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Comment: Re:If it sounds too good to be true (Score 1) 243 243

NiCd starts at 1.2V. But nobody (should be) use(ing) those any-more. My experience is that most good NiMH cells start at 1.4-1.5V and maintain 1.25V during most of their in-use-time.

It shouldn't be too hard to switch on the boost circuit this Batteriser supposedly has, only when a reasonable current is drawn by the device. A current sensing circuit should not add that many components. That should prevent the Batteriser from drawing power to keep the boost circuit running when the device is switched off...

[edit]
-Unfortunately I'm unable to show you the ASCII art I had made... So here is a description of it:
Main circuit, in series: +bat --[>|-- [R2] - device - -bat (ground).
Booster circuit, 4 leads: on both sides of the diode, ground and Current detection sense input.
Current detection circuit, 3 leads: on both sides of R2 and Current detection sense output.
[/edit]

Something like this (just a rough idea. I'm a radio amateur, not an electronics engineer): R2 is very small and in series with the device (and the battery). Current is sensed over R2. A diode (pref. a low drop one) maintains most of the original battery voltage over device as long as little current is drawn. When boost circuit kicks in, voltage is boosted, the diode prevents the surplus voltage from running back to the input of the boost circuit. Drawback, R2 will dissipate some energy and its resistance depends on how sensitive you can make your current detection circuit. Also, the current detection circuit itself may use some energy but if devices with a 'soft' standby can be battery powered and drain the battery in a matter of multiple years instead of days (I'm looking at calculators and those small bike LED-lights), so can this Batteriser.

There is only one sort of device I can think of which may not be able to deal with this. I know some devices that have a stand-by current in the micro-ampere range that still do need a rather high supply voltage, else they reset, restart, draw lots of current while restarting and then go back into stand-by. If the booster circuit shuts down while they are in standby, it would mean and endless cycle of restarts, draining the battery even faster. Of course those devices already would drain the battery faster in the original situation. When the battery voltage would become low the first time, the device resets. Then because of the internal resistance of the battery, the voltage would drop even more by the current drawn by the start-up sequence.... resulting in a reset ... rinse and repeat. A boost circuit should have a capacitor at the device side of things (if only to smooth out the high frequency noise from the boosting). If you can make it rather large (in capacity) and have a voltage sense circuit over it that turns on the boost circuit on for a bit if the voltage drops under, let's say 1.4 volt, maybe you can remedy that problem. But how much room is there for a supercap in such a small device as the Batteriser?

Comment: Re:No morning coffee yet (Score 3, Informative) 76 76

In a floppy disk drive there is a stepper motor which drive the read/write heads. That mechanism is used in normal operation to select the correct track/cylinder to read from/write to (a floppy drive is much like a modern hard disk drive in that respect, except the information density is way less and the 'disks' are of course portable).
In the instance of this musical instrument/organ it's 'abused' by letting the stepper motor step with the frequency of the tone you want to play. The friction between the read/write heads and the rails they are gliding over makes the whole floppy housing vibrate a bit with the selected frequency. The housing acts as a resonance box and the vibration is transferred to the air where it produces sound waves in a frequency (the same the stepper motor vibrates with), you can hear.
Because the stepper motor doesn't rotate smoothly but in steps (hence its name) the produced sound is rather 'sharp', 'blocky', or whatever you may call it (I have some difficulty here finding the correct musical jargon - English is not my native language). There are a lot of higher harmonics in it.
Maybe if you saw the video in the original article, you noticed some random gaps in some of the notes played, where, if you knew the pieces played (they are rather popular numbers so I'll assume you know at least some of them), you would expect the note to continue. Those are caused because the head has reached the end of the track and now has to reverse (and so does the rotation direction of the stepper motor). That takes a moment in which no 'music' can be played.

