Dan's Data letters #68
Publication date: 21 October 2003.Last modified 08-Mar-2015.
Double-headed audio
My computer is running Win2k with two sound cards; an SBLive 5.1, and a built-in C-Media CMI1738/C3DX. I also have two stereos, in different rooms. I'd like to plug in each of the stereos to separate sound cards, so that I can have the choice of either both playing the same thing, or both playing different things.
I've got the cables sorted out, but my problem at the moment is that Windows seems to be only able to output audio to one card at once through the 'Microsoft Sound Mapper'. Do you know of any way that I can get Winamp to play through both of the available output devices?
Eric
Answer:
I don't think there's an elegant way to make Winamp play back through both cards at
once.
(Well, I didn't think there was, until a reader gently pointed out the "Allow multiple instances" checkbox in Preferences -> Options. Duh. Unless you make actual mutliple Winamp installs, though, you'll have to change the output device for the second instance every time you run it - otherwise the two instances will both use the last saved settings and just play over each other through one output device.)
You can, however, use two different music playing programs - say, Winamp and Windows Media Player - and tell them to use different audio adapters.
I don't have a two-sound-card machine handy to try this out on, but I've done it with a PC using one sound card and one USB audio adapter.
To change the output device in Winamp, go to Preferences -> Output -> the output plug-in you're using (probably DirectSound) -> Configure, and change the Device in the drop-down menu. Winamp 3.x may do this a different way from Winamp 2.x; like all sensible people, I use v2.91.
Many players, including Windows Media Player, will use the default DirectSound device, which I think will probably be the last one you installed. You can change WMP's settings as well, in Tools -> Options -> Devices, which (for WMP9, at least) will give you a list of things WMP can get data from and send data to, one of which ought to be "Speakers" or "Headphones" or something. Double-clicking that item will give you a properties dialog with another drop-down output device menu in it.
The generally excellent Media Player Classic (ever wanted to play RealVideo and QuickTime movies in Windows without the appalling cruft of their official players? Install the official players to get the codecs, then use Media Player Classic to play the files!) also lets you do this, in Play -> Audio -> Options -> Playback.
In all cases, you'll need to close and re-open the player program to get it to play through the new device you've selected.
(A reader's now pointed out the kX Project drivers to me; apparently they let you map the rear speaker outputs of the SBLive to a separate stereo pair, making it possible to do tricks like this with just the one sound card!)
Tell-tale symptom
I'm having a really annoying problem with Windows XP not booting up. If my (Athlon XP 2600+) machine isn't plugged into the wall, or the power goes out, the BIOS resets itself to default options and then I get a message while trying to boot - "Missing NTLDR...". I cant get rid of this stupid problem and the machine won't boot.
I have tried the Recovery Console (fixboot and fixmbr) and copied NTLDR and NTDETECT from the CD to the hard disk in the console, but it doesn't do any good. Any ideas? I don't want to have to format the machine...
Chris
Answer:
If it always happens when the machine loses mains power, then it's a dead cert that
the problem is a flat CMOS backup battery. Modern PCs only need the backup battery when
they've got no mains input, or the switch on the back is turned off.
The backup battery for every vaguely modern PC, definitely including yours, is a lithium coin cell - probably a CR2032, though you could stick one of the thinner CR2024 or CR2016 cells in there if you had to. It's easy to spot the battery on the mobo - it's round, and silver, and in a plastic holder.
Get a new CR2032 from your local electronics store (or at a fat markup from a pharmacy) and swap it in, and you should be fine.
Automotive illumination
I'm a computer geek by nature, primarily hardware installation and troubleshooting, and I speak IDE, RAID, SCSI, PCI, and any number of other amusing acronyms, but I get a bit fuzzy when I try and work with ohms and amperage and wattage.
I also have a curious device that converts unleaded gasoline into motive power, and I recently discovered that a local computer superstore has begun carrying various "case modding" supplies, such as illuminated fans, chrome fan guards, cold cathode fluorescents, and some few pre-modded cases.
I've started drawing up plans for replacing the pedestrian dull green glow of my car's dashboard lighting, and the incandescent yellow of my car's interior lighting, with blue LED and cold cathode.
I was originally considering electroluminescent materials for doing this replacement, and while the flexibility of those items appeals to me, the relatively short lifespan does not.
I've got a rough decision to replace the incandescents under my dashboard (one in each footwell) with CCFL, and the lighting behind the dashboard (unknown, believed to be color-shrouded incandescent) with blue LED clusters.
My question to you is, what's the simplest and lowest-cost method of building a blue LED into a 12 volt system (that can range from 14.8 volts down to 11.5 during normal operation) that will not result in converting the LEDs in question into small incendiary devices, and might even support the dimming of those LEDs with the currently existing dimmer knob (which lowers voltage, I believe down to approximately "zero").
