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July 21[edit]


Is it OK to test 220 volts AC on a single channel Oscilloscope ? (talk) 01:48, 22 July 2016 (UTC)

No it is absolutely not OK to test mains voltage on an oscilloscope, unless you know precisely what you are doing and what safety measures to take. If you need to ask here, don't do it. To answer the question, there are oscilloscopes that CAN be used on mains voltage, it should say on the scope, if you can't see a max voltage, or are uncertain how to read what is written on the scope, don't do it, seek assistance from someone with experience / qualifications. Vespine (talk) 02:05, 22 July 2016 (UTC)
(ec)Probably not. You should check the manual to see what the rating is. A knob on the front for adjusting the gain should also give a clue. Such a voltage is dangerous and could kill you, so you would need appropriate earthing and probe insulation. Instead you could put the mains AC through a step down transformer, say to 5 volts which is likely to be workable with your oscilloscope. Mains AC also has much higher voltage transients due to electric motors turning on and off, so the rating of equipment needs to be much higher to avoid damage. Graeme Bartlett (talk) 02:13, 22 July 2016 (UTC)
Live household electric wires at 220 volts can kill you. Do not work with live mains. Do not connect them to your test equipment.
For the most part, there is no good reason to hook up mains lines to an oscilloscope - that type of test equipment is normally used for analyzing much lower-power signals - it's rarely needed for analyzing power lines.
In the exceptional case where detailed analysis of high voltages or high power is required, a special probe called a current clamp is used. This allows a skilled engineer to investigate the high-power system without ever making electrical or physical contact with the mains wire. If you don't know what this is, or how to use it, call an electrician to help you. Death by electrocution is very easy when you're dealing with 220 volt mains lines. Death by electrocution happens very fast, is very unpleasant, and is generally irreversible, so don't play with wires if you have any doubts about the correct safety procedures. Nimur (talk) 03:52, 22 July 2016 (UTC)
Yes- death is usually irreversible! — Preceding unsigned comment added by (talk) 20:25, 24 July 2016 (UTC)

July 22[edit]

Audio software[edit]

I have hundreds of film songs which are named as 001, 002, 003...and so on. I want to rename them such as the song file name should be the opening lines of the song. (e.g. If the song begins with 'oh my god' then the song file name should be oh my god.) Is there any software which can do this? Thank you. (talk) 03:00, 22 July 2016 (UTC)

There is software that compares a song against a large database and changes the title to the actual title of that song. It would then need to take an extra step of looking up the lyrics and renaming it as you say. Seems possible, but I doubt if it exists yet. Something else to consider is that the opening lyrics aren't always the most memorable. StuRat (talk) 03:29, 22 July 2016 (UTC)
Further, the opening lines of songs are often used repeatedly. I immediately thought of three songs that begin with "Hit me." That doesn't get into covers of songs that will obviously use the same lyrics. So, this tool will need to have a method to handle making file names unique when the opening lines are the same. (talk) 12:50, 22 July 2016 (UTC)
True, but the actual titles are often reused, too, and they may or may not be remakes of the same song. For example, look at all the songs named "Maria". StuRat (talk) 14:08, 22 July 2016 (UTC)

SRMv2: System Restore Manager v2[edit]

1) The Disk Space to use for System Restore based on the top-right-hand-side of the software's window, the GB increments whenever I do a System Restore. Note: I don’t/didn’t install anything for quite some time now, and my Windows Update system is off.

2) Selected Fixed Drive drop-down-list of the Disk Space to use for System Restore section, is allocated in C drive. Where is this place located in the C drive, and, would it create problems if I delete files from this location?

Apostle (talk) 09:24, 22 July 2016 (UTC)

1) I suspect it is doing a backup of the backup. That is, the file it creates with the restore info is itself backed up the next time it is run. To avoid this, either the software needs to be smart enough to not do that, or you need to store the backup files some place other than the partitions being backed up. StuRat (talk) 14:13, 22 July 2016 (UTC)
I deleted the 'manual recovery point' than recreated it again, decreased a lot of GB but didn't make it zero; probably because there are two more early recovery points existing... -- Apostle (talk) 05:19, 23 July 2016 (UTC)

Crystal Oscillator[edit]