Comment: Re:Make a federal case out of it - learn this term (Score 4, Interesting) 42 42

I already think of myself as European. I'm Dutch as well, by the way. There are many more who think the same. There are also quite some people who do not. European integration is already at work for at least half a century. With mixed results, I have to admit... but one thing it did do right; 1945 was the last year there was an active war between European nations (there has been quite an ugly civil war (Yugoslavia) and Russia doesn't seem to play nice, recently. But France, Germany and the U.K. seem to have lost their imperial aspirations). Let's hope people are smart enough to see the benefits and be wary of things that should be better - and keep voting accordingly.

Comment: Re:Looks like a shipping container, with a roof (Score 1) 71 71

Well ... it should weigh less than 100 KG (200 pounds?)... I don't know of any shipping containers that light. The smallest 'common' shipping container according to the wikipedia website (20') weighs at least 22 times as much. And it should handle heat/cold a lot better than a big metal box.

To me it rather looks like other 'usual' temporary housing things. Those white houses they set up at big outdoor events. The only one that comes into mind close where I live, where I've seen them and an event with (quite) some international renown are the yearly 4-day marches (in Nijmegen, the Netherlands). They have a number of those houses (a big one and some smaller ones) at the start/finish site, for example where medical personnel can treat people with feet problems caused by the long walk. Only, those are not insulated at all... just made out of white plastic segments and a sheet roof.

Comment: Re:Obvious Usefulness (Score 1) 157 157

Only... we already have kind of natural light houses for galactic-scale navigation already. In multiple types even.
Pulsars (fast spinning neutron stars) are the first that come to mind. Their pulsating frequency seems to be very stable which makes them easily recognizable and distinguishable. There are multiple in our own galaxy (of 14 of them, their characteristics were depicted on the Pioneer Space Probe plaque. One of 'our' early 'Hello, aliens' attempts). They should be perfect for intra-galactic travel. Pulsars have also been observed in other galaxies but for inter-galactic travel I would rather use... Quasars.
Quasars are like 'very distant' radio beacons. With 'very distant' I realy mean 'very distant'. The scientific consensus is, quasars are compact regions in the center of massive galaxies surrounding a central supermassive black hole. The signal they emit comes from the perpendicular jet of energy released as matter falls into the super massive black hole from its accretion disk. The emission is extremely red-shifted which makes them for us, 'light up' heavy in the radiofrequent part of the spectrum and gives us the impression of them being that 'very distant'. Their position shouldn't move a lot, while you travel to your vacation home in the Small Magellanic Cloud.

Comment: Re:Because capitalism, idiots. (Score 5, Interesting) 245 245

This (for quite a part) USED to be government work. Half/3 quarters of a a century ago, at least. Research, also into medicine, was university sponsored work and universities mainly got sponsored by government (at least in large swaths of Europe.... don't know how it was in the '50's/60's/70's in the U.S.A.) However in, 'first world' nations, those that actually 'have/had' resources to develop new drugs, things got privatized, subsidies got cut down because government spending had to be cut down because of .... because Republican/Liberals/howeveryouwanttonameit. Result: Drugs are left to the market and so only what the market sees as profitable gets developed.

Perfect, if you really like it that way, and according to election results, a lot of people in the developed nations think it's all roses (pun intended).
I'm not someone wanting everything and our lives state owned but I do vote socialist. Just because I see, time and again (and I'm not even fourty...), things the free market can not solve. Even in a 'perfect' capitalist system. Which, I'm afraid, we have not one of, in this world.

Public transport, Medicine, Communications/utilities/transportation infrastructure (emphasis on infrastructure, not services), Fundamental research/sciences, Nature development...
Some things you should do as a community, others you should leave to the free market.

And be damned, pay your f*cking taxes, all of you! Also the rich. Yes, I'm looking to you too. You should get enjoyment from living in a country where things are arranged properly. Your investments are worth double if you don't have to fear the troubles that come when a significant part of your fellow human beings live below the poverty line. Your spending into security should be insignificant in a well managed nation... How much extra does that dwelling in a gated community cost you? Talk about living in a cage...

Comment: Re:Solution: Decouple wired buisness from company (Score 1) 255 255

(Disclaimer: A small part of the hyperbole in this post is because of fun. The rest, sadly, is the honest truth.)