Nick
Answer:
The normal engine-running voltage for a "12 volt" car ought to be 13.8V, not 14.8; if
your alternator's delivering significantly more than 13.8V, you'll be boiling your battery.
There can be significant surges and spikes when you turn things on and off in a car, but if you set LEDs up with boring old series resistors to limit their current, and choose the resistor value so the LEDs aren't going to be pushed too hard even from 13.8V - 25 milliamps (mA) per LED, say - then you should be fine.
Let's say you set some nominal-3.6V blue LEDs up in series strings of two (which means your resistors will be dropping plenty of volts, which is what you want for maximum protection from overvoltage damage). Use the standard series resistance formula:
(Vs-Vr) / I = R
which means
(supply voltage minus LED voltage) divided by current in amps equals resistor value in ohms
and in this case you get
(12 - 7.2)/.025 = R
which means R = 192 ohms
...and 200 ohms is the closest standard resistor value to that.
The standard dimmer would work with this setup, though it might be more touchy than it was with the incandescents. Most dashboard light dimmers have pretty miserable brightness linearity anyway, though.
Physically mounting the LEDs is the tricky bit. The lights behind the dash at the moment aren't efficient (they're built for durability, not lumens per watt), but they're pretty bright, and you'll need at least a few 5mm LEDs (or one more expensive Luxeon or other high-flux LED) to replace each of them.
Getting the light where you want it to be with narrow-beam LEDs, or installing enough wide-beam LEDs (just sand off the top of the lens to turn any 5mm LED into a super-diffuse model!) to match the previous brightness, may be a complete pig of a job. Generally speaking, from my own experience, all work behind dashboards sucks.
Worth its weight in what?
While I was looking for a decent third party hard drive scanning utility, someone on the Atomic forums suggested "Micro-Scope". Now Micro-Scope seems to be well above and beyond your average HDD scan program. I've talked to the local Australian representative, and I've read a few reviews around the web on the "Ultimate Diagnostic Toolkit" that contains Micro-Scope and another seemingly magically wonderful product called POST-Probe.
The seemingly independent reviews here, here and here give it the thumbs up.
So while reading all this, my cynical-self reared up and said "what a crock of marketing, it may have a high hit rate but it can't diagnose EVERY damn problem all the time". And so I think of you. I can't think of any reviewing based site more independent and informed than yours, especially when actual electronics come into it (and not just benchmarking proggies).
I run a support business. If Post-Probe and more importantly Micro-Scope can quickly and easily find hardware faults without the usual swapping crap in and out and running various test programs like MemTest, well, that'd be peachy. It'd be a huge time saver. It'd cut down massively on training I'd have to give employees on hardware. And it'd be worth the price tag ($AU1550 inc tax for the Toolkit, $AU880 for Micro-Scope alone, $AU770 for POST-Probe alone).
So I seek your opinion, oh holy master of Zen.
Jack
Answer:
Micro-Scope is one of those products that's so horrendously expensive that practically
nobody selling it seems game to list its price.
This place has the full
Diagnostic Toolkit for a mere $US763.20 (about $AU1100 at the moment); I had to look
at about ten other no-prices vendor sites before finding it.
I see no reason to suppose, however, that Micro-Scope wouldn't be useful for the jobbing computer tech, who frequently has to troubleshoot mysterious problems and hasn't the time to do the usual shotgun debugging routine; even if you use it only weekly, it could pay for itself soon enough. To be fair, though, the makers don't promise that it'll detect every problem.
If your workload contains a lot of brand new tweaky machines, it's possible that Micro-Scope won't work too well for you. I doubt Micro-Scope can accurately reproduce the system load of playing a 3D game, for instance, and it certainly won't find any software problems, since it runs its own special OS to do the tests.
If you mainly work on older systems, though, it could indeed be good value.
Micro2000 have been selling versions of Micro-Scope for at least ten years now; it's presumably pretty highly evolved, and the paucity of independent information on the Web about it is partly because it's so darn expensive, and partly because the only people equipped to properly review it are too busy doing the work which makes them so equipped. Despite my best efforts, I don't have enough dead computers here to review either of the Ultimate Diagnostic Toolkit components properly.
POST-Probe is just a POST diagnostic card, but it does look like a pretty nifty one - ISA and PCI in one unit! If you only need a PCI POST card, though, I think you could make do with something cheaper.
More free speakers!
In regards to the "Free speakers!" letter from the last column - yes, this is the case in Canada. In fact it meant that I was able to get another set of 4 satellites for my Z-560. (The dealer used it as a means to recover his warranty shipping costs - $CA50 for four.)
I have put them through some hell, and I thought I might blow one or two, so having extras seemed like a great idea.
Would you believe they work pretty well as BAND MONITOR speakers during a live rock band performance? I had two of them on the floor pointed up at me while doing vocals, with a 110db+ set of drums 2 feet behind me. Note: If the phase plugs get hot to the touch, give them a break! None have died YET!!