Please expand picture by clicking on it if you find numbers too small to be read

All my search on Google and at other places on the Net was only enough to ensure that the thing is a Crystal Oscillator, the numbers etc. on the top proved to be useless, was unable to find any data-sheet or even a pin-out diagram. The vendor, who (methinks) has no reason to lie, says it's a 16 MHz Crystal Oscillator (And that's ALL he knows about it). Can anyone please draw me its rough blue-print showing where and how to fit it in what type of circuit, power source be AC or DC and how much volts, what type of resistors (or other components like transistor(s) etc. ) should be fitted, and where. And how to bring its rate below 10 Mhz (if possible). Thanks (talk) 15:30, 22 July 2016 (UTC)

Actual Shape (had to make two pictures because shape and markings, which are on it's top, can't be shown in single picture)
  • Is the vendor a shady character in an ill-frequented bar? Otherwise, any info on who manufactured the chip would probably prove useful.
  • :OP is in India, and has himself received Amazon(.in) and the regional Ebay packages full of nothing but old newspaper cuttings ! This happens when Amazon etc. is in no position to dispatch and hence directs one of its contracted vendors to deliver detailed item(s) to the address they provide.
I cannot claim to understand it all, but going by this, it would seem the "crystal oscillator" is a passive two-terminal linear electrical component and the frequency comes from the eigenmode. In that case, frequency cannot be changed (except by opening the case and replacing one of the components). TigraanClick here to contact me 16:08, 22 July 2016 (UTC)
It look remarkably like an MEC crystal oscillator, 16 MHz. (talk) 16:37, 22 July 2016 (UTC)
This is MEC's website and this is their datasheet for this range of crystals. See crystal oscillator for our article on the general subject. The crystal on its own can't generate a signal, and you can't change the frequency of the crystal - you need to build a (16 MHz) oscillator using the crystal to control the frequency, and feed the output to a suitable combination of frequency dividers and multipliers to get the frequency you want. Tevildo (talk) 08:49, 23 July 2016 (UTC)
As far as the circuitry needed to make it function, that is all dependent on your ultimate goal. Crystal oscillators are simply parts of the puzzle the same as resistors, diodes, etc. What are you trying to make with that component? See here for more information. RegistryKey(RegEdit) 05:02, 24 July 2016 (UTC)
I have used a crystal oscillator most frequently to drive the clock of a micro controller. You will always find one on an Arduino board, this one happens to also be 16MHz. The processor used in a Arduino is an ATMEL AVR, and here is a tutorial about how to connect a crystal to such a processor. The only additional components you require for such a task are called load capacitors. Vespine (talk) 01:11, 27 July 2016 (UTC)

July 24[edit]

Open source and Microsoft/Apple[edit]

Have Microsoft or Apple released open source software/tools/standards? --Hofhof (talk) 13:33, 24 July 2016 (UTC)

"Open source software is at the heart of Apple platforms and developer tools, and Apple continues to contribute and release significant quantities of open source code." You can find code at: and you can read more about Unix in Apple's core system software at the System Technology Overview website.
Nimur (talk) 14:09, 24 July 2016 (UTC)
And normally, can this Apple's software be run on non-Apple computers?--Hofhof (talk) 17:12, 24 July 2016 (UTC)
Some Apple software is provided for non-Apple platforms, a well-known example being iTunes. It's up to Apple. Darwin is the free/open-source base for Apple's operating systems; since it's free software, you can do anything you want with it. However, most of the bells and whistles that distinguish Apple's operating systems like OS X are proprietary components layered on top of Darwin. Apple's licensing terms for these only allow you to run them on Apple hardware. -- (talk) 19:20, 24 July 2016 (UTC)
The last time I checked, iTunes is not open-source software. Apple certainly does not try to portray iTunes as open-source software in any way, so it seems as though the topic is drifting.
To clarify this confusion: the OP asked about open source software. This terminology is frequently confused and mis-used; and maybe our OP wasn't even sure what they were asking for. The follow-up questions seem to suggest that the OP isn't actually looking for source code, and/or does not know what one does when they have source code - in other words, it sounds like they're mis-interpreting the meaning of "open source software."
For clarity: our original questioner might be seeking:
  • software that is available at zero cost ("free software" in the sense of zero-cost); or,
  • software that can be studied, modified, and used without restriction ("free software" in the sense of liberal licensing); or,
  • source code for software (open source software, which may be either freely or restrictively licensed)
As it turns out, Apple provides instances of all of these sorts of software: some Apple software is totally non-free (restrictively licensed); some is free (zero cost) but is not open-source software, and that may or may not be restrictively licensed - an example might be some of the built-in software on your Mac; some Apple software is completely free (for example, licensed under the GPL, a BSD licsense, or similar), like the version of bash that Apple distributes; some is free and open-source under a slightly more restrictive license (including the Apple Public Source License). Apple's software falls everywhere along the entire spectrum.
It is certainly possible to build and run free, open-source software released by Apple, even on other platforms. In some cases, this requires great technical proficiency; in other cases, such as Swift for Linux, Apple provides pre-built executable programs that will run on nearly any hardware that can run a recent Ubuntu variant of Linux. Once again, Apple's software falls everywhere along the entire spectrum.
Nimur (talk) 04:45, 25 July 2016 (UTC) lists various Microsoft open-source projects. Microsoft Research has its own list, which includes the Glasgow Haskell Compiler. -- BenRG (talk) 19:12, 24 July 2016 (UTC)

