Cutting the ground wire in an isolation transformer?

Question: I bought a non-tech isolation transformer (500w), which I planned to cut the earth mains ground from the output, but leave the chassis grounded; however, when I opened it up I found the output outlets were grounded to the chassis and the chassis connected to the mains ground. So I just cut the ground. Now my isolation transformer is floating both on the primary and secondary coils. Naturally this means the outer case is no longer grounded and if there was a short within the transformer, touching the case would be bad. Otherwise, does anyone see if this will lead to a dangerous scenario when I am probing the DUT with a grounded oscilloscope? Assume that I plan to connect the black alligator clip of the oscilloscope to any arbitrary point in the DUT.
Comment: Thanks for the excellent responses. As to the keeping the chassis grounded, I didn't see a way to do that since the output outlets are mounted with metal screws to metal brackets to the chassis and this connects to the ground plug. I thought about trying to insulate it with rubber gaskets and such but I wasn't sure that a small breach could be prevented and what would be insulated today might develop a continuity later with disastrous consequences.
Answer: I think what you did was close, but I wouldn't leave the whole chassis floating.  I'm assuming this isolation transformer comes with a standard 3 prong outlet for the output side.  Just disconnect the ground connection on this outlet, but continue to let the input side ground be connected to the chassis.
Generally you want as little as possible floating at some arbitrary voltage.  There will be plenty of other things around at the normal ground potential, so the chassis of the transformer isn't going to make anything worse.
I agree with Dave in that I don't understand why isolation transformers come with the grounds connected.  I got one that way too many years ago, but didn't expect it.  I actually blew out a fuse before realizing that the grounds were connected together inside the box.  I don't know what they think isolation means, but different from what I had assumed.
By the way, beware of inrush currents on a 500 W isolation transformer.  All the ones I've seen are toroidal cores.  These can retain residual magnetism depending on what part of the power cycle they were turned off at.  If this happened to be at one peak and you turn it on next time near the other peak, there will be a very large inrush.  I once blew a 30 A breaker with such a transformer, even though I had switched it on a number of times previously on the same circuit.  Unfortunately this was on a weekend and the breaker was in a different locked room.  Argh.  Often you want to adjust the voltage anyway when you're debugging power circuits where you want isolation.  In that case, put the variac before the isolation transformer instead of after it.  If you bring the variac voltage up and down with the knob, there won't be much inrush.
Answer: You've actually done the Right Thing, although you need to be aware that the case of the transformer is now going to be at the same potential as the DUT ground, so any faults in the DUT (not just in the transformer itself) could cause problems. The better alternative is to use a 3-wire to 2-wire "ground breaker" adapter between the transformer and the DUT.
This is a bit of a pet peeve of mine. The whole point of an isolation transformer is to get a source of AC power that is completely isolated from (floating with respect to) the mains ground. Connecting the ground from one side of the transformer to the other completely negates this, and I don't know why they do it. The only reason you're using the transformer in the first place is because the DUT's ground is not already properly isolated from the line/neutral input!
At most, there should be a high-value resistor (e.g., 1MΩ) in parallel with a smallish capacitor (e.g., 1nF or less) connecting the two grounds. The resistor drains off static charges, and the capacitor provides a certain amount of RF bypass.
Answer: Now your scope ground can be on any potential (possibly deadly). It is always safer to use differential voltage probes. Take a look at this Tektronix technical brief.
Comment: Really, *always*!?  You are assuming a narrow usage for isolation.  Some don't even have anything to do with a scope, and differential probes have their own issues.  Sometimes they are a good answer, but it's absurd to say you should *never* float a circuit to test.  And yes, sometimes that will include floating the scope too, in which case you need to be extra careful, but to say this should *never* be done is overreacting.
Comment: You're thinking about the situation when the scope is plugged into the isolation transformer. I'm pretty sure that @John is plugging the DUT into the transformer.
Answer: Yes, I know it's an old question, but there is a potentially fatal issue which has not been addressed and it is entirely to do with what the isolation transformer may be used for after you've finished doing what you need with a scope and a DUT.
This answer is for the part of the question which reads: "...does anyone see if this will lead to a dangerous scenario..."
For safety, all earth connections on the output sockets of an isolating transformer must be linked together, but must not be connected to the input earth of the isolating transformer.
Two operators could be using using equipment plugged into different output sockets of an isolating tranformer.  Assume both operators are using metal-cased tools and the case of each tool is properly earthed to the earth pin on the flexible cord of the tool.
Scenario one of two: the output earths in the isolating transformer are not linked together: One operator has an unsuspected short circuit from phase to earth in his tool.  The other has a short circuit from neutral to earth.  Either operator may use his tool in perfect safety with this isolating transformer - right up until one operator touches the other and they both are electrocuted.
Scenario two of two: The output earths in the transformer are connected together: In the case of two faulty tools as described above, the operators are immediately alerted and kept safe because as soon as the second tool is plugged into the transormer, it blows the transformer secondary fuses.  And as there can be only one reason for that occurrence given that both tools are known to be operating well individually, it will be instantly known that both tools need urgent repair.
A rare scenario, yes, but one which almost guarantees a fatal result when an isolating transformer is borrowed by a couple of tradespeople who are going to work in close proximity to each other.
So it is critically important to link all output earths in isolation transformers.  If a problem arises when using an oscilloscope and DUT on a workbench, then do anything else to alleviate the problem but do not unlink the output earths in the transformer.  Other people need to have implicit trust in the transformer when they use it.