Hey! That map only includes HALF of Europe!

You forgot 90% of the Scandinavian peninsula including the entire territory of Finland (I'll forgive you for not adding Iceland and the Baltic, small as they are) all of which have excellent internet services. Then there is a bunch of European countries at the east side which, at least, have internet options comparable with those in the U.S. (sad but true): Greece, Slovakia, Slovenia, Romania, Bulgaria, Poland... If I would be really anal, you should include Belarus, the Ukraine and parts of Russia and Turkey as well. Try to lose that!

Also Sweden isn't roughly the size of California... it's California-and-a-half, having 1/4th the number of inhabitants and a climate more akin to Alaska. It should be MUCH harder pulling off a high-tech internet infrastructure there. But instead, theirs is amongst the most advanced... in the World.

The most preposterous argument is that of total U.S. land size that limits your abilities to provide internet access to most of your population. As if 99% of your population lives in the desert (don't make me laugh; you're not Saudi Arabia, not by a long shot). You have States, haven't you? And you Americans are proud tot let States do what States should do, and Federal government what only Federal governments can accomplish. Printing dollars is Federal. Nuclear weapons, that's Federal. Education, that's State business, as is Transportation. Why isn't providing basic utility services (like internet access) as well?
Here in Europe, many countries are united in the European Union. That European Union has regulations regarding these sort of things. But they aren't set in stone! Each country does its best to implement them, in a way that suits that country best. In that regard, it isn't (or shouldn't be) that much different than the U.S. and its 50 states.

And don't get me wrong. Over here, almost everyone thinks of internet access as a basic utility service. Like running water, electricity, gas... If you're (self) employed or if you run a company it's even an essential service. You couldn't do your taxes otherwise. And every year more local/state government-populace interaction (like requesting permits, applying for identification papers, driver license) is available on-line which saves... tax dollars/euros as less paper mail and administrative personnel is needed to get that work done. That should warm at least every Republican heart. Less taxes because of a more efficient government!

I'm surprised you Americans haven't already started a class-action lawsuit against the big teleco/cable companies for wilfully limiting your freedom of information rights (part of freedom of speech). How can you guys keep yourself informed if you have to crawl every part of the (information high-)way? They seem to actively hamper the development of high speed internet access by not investing in their networks and using their monopolies to prevent healthy competition. It's so un-capitalistic I'd be sick about it! You should be screaming your discontent off your rooftops and use those four boxes you're so proud of having (soap-, ballot-, jury-, ammunition-, in that order). We only have the first three here... you should be more free than us, not the other way around!

Comment: Re:Hope it has GigE. (Score 1) 180 180

Probably a combination of:

1) High bandwidth consuming action scenes (actual bandwidth demand can fluctuate quite a lot over the runtime of a movie)
2) Not enough buffering (I guess that primarily depends on the media playing software)
3) Congestion on the WiFi channel (neighbour(s) also streaming video... and even if you can't find another SSID doesn't mean there isn't another non-WiFi appliance or a 'silent' WiFi using that bandwith and your access point has to 'packet switch' around the nuisance... )

Never choose WiFi over wired unless you really (it's less reliable), really (it's less secure), really (it consumes limited resources) have to.

Comment: Re:Cyptowall is very sophisticated (Score 5, Informative) 181 181

First, the machine pulling backups has completely different interaction with the 'world' than your average system-to-be-backed-up. I assume you're not reading e-mail, PDFs or surf the web on the system you use for data backup. Also, it should not execute any of the data it's backing up so the actual backup process should not be an attack vector for malicious software.

If you still want more security you could choose for the machine pulling backups to actually have a different hard and/or software platform than the machines it pulls the backups from. For example, you could have windows desktops and shared SMB partitions that contain the stuff to be backed up and a Linux NAS with Samba client doing the backups using a cronjob. Make sure that, if the NAS does have Samba server as well (for network shares) your backups are not available through them because, as we know of Cryptowall, it will also encrypt network data the infected system have write access to.
There is virtually no malicious software that can infect multiple distinctly different hard / software platforms in the same attack. Although in this particular instance (Cryptowall 2) it does make use of two processor architectures, x86 and AMD64 to do its things...