Then another idea hit me. I have an Audigy 2 card - it supports 6.1 channels! I added an old amp to the setup, plugged into the Rear and Front Center channels on the sound card, and added two more satellites to the pile! After balancing and calibrating, it sounds REALLY good! Although I AM wondering if the 6.1 benefit is really there... OK, games will use it...
Still have two extras though! Those things make AWESOME surround speakers. Shielded too, so center is possible also.
The issue will probably come up - why all this talk of Z-560 warranties? Is there a problem? Yep - there is. Those subs are real suckers for punishment, and people tend to beat the SNOT out of them, not being aware that they are being over-driven...
Phil
Answer:
My original correspondent has also now confirmed
the free-Z-560-speakers situation in Canada, after a skeptical reader from the USA asked
me if it was really this neat a deal.
I don't know whether everybody in Canada who has something warrantable go wrong with their Z-560s will end up keeping all of the speaker boxes, but it certainly seems to be far from unknown.
(Nobody tell Alex.)
I can believe that the Z-560 satellites can endure a lot of abuse; they've got proper drivers made by Tangband, not the usual no-name Chinese super-cheapies.
Monitor speakers, especially little improvised ones like these, are generally driven a long way into distortion; everything else is so loud that it's hard to notice it, though. Since these ones don't have any tweeters to burn up, and since they do get considerable extra voice coil cooling from the phase plug, I can believe that they can handle it without complaint.
People having trouble disposing of extra Z-560 satellites should note that since they've got plain old eight ohm drivers, they'd not only work fine as not-much-bass bookshelf speakers, but could also be teamed up with a cheap standalone powered (pseudo)sub to make another computer sound system. The auction sites teem with awful "multimedia" three-piece speaker systems, which can be rendered considerably less awful by swapping their near-worthless satellites for something decent like the Logitech pair. It's also not hard to find somewhat better powered subs as separate products, second hand or new from decent electronics stores.
As regards the hard life endured by many Z-560 subwoofers operated by people for whom too much bass, at any distortion level, is barely enough - I think the speaker system's bass-heavy design is definitely targeting this section of the market.
Tiny tankitude
It would appear some models of the Digi-Q tanks with revolving turrets are now available.
Would you be kind enough to tell me where I can get them in Australia?
Jayson
Answer:
Sorry - I don't even know who (if anyone) sells the old Digi-Qs in this country!
EBay's an excellent source, though. For instance, the same Japanese dealer who sold me my Digi-Qs has rotating turret ones now.
Pleasingly, you don't need to buy new controllers to use the new tanks; you can just buy the tanks by themselves, and use them with the original transmitter/chargers.
FZAT!
I've seen video clips of a professor who sends model rockets into the sky with a thin wire attached to it to induce a lightning strike. That gave me an idea - take a steam boiler filled with water that has a large metal rod through the middle of it. That rod would be made of the same materials that your stove top burner is made out of. One end of the rod is connected to the wire or method of inducing a lightning hit, then other end of the rod is connected to a heavy cable that is grounded. Upon initiating the lightning strike, the bolt travels through the rod made out of high resistant metal and then to the ground.
Wouldn't the lightning's current heat the rod sufficiently to create quite a bit of steam, which can then be harnessed to generate electricity? Obviously the boiler would need to be insulated to some extent to force more current through the rod.
A spin on this idea is not to use a model rocket with a wire, but to use the patented method of shooting a laser beam in the UV range that creates a trail of ionized air which can also induce a lightning strike. I live in a part of Colorado that has many lightning strikes every year.
Nathan
Answer:
If you made a high-enough-resistance path to ground that it worked as a heater element,
the lightning would probably just go somewhere else, like through the air instead. When
you've got enough megavolts, everything conducts.
The other problem with this idea is that assuming your Young Frankenstein Starter Kit does give you some way to transfer a significant amount of a lightning strike's energy into a boiler, you're going to have a very hard time stopping the boiler just exploding instantly.
Lightning strikes are usually quoted as having one to ten billion joules of energy in 'em, and they deliver it in a scant few milliseconds, at most. This presents a very large power-handling problem, since things that deliver large amounts of energy in a millisecond or three are generally referred to as "explosives".
One gram of TNT, for reference, is good for 4184 joules. A TNT-powered hand grenade will have 100 to 200 grams of the stuff in it - 600,000 joules, say. A stick of dynamite is good for about two million joules.
So even if you manage to capture only one per cent of the energy of a mere one billion joule lightning bolt, you've got about five sticks of dynamite going off in your boiler. Let me know how you get on with that.
More practically, you could use a capacitor (the size of a building...) to store the energy. Unfortunately, you'd still have a hard time gathering enough energy that way to make even a modest effort, let alone the purchase of a billion dollar cap, worthwhile.
Here's a page on this very subject, and here's another, from one of those boring "please don't spectacularly annihilate yourself" killjoys.