Schengen visa in US without H1B stamp

Question: I was on F1(OPT) visa in USA. My H1B got approved couple of months back and I will be going to India for stamping H1B visa. I am planning to stop in Switzerland for a week for vacation while going to India.
Can I get the Schengen visa here in SF as I don't have H1 stamped?
I do have H1B approval notice. After staying in Switzerland, I will be going to India for stamping and then coming back to USA on H1B visa.
Comment: Have you changed your status already?  If not, then you are in the US in F-1 status, and your F-1 visa will serve as evidence of your legal residence in the US.  As noted in Henning Makholm's answer, the Swiss consulate should be aware that it isn't necessary for the visa to remain valid during your stay in the US.
Comment: My status is already changed to H1B from F1.
Comment: In that case your change-of-status approval notice, valid I-94 reflecting H-1B status and approved petition are proof of your legal residence in the US.
Answer: It should not be a problem.
The relevant condition for applying for a Schengen visa is just that you're legally resident in the coverage area for the consulate you're applying to. It is perfectly possible to be legally resident in the USA without having a current visa, and consulates in the USA know this well.
Another possible problem is that the consulate want to be sure you can actually leave the Schengen area when you say you will. That could have been a problem if your plan was to return to the US directly, since you don't have a visa that would allow you to board a plane.
But in your case your plan is to go to India when you leave the Schengen area, and presumably you already have all the paperwork you need for that (namely, a valid Indian passport), so there's no doubt that you will be able to do so.
If problems with getting your new US visa develop, it will be after you've left the Schengen area, so that's not a risk the Schengen consulate would care about.
You will still need to show that you have plans for your future that would seem more attractive than "stay in Europe as an illegal immigrant", but simply documenting a well-reasoned expectation that you will get an US visa when you reach India ought to take care of that.
Comment: It sounds like OP is still in F-1 status, so he or she may even have a valid visa (namely the F-1 visa). Also I found [this document](https://www.eda.admin.ch/dam/countries/countries-content/united-states-of-america/en/131.30_Merkblatt_Visa_for_tourism.pdf), which lists "Notarized copy of proof of residency in the USA, e.g. a valid permanent resident card (green card), H1B visa (plus I-797), F-1 visa (plus I-20), etc."  Presumably a valid I-94 record would be helpful, too.
Answer: So I was in a similar situation. I have been invited by a University in Venice to attend a workshop in June 2019. I am planning to travel to Italy with my family.
I used to be on an F1 student visa, but since graduation, I have transitioned into H1B now with current I797 Notice of action (valid until 2022) in hand. My wife and I don't have our passports stamped as we did not travel outside of the United States since 2016 (last time I entered as an F1 and my wife on F2 visa status).
I had an appointment last week at the Miami Italian consulate. They were asking for a valid visa stamp on the passport which I don't have as we have not traveled to my home country (India) and we intend to get the updated visa stamping done after my workshop in Italy.
Fast-forward three days >> So here is our experience at the Consolato Generale d'Italia in Miami. We went there with my wife and 1-year old child. We reached Miami 7:30 in the morning and went from there to the consulate. Our experience has been only positive. The staffs were highly accommodating given we were traveling with an infant. They asked us only the simple questions, and when asked about producing the long term visa document, I gave them my I797A Notice of Action, and they accepted it readily. Finally, we were ten-printed, and that's all. I am waiting for my Schengen visa in mail.
I hope my experience brings some hope to others who are in the same boat.
Comment: Here's a link to [your question and answer](https://travel.stackexchange.com/q/137713/19400) for those who might want to read it.  I would note that one of the frustrating things about the Schengen system is that different countries interpret and apply rules differently, so your experience at the Italian consulate is reason for hope with a Swiss visa application, but there is still reason for worry that they might apply the rules slightly differently.

