Enlux datasheet for their "Neutral White" lamp quotes 300 lumen brightness - for 15 watt input, which may also be what gives the quoted 50,000 hour lifespan. At the actual 22 watt nominal run power, the light may be brighter but not last nearly as long. Not 22/15 as bright, though; more power means lower efficiency.
Anyway, a 65 watt halogen floodlamp can be expected to output more than 750 lumens, around 2.5 times as bright for around 4.3 times the power of the Enlux lamp at 15 watts. If you assume the Enlux lamp outputs something like 375 lumens at 22 watts, then a 65 watt halogen will give you about twice the light for about three times the power.
If all you need is the equivalent of a 30-watt-ish incandescent lamp, and if you're going to be running it for long periods, and especially if the lamp's somewhere that makes it very annoying to change bulbs, then the $US80 Enlux lamps are a great option. As general purpose illumination, though, they've still got the problems of other LED lamps.
Power saving definitely isn't a reason to buy Enlux lamps; if that's what you want, compact fluorescents can be had for floodlamp fixtures, and they give, as usual, way more light per watt than incandescent or white LED. They'll give you 900 lumens from 20 watts. They don't like being turned on and off all the time (in security light applications, for instance), but if the light's off a lot then power consumption isn't likely to be a factor anyway.
If you want coloured floodlamps, the Enlux lights are a much better option than incandescent, because coloured incandescent lamps are all miserably inefficient. They've got a regular incandescent filament with coloured glass (or just coloured paint over the outside of the glass) that soaks up most of the light. Coloured LEDs are considerably more efficient in lumens-per-watt terms than plain incandescents, and there's just no comparison with coloured incandescents.
Proof, schmoof
I know you're quite an authority on magnets... Do you have thoughts on some of the physical treatments that involve magnets?
I'm specifically interested in Magnetic Molecular Energizing (MME).
This is a treatment that is pre-FDA approval: see the this site and this other site for the Advanced Magnetic Research Institute.
Heath
Answer:
The AMRI description of what's meant to be going on here is pretty typical modern quack technobabble. Strong static
magnetic fields "improve chemical reactions", do they? OK, no problem; forget doing it to people, do it to a beaker
with some chemical reaction going on inside it instead - any reaction you like, with whatever particularly-susceptible-to-magnetic-fields
compounds you like, as similar or dissimilar as you like to the ones you allege are there in the body - and measure
how fast the reaction proceeds. And if it's any faster than it would otherwise be, collect your freakin' Nobel prize,
because ain't nobody else ever witnessed the phenomenon being claimed here.
The utter lack of basic empirical support for the basic empirical claims being made by these people, of course, does not preclude them from charging for the treatment. They're apparently charging fifty US bucks an hour, and that page also mentions that treatment sessions take at least four hours and a treatment program "generally lasts for two weeks". At one treatment per day, that's a minimum of $US2800. And if you go all the way "up to 150 hours", as they say, you're paying seven and a half grand. Half in advance, in case you wise up.
Since their treatment very probably does nothing at all (thereby providing them with some protection from charges of malpractice), and their machine does nothing but suck some electricity (assuming they actually bother to turn it on), and they provide no nursing care, food or cleaning, and charge extra for a "concierge" service, I imagine they're turning a decent profit.
"Research" organisations that charge people for unproven treatments are one of the time-honoured marks of quackery.
Regarding amripa.com... mmm. FrontPage templates, the unquestionable mark of a reputable organisation.
Their, uh, ClinicialData.htm page mentions that the MME is "IRB approved". Sounds good, means little. An IRB is an Institutional Review Board (I take all this back if it turns out that they're actually talking about the International Rugby Board); it's the portion of a medical institution that reviews the activities of the members, and among other things approves research projects. If your institution is the Revolving Bow Tie Institute Of Profitable Quackery, approval of your activities by whatever miscreants chose to be on the Board doesn't mean a whole lot.
The institution here is, of course, the Advanced Magnetic Research Institute, which as their "detailed driving directions" link points out, is some place which isn't actually in the exact geometric middle of nowhere, seeing as it's only a few miles from the bustling urban metropolis of Mocksville. Looks as if rent isn't much of a problem for their bottom line, either, eh?
The study they're talking about on that first clinical data page, by the way, has also not actually been published anywhere. They reference another a paper that was published in Neuroscience Letters at the end of the abstract, but PubMed doesn't list their own paper, or anything else that's been published by these authors. This applies to the other two abstracts accessible from that page; never published in even one of the dodgier journals Medline indexes, as far as I can see.
