Dan's Data letters #82
Publication date: 29 Dec 2003.Last modified 03-Dec-2011.
Hot discs
I like to burn my own CD mixes and listen to them in my car CD player on my way to work. Since I tire of listening to the same CD, I found myself burning a lot of CDs and never using them again. Recently, I started to burn songs on a CD-RW instead of CD-R, so I can rewrite the disc when I grow tired of the songs. I ran into an interesting problem. When I play them in my car in the morning, they are fine. When I get back into the car after work, the CD player doesn't recognize my CD-RW. But if I'm in the car with the air condition on for about 10 minutes, the CD-RW plays fine.
This leads me to believe that the temperature of the inside of the car has something to do with the CD player's problems with the CD-RW. I should mention that I live in South Florida and I park outside, so when I get in my car in the afternoon, the inside temperature is in the upper 90s or lower 100s Fahrenheit. The CD player plays other CD-Rs fine.
My hypothesis is that the temperature in my car is above the operating temperature of the CD-RW, but within the operating temperature of the CD-R. I know that when you burn a CD-R, part of it is gone forever, but with CD-RWs, it somehow just changes state? Maybe the heat is causing it to do that?
Daniel
Answer:
You may be shortening the life of both kinds of disc by leaving them in
a hot car, but they're not getting to their writing temperature.
I'd lay odds on this problem actually being caused by the CD player getting too hot. It's harder to read CD-RWs than it is to read CD-Rs (and, in turn, harder to read CD-Rs than it is to read pressed CDs), so in a particular temperature range the player can read CD-Rs but not CD-RWs.
The phase-change temperature for CD-RWs is around 600 degrees Celsius; the crystallisation temperature's down around 200. Fortunately, your car isn't managing either of those.
Here's a reference.
Slow and slower
I recently obtained (for free, of course) an old Voodoo Banshee PCI video card (Skywell Magic TwinPower, if you want the brand) with 16Mb of SGRAM, from a friend who was scrapping his old machine. My current card is an SR9 8Mb AGP card not from Heckler and Koch or Sony, as a Google search seems to indicate, but Number Nine Technologies (don't blame me, it's my first machine, and was purchased by a family member from Harvey Norman several years ago along with a system based around a P3 450).
I plan on upgrading as soon as I have the cash, but until then, it would be nice to know which card I would be better off running. Is an extra 8Mb on the Voodoo Banshee going to make any real difference, especially from a PCI card, or should I wait until I have the money to get a new machine?
Luke
Answer:
The Voodoo driver situation for NT-based Windows versions (2000, XP) isn't
good. There are third party drivers, but no official support.
The Banshee wasn't an exciting card even when it was new, though - and that was more than five years ago!
Your Number Nine SR9 is a Savage4 board, likely to be a bit faster than a Voodoo 2, which is in turn faster than a Banshee. The memory may make a difference if you want to push the envelope for 2D resolution, but fiddling with these cards is generally pointless; the difference between "ghastly" and "merely awful" 3D performance is not worth any effort at all.
All of these cards are ancient history these days. TNT2 M64 cards (not quite as ancient) are going for ten Aussie dollars (plus delivery) on eBay; a Banshee might be worth about $AU3.
So yes, you should just save up for a new machine, or at least a "new-to-you" one. You'd probably find a nice cheap used 1GHz-ish system with a GeForce3 to be fast beyond your wildest dreams!
'Pod toasting
I plugged my (own personal) iPod into the FireWire port of my (work) Macintosh G5 and noticed it was getting rather hot, so I unplugged it... no harm done. This is my second iPod, though, and looking back I do believe I had the first one plugged into the very same G5 for a short period before its demise.
So I cut open a FireWire cable for testing, and found that the G5 is putting out 25 volts, while the generic PC next to it is putting out 12... that sounds bad, although from one of your articles I learned that FireWire can put out up to 40. I don't know anything about electricity except that it makes me nervous.
So I'm confused; did that G5 kill my poor iPod?
Dave
Answer:
It certainly shouldn't have.
Yes, FireWire can deliver up to 40V, but it's supposed to throttle itself to whatever the connected device asks for. This is in contrast to USB, which can deliver any voltage you like as long as it's 5V.
The ceiling voltage for FireWire depends on the controller; 40V is just the maximum in the specification. I don't know how many FireWire controllers can actually manage 40V (I think most, if not all, PC controllers top out at 12V, because they're unable to step up the 12V they get from the PSU). I also don't know whether any FireWire devices actually want 40V.