Thunderbird is sending HTML code in the body of the message[edit]

Thunderbird has started sending HTML code in the body of the message. I posted a message on TB support a week ago, but haven't gotten a reply. Someone else has the same problem.

I went to Tools/Options/Send options and "send messages as plain test if possible" is checked and I changed "send the message as both plain text and HTML" to "convert the message to plain text", but that didn't fix the problem.

It doesn't do it all of the time, I don't think.

Does anyone have ideas on how to fix this? Bubba73 You talkin' to me? 16:08, 24 July 2016 (UTC)

It is doing it all of the time, unless I attach a text file. And I've tried other options for the plain/html setting. Bubba73 You talkin' to me? 16:16, 24 July 2016 (UTC)
And I have the same version of Thunderbird on an old computer, but it does not have the problem. Bubba73 You talkin' to me? 16:29, 24 July 2016 (UTC)
I would uninstall (even purge) it and install it again. --Hofhof (talk) 17:17, 24 July 2016 (UTC)
The settings do not change when reinstalling it. Settings are stored in the user profile. Send options can be modified in the settings. --Hans Haase (有问题吗) 18:16, 24 July 2016 (UTC)
That's why I said 'even purge.' Hofhof (talk) 18:48, 24 July 2016 (UTC)
What do you mean by purge - delete settings too? Maybe I should do a MozBackup from the old computer where it is working? Bubba73 You talkin' to me? 23:12, 24 July 2016 (UTC)

Neither Firebird or IE would download any file - it said "failed". I found an unwanted program called ByteFence. After I uninstalled that, downloads started working again and the problem with Thunderbird went away.

I think that Freemake Video Downloader did it. I've been using it for months - maybe over a year. The last time I downloaded an update, it installed a browser hijacker. When I searched for ByteFence, it is mentioned in the article. Bubba73 You talkin' to me? 23:22, 24 July 2016 (UTC)

What to do in Linux when nothing appears to work?[edit]

What to do when even the keyboard is unresponsive, and not even ctrl+alt+F3 would work? I've got this suggestion: Holding ALT, tap [sys rq], r, e, i, s, u, b. But this does not appear to do anything for me. Could it be that different distros need different combinations of keys? --Hofhof (talk) 17:50, 24 July 2016 (UTC)