Comment: Re:Wrong conclusion (Score 1) 269 269

My Creative Zen Xtra (2003) is still going strong. 30GB harddisk (also available in 60 GB), large blue-backlit LCD, excellent user interface, IMHO. Replacable battery, however the Li-ion cell it came with is still doing what it's supposed to do. Built like a brick, however the front aluminium cover which gives access to the battery compartment hasn't got the sturdiest of closing mechanisms. Not a 'scroll wheel' of course because that was patented technology at that time. But side buttons and a jog wheel for volume and selection works for me.
I did install the 2.10.03 'plays for sure' firmware to make it WMP 10 compatible. Apparently that didn't always work out well for it has a reputation as "Zen killer". But I never had any problems with it...

I also still have (but don't use) my Creative D.A.P. Jukebox (Disc-man sized, blue/silver, 6GB HDD, pre-ipod era). Fond memories... but 6 GB is just too small.

Comment: Re:Outages happen! (Score 1) 516 516

Here in the Netherlands, years is stretching it a bit. But -a- year should be easily doable. This year I know of one occasion I had to re-set my alarm clock due to a power outage not of my making (as a hobby electronic / radio amateur I do trigger the automatic circuit breakers sometimes). Regional power outages lasting longer than a couple of minutes make the national 8 o'clock news as major news items - they are that rare but they do happen a few times each year.
Last time we had a major power outage in a region near me (a few larger villages had no power for a couple of days somewhere in december 2007) was when an Apache helicopter flew into a set of HVAC lines (50KV, I think). It was on one of the very few places in our power grid there is no loop in the network, which is why it took a few days to restore the power for those villages, instead of seconds.
The thing I noticed when the accident happened (it was a Wednesday evening and already dark) were the lights flickering for a couple of seconds and I made a remark to my dad about something big probably shorting out. My dad, now retired, worked for KEMA at that time which, amongst other things, tests high voltage equipment for power grids, which might explain my interest in the subject as well. Later that evening, when I got home I heard about the helicopter accident on the re-run of the national 10 o'clock news.
The helicopter made an emergency landing and luckily nobody was harmed.

Comment: Re:Tell me why I should care. (Score 2) 75 75

This part of the text is where you should start then (By the way, I am certainly not a physician, just interested, as you are):

There are 35 blood group systems, organised according to the genes that carry the information to produce the antigens within each system. The majority of the 342 blood group antigens belong to one of these systems. The Rh system (formerly known as ‘Rhesus’) is the largest, containing 61 antigens.

The AB group is the earliest discovered (?) blood group system. The Rh group another (that +/- thing you were taught is an extreme simplification of it and points only to one antigen from the complete 60-odd set of Rh antigens). And there are 33 more blood group systems, apparently. I knew there was more than AB and Rh but I didn't know there were that many myself.

Start on some Wikipedia pages first. A lot of information is pretty accessible there. For example: http://en.wikipedia.org/wiki/Human_blood_group_systems
Then, if you want to know even more, start following the references away from Wikipedia and try to get articles about the subject from medical literature.

Comment: Re:Perfect (Score 4, Informative) 171 171

Implicit question answered here. For the tl;dr & tl;dt folk: Use a vacuum cleaner.

Vor Staub braucht man keine Angst haben, denn durch den inneren Wärmepuffer kann Staub nicht bis ins innerste vordringen. Staub im äußeren Bereich lässt sich dank der Offenporigkeit leicht mit einem Staubsauger absaugen. Weil der SilentPower keinen Lüfter hat, wird Staub auch nicht wie bei normalen Computern angesaugt. Du wirst sehen, dass man ihn seltener entstauben muss als einen normalen Desktop-PC. Dennoch gilt das selbe wie bei allen PCs: Regelmäßiges Entstauben schont die Hardware.

A fail-safe circuit will destroy others. -- Klipstein

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