In any case, no iPod should be barbecued by a FireWire connection. There may be some bug here that I don't know about, but stuff like this tends to get lots of publicity, whether it deserves it or not (witness this and this...), so I think the death of your previous iPod was just coincidence.
You can expect an iPod to run warm when connected to a computer, partly because the battery's charging but also because (as I understand it) it spins its hard drive then - it expects to have to handle data transfer at any moment. Hard drives, even teeny little iPod ones, run warm thanks to friction between the air inside the drive and the spinning platter.
If you charge an iPod from a plugpack, it won't spin its drive and won't warm up as much.
Power horror
I live in a house that experiences bad power surges. It's blown our dishwasher twice, resets my computer for no reason at least once a day, and we blow light globes like there is no tomorrow. The electricity company came a while ago and turned something down, and that stopped the drama for a while. Yet, a few weeks ago my poor beloved brand new computer left this earth for Silicon Heaven. Same problem.
So, I'm asking you what brand/type of UPS I should be looking at purchasing for my replacement computer? It's a bit of a bitchen' beast, P4 3.2, 3x160Gb SATA HDD, Radeon 9800XT etc etc and 400Watt PSU, so I guess it draws a lot of power? I need it to stay up for as long as possible, maybe 30 minutes at least. My budget's up to $AU1000.
Marty
Answer:
Point 1: If you want the best protection from bad mains power, a line conditioner
will give you better protection per dollar than any UPS. It won't give you
the ability to ride out power cuts of more than a second or three, though.
Point 2: Cheap UPSes (which are all actually Standby Power Supplies, as I've mentioned before) probably won't cut it. They're good enough for most purposes, but their power filtering is pretty ordinary, and probably won't meet your needs.
So you're probably going to need a big-brand UPS. It's possible you'll be able to find one of those in your price range, or only a couple of hundred bucks above it.
Go to the APC site, tell it you're in Australia, and then use the Selector to see what they offer to suit your PC. They're not the be-all and end-all of UPSes, but I'm pretty sure their filter hardware is better than what you get in, say, a cheap Opti UPS, and they've got a big product range with various off-the-shelf expansion batteries, which'll make it easy for you to extend your run time.
Batteries, and me
Quoting from this column: "In a cell or battery that's delivering current, the cathode is where reduction is taking place, sucking up electrons and making the terminal positive, and the anode is where oxidation is taking place, spitting out electrons and making the terminal negative."
Alrighty, this seems confusing enough as it is, but if the cathode is "sucking up electrons" surely it is becoming more negative given the negative charge on an electron? Likewise, a terminal "spitting out electrons" would have to become more positive...
BTW are you the same Daniel Rutter (how many are there really...) that wrote for ACAR all those years ago? :)
Jonathan
Answer:
Yes, you can think of the anode/cathode difference that way - but taking
electrons from whatever touches it (including the metal plate over the end
of the battery) is what a positive terminal does; that which touches
it gains a positive charge.
Dwelling on the Zen of the terminal's own identity is something best left for the years after one turns 150, in my opinion.
How many Daniel Rutters are there? Well, as I write this, hits one through seven in a Google vanity search are all me. Hit seven has someone saying he wishes he were me. You have to go to the second page of results before you get away from me.
Excuse me while I buff my fingernails on my shirt-front.
And yes, I did indeed write for Australian Commodore and Amiga Review, back in the day. This comes up every now and then.
The Swiss Army Hand Grenade
I wonder if it's safe to keep the Victorinox SwissFlame you reviewed in the car, fully charged with its butane gas, in the Australian summer? A tool that burns, prods, opens and cuts would be invaluable for any car - but is it safe to store in the glove box?
I already have a CutCo pocket knife attached to my key-ring which offers saw and straight knife blades as well as scissors - a bulkier pocket knife is not my want, but the Victorinox SwissFlame is without a doubt something I need in my car. Even if just to say "I have one..."
Steve
Answer:
I'd say it's fairly safe to store a SwissFlame somewhere hot, but
I wouldn't be entirely confident about it.
Butane lighters certainly can cause fires and explosions if they get too hot, though there has to be an ignition source to make a ruptured lighter really dangerous, and piezo-ignition lighters like the SwissFlame are very unlikely to spark if they burst.