You're going to need to provide more details. What is happening leading up to what you're describing? Are you booting the system and finding it unresponsive, or is this happening after using it for a while, or what? The SysRq thing is magic SysRq. Most distro kernels I think have it enabled, but it's not guaranteed that every distro does. Also if the system totally locks up—for instance, there's a kernel panic—magic SysRq won't do anything. It's not actually magic! Face-wink.svg It's more for, say, when X freezes. -- (talk) 19:15, 24 July 2016 (UTC)
Then again, there is always this technique...  :(   -Guy Macon (talk) 02:38, 25 July 2016 (UTC)
  • @Hofhof: Sysrq is deactivated by default, or at least restricted, on some distros. I learnt it the hard way on Ubuntu 14; see the first answer of this for how to fix it on Ubuntu (of course, once the computer froze, it is too late). What is your distribution?
Notice that there is an excellent security reason for such a restriction - but if it is your personal machine which none else has physical access to, it is not relevant. And as the IP said, sometimes, there is just nothing that will work. TigraanClick here to contact me 09:37, 25 July 2016 (UTC)
I am running Debian. I am the only user of this computer and don't fear people who could have access to my computer. Hofhof (talk) 12:24, 25 July 2016 (UTC)
If only the UI has failed, a common method for debugging is to enable the ssh server, and monitor logs from a remote machine that has used ssh to connect to the local machine, or to restart your graphical desktop environment using a shell command. If you're unfamiliar with using ssh, start with our article on SSH, and next, here's a tutorial specifically for Debian. Here is a list of system monitoring and logging tools you can use to perform basic triage. In many cases, you can simply kill and restart the graphic environment. If you're using GNOME3, here are instructions for managing gdm on debian, including the "correct" way to stop and restart its UI services.
When things go really wrong, like a kernel panic, it means the bug is much more severe, and the system has crashed beyond just the graphical interface. In those cases, you need a lot more expertise: you'll have to set up the machine for kernel debugging, and you'll need a second machine; and sometimes you will require specific computer hardware that makes such debugging possible. If you aren't familiar with this type of workflow, your best recourse as a user is to check if the release notes describe any known bugs and solutions.
Nimur (talk) 14:12, 25 July 2016 (UTC)
  • "Debian" (whatever version that is) is a lot like Ubuntu (purists will say it is rather the other way around); going by this forum thread, in particular post #3, the spirit of the Ubuntu thread I linked likely applies. Check if your "magic key" variable is set to accept the "REISUB" sequence.
Additional note: you have to hold down both alt and sysrq while typing in the sequence. On some keyboards configurations it is even Fn+Alt+Sysrq held down during the sequence (so 4 keys at a given time). TigraanClick here to contact me 15:54, 25 July 2016 (UTC)

If the "keyboard is unresponsive" wouldn't the first thing to try is another keyboard? CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 01:00, 26 July 2016 (UTC)

Forgive the user for a little bit of imprecise language in describing the symptom: it's a near-certainty that the keyboard hardware is not a causal factor in this case. The user meant to say something to the effect that the computer system fails to respond to keypress events. This is most probably due to a software bug in the desktop environment management software, or to a kernel oops, which (for most end-users) would be caused by an undiagnosed software bug in some device driver. There is a near-infinite list of other possible causes, and strictly speaking, we can't rule them out until we disprove every possibility, but in a typical workflow diagnosing such a problem, the first action is to start the investigation by collecting detailed information about the symptoms, and chasing down the most probable causes. Nimur (talk) 17:48, 26 July 2016 (UTC)
Has the keyboard ever worked with this OS installed or is this a new OS install? Is this by any chance a Debian install on the Raspberry Pi? Akld guy (talk) 20:34, 26 July 2016 (UTC)

Why is everywhere so desperate for you to use their app instead of their site?[edit]

i.e. Pinterest but especially obscure sites that are commodities (i.e. a funny picture site) and couldn't be helped by an app (unlike i.e. Google Maps). They probably had to pay someone to write that stupid app for them. Why? If you actually got all the apps pushed in your face the phone would be clogged with apps that were only used once. Do the apps have a $.99 to $3.99 or so purchase or something that's far, far, far more valuable than advertising income? Do app ads pay more than site ads? Is it like this?: Say app and suddenly everyone wants it Sagittarian Milky Way (talk) 19:39, 24 July 2016 (UTC)