I've no idea whether the SwissFlame actually would burst in a hot car, but I doubt it. It looks far too strongly built to me to be likely to fail catastrophically at only 70 degrees C or so. I think most refillable lighters have filler valves that fail elegantly under overpressure and let the gas out slowly (disposable lighters can be a different story); the SwissFlame would probably do that if severely overheated, rather than go pop.
In any case, slow leakage from a butane lighter in a car will only cause problems if you're unusually unlucky - you'd probably get away with having a whole can of butane rupture. Butane's heavier than air and will puddle up wherever it can, but a lighter-worth of it that happened to be puddled in the footwell of a car (assuming it couldn't just leak out somewhere) would probably be ventilated into harmlessness by anyone who opened the door.
Butane also doesn't have a wide explosive mixture range in air (unlike petrol vapour...), so even if you do manage to light a butane puddle, it'll very probably just go whoosh and burn off relatively peacefully, rather than knock the windows out of your car.
Here's a reference about this.
Cavalcade of questionability
Have you considered reviewing these products?
John
Answer:
I hadn't seen the SSUBA page before (neat
- breathing apparatus and perpetual motion machine all in one!), but the
Alien Technology Online Catalog,
as you may already know, is one of several pages created to taunt the
unhinged time
travel spammer.
Mighty midgets
Do lithium ion AA batteries exist? If so, where? If not, why?
Max
Answer:
No, they don't. This is because the lithium ion rechargeable chemistry produces
3.6 volts per cell; you can't make a lithium ion battery that delivers less
than that.
Non-rechargeable lithium AA cells develop 1.7 volts per cell, which makes them broadly compatible with gear that expects 1.5 volt per cell AAs (and which will generally also run fine from 1.2V/cell NiCd or NiMH AAs). But that extra 0.2 volts per cell is about as far as you can stretch it. Someone may well make LiI cells that're the same size as AAs (the cells used in laptop batteries are often the larger "4/3A" size), but they won't be interchangeable with them.
Also, lithium ion is very touchy about charging. If you manage to connect a LiI pack to a charger that's made for some other battery chemistry, you'd better keep your fire extinguisher handy. Packaging LiI batteries like any other kind of rechargeable battery is therefore a Bad Idea.
Fuzzy footwear
As you may or may not be aware, your area of the world produces the finest and most comfortable boots in existence, by the name of Ugg (well I'm sure you are aware of that, but the next part, I am not sure of). They have now cleverly produced a "Baby Pink" colour with which to drive the market into a boot-buying frenzy. Their plan has worked. It is currently next to impossible to acquire said boots in the USA, without paying several hundred dollars on eBay for size 12+.
I cannot afford such luxuries, as I am a poor college student.
Are these boots also equally impossible to come by in their native land?
I remember when my father (in the navy) had a brief stop-over in Australia and said that the boots were everywhere. I have no idea if the women of down under have equally ravenous hunger for all things Pink and Fuzzy.
Matt
Answer:
Sorry, but nobody I know would be seen dead wearing pink Ugg boots in public
- or any Ugg boots, really.
Your dad wasn't lying; Ugg boots are everywhere in Australia. But you won't see people wearing the things. In Australia, even a brand new pair of Ugg boots has the sartorial cachet of a very old pair of tracksuit pants and a singlet with holes in it. Worn by someone with a mullet.
Lots of people own Uggs and slob around the house in them in winter, but nobody who doesn't keep a pack of cigarettes in their T-shirt sleeve is likely to consider them acceptable to wear for anything beyond a trip to the corner shop to buy some milk on Saturday morning.
For this reason, the sudden discovery of Ugg boots by fashion victims in the USA a few years ago was a source of great amusement to Australians.
Anyway, maybe some people own black ones; every pair I've ever seen flopped in the corner of someone's bedroom has been natural beige, though. Pink Is Right Out.
It's possible the pink ones never even made it to Australia, since the Ugg company is actually about as Australian as Outback Steakhouse (observe the whois info for uggaustralia.com...). There are Australian manufacturers, but I don't think they have the "fashion" range of the US company.
(Belated update: Blue Mountains Ugg Boots sells very good Australian-made boots, and will ship overseas in case you don't live very near Faulconbridge. Overseas customers should bear in mind that Australian shoe sizes are not the same as American or European ones. They are not paying me for this endorsement, but I am wearing my pair of their boots at this moment.)