One reason is that apps can get access to personal information, such as a unique phone ID and your contacts, that in-browser Javascript is typically blocked from accessing. -- BenRG (talk) 01:44, 25 July 2016 (UTC)
Another reason is that they can be more in your field of view, doing alerts and popups, so even if you don't visit their web site or fire up their app they can get a message on your phone screen. Graeme Bartlett (talk) 06:34, 25 July 2016 (UTC)
While apps may be able to do a bit more, websites can now send notifications via the browser if it supports them and the user allows it. Most major browsers on mobile platforms do, with the notable exception of Safari on iOS [1]. (If you've ever agreed to let Facebook send notifications via the browser, you'll probably see it isn't that different from the app.) Nil Einne (talk) 11:43, 25 July 2016 (UTC)
I have some experience with this regarding restaurants. They give their apps away for free, often with an incentive, like a free app (appetizer) when you get their free app (application). I can think of two reasons they hope to eventually implement:
1) GPS related offers. So, when they see you are on "restaurant row", but just walked past their restaurant, they may send you an offer to get you to turn around and come in.
2) Inventory related offers. When they see they aren't going to sell all their shrimp before they close, they might search for anyone in the area and offer them a discount on shrimp to get rid of the excess, before they close and have to toss it out. Or they might send the offer out to everyone, but those who get notifications on their cell phones will presumably see them sooner than those who may not view their email until the next morning, and, once home, people are more reluctant to go out again.
Now these ideas might not be implemented yet, but meanwhile they want to increase their user base so it will be there when they are ready. StuRat (talk) 15:10, 25 July 2016 (UTC)
  • Previous answers boil down to "collect user data for profiling future advertisement", which is likely true, but I see another reason here in the case of apps that include advertisements.
At least 99% of web advertisement today, either in terms of money or data, is delegated by websites to third parties (Google, Criteo, etc.). In-app advertisement is probably not much harder to block than in-browser, technically (I think? putting Google et. al.'s advertising domains on the IP blacklist) - but few know how to fiddle with hosts (file), while a significant proportion of internet users can hit the "download Adblock plus plugin" button on their browser. Attack ad: ABP runs an extorsion racket - use Ghostery instead. As a result, the proportion of users that will use your service but not generate ad revenues will be much lower with an app.
Slight off-topic: Note that this delegation to third parties makes it (relatively) easy to filter out the ad traffic, but before ad blockers the delegation was a win-win. Website admins do not have the technical headache to set up the advertisements as it is taken care by specialists; they do not need to vet advertisers, make them compete for spots, etc. On the other side, big ad companies can collect user data across multiple sites, use big data voodoo to profile the users, and serve them tailored advertisements. This increases by a large factor the click-per-view and buy-per-view statistics, which means an advertiser will be ready to pay a lot more per view. TigraanClick here to contact me 16:16, 25 July 2016 (UTC)

July 25[edit]

Microsoft after 2025[edit]

Starting a year ago, everything is Windows 10; there never will be any newer version of Windows. However, as early as late 2025, Windows 10 will become obsolete, according to the article Windows 10. What Microsoft software will be available for 2026?? This question's answer should be known by this time next year. Georgia guy (talk) 21:55, 25 July 2016 (UTC)

Those dates apply only to "Windows 10, released in July 2015", i.e., if you never install newer versions like the upcoming Anniversary Update. I edited the article to make that clearer. -- BenRG (talk) 05:37, 26 July 2016 (UTC)
If the answer will be known next year, how could we know it now? 2606:A000:4C0C:E200:807B:66FA:B5EC:A602 (talk) 01:55, 26 July 2016 (UTC)
What is the statement that "there never will be any newer version of Windows" based on ? If we accept that as true, there are at least 2 ways to interpret it:
1) They will just call new versions Windows 10.x, like they did with Windows 3.x for quite a while.
2) Microsoft may plan on leaving the PC operating system market entirely, considering mobile devices to be the future. They may have different names in mind for the O/S's on those. StuRat (talk) 02:06, 26 July 2016 (UTC)
Or 3) they will stop using the discrete version model of releasing software in favor of the software as a service model See [ ] For those using it, quick, without checking, what version of the Google chrome web browser are you running? --Guy Macon (talk) 06:38, 26 July 2016 (UTC)

July 27[edit]

Some C# help needed[edit]

Hi guys! Could somebody help out with C#? If I have regex pattern ([^\.])<ref>.*?<\/ref> (Lorem|Foo)? bar and string "Foo<ref>Foo</ref> Foo bar", how to change to lowercase only the second match (in this case - the "Foo", that comes after ref)? If I would need to lowercase everything, I would use something like (tested with other string, so this one may contain some small bugs, but you got the idea):

	string text = @"Foo<ref>Foo</ref> Foo bar";
	string pattern = @"([^\.])<ref>.*?<\/ref> (Lorem|Foo)? bar";
	text = Regex.Replace(text, pattern, delegate(Match match)
	    string v = match.ToString();
	    return v.ToLower();

Note, that this is for AWB module, so it might not look very C#-ish. --Edgars2007 (talk/contribs) 09:16, 27 July 2016 (UTC)