Schengen visa in US without H1B stamp


Are champion and skin sales on a fixed rotation?

Question: I only buy champions and skins when they go on sale. Is there a way to know what will go on sale ahead of time, or is it completely random?
Answer: No, they usually do a poll and ask the community what skins they would like to see on sale to benefit them and to profit and pocket the most money. A brilliant strategy, in my opinion.
As for champions, anytime they release a new champ, it will be free 2 weeks later in that rotation. That's the only thing that's set in stone with the champion rotation, otherwise they balance out bruisers, AP and AD carries, jungle and supports.
Comment: Can you provide a link to the poll?
Answer: I usually find that skins are on sale within a month of releasing or on the holidays. New champions usually become free 2 weeks after they come out. This doesn't always happen but I'm just trying to help. =D
Answer: No, they generally put things on sale that aren't selling too well so they get the money.


Who was the Holy Roman Emperor that was a travelling adventurer?

Question: I recall reading about a medieval Holy Roman Emperor, or heir apparent, that didn't get to rule over the kingdom. He was the last in line from a major dynasty, and held a high amount of prestige. He travelled around, undertaking various adventures and battles, especially in the east. He was a popular figure because of his exploits. Whatever the condition of Germany was at the time, he didn't get to have a typical rule. I think it was in the 15th century, possibly during the Hussite Crusades. It sounds obscure but he was actually the emperor, or was quite legendary.
Answer: I looked at Wikipedia's list of emperors to no avail. I realized he may have been a king of Bohemia, so I went back and looked at that. It was John the Blind, son of Henry VII, Holy Roman Emperor. The Luxemburgs lost the crown to the Louis IV Wittelsbach. Henry therefore was only king of Bohemia and Poland, but never emperor. I was going to sack my question, but I highly recommend reading about this fellow.
John of Bohemia (Wikipedia)
Comment: Don't "sack" your question unless it gets down-voted to oblivion - this answer might be valuable for someone else in future.
Comment: @John Dee - King John of Bohemia was not only the son of Emperor Henry VII (not to be confused with the other imperial Henry VII) but also the father of Emperor Charles IV and grandfather of King of the Romans Wencelaus and of Emperor Sigismund.  So it would be easy for you to misremember him as an emperor.
Answer: You may be referring to Don Juan of Austria. He never became Holy Roman Emperor because he was the illegitimate son of Emperor Charles V, in the sixteenth century.
But "son" of the Emperor helped get him into high military positions, where his abilities allowed him to have many adventures, and to make a name for himself, notably at the (naval) Battle of Lepanto against the Turks.
Comment: Comparable scenario, but not medieval enough.


What do the good/evil sliders do in DeathSpank?

Question: DeathSpank's settings have Good/Evil sliders.
Does tweaking them change anything? Are they just a joke?
Answer: Move good all the way to the right, and evil all the way to the left to get the "Menu Hero" trophy. Other than that, they are just a joke.
Answer: If you slide the "Good" slider all the way up and the "Evil" slider all the way down, you will unlock the "Menu Hero" achievement / trophy.  Beyond that, I haven't noticed any effect on the game.
I strongly suspect these sliders are simply meant make players go "Huh?" :)
Answer: When I slid them around,I noticed the UI and the color of everything that wasnt the game itself change,for example,the menu,if slid all the way to Evil,was all red and the sky was a darker color. If slid all the way to Good,it becomes day and bluish.
Answer: They are apparently an in-joke of sorts. probably poking fun at all the morality things in games or something my philosophical. I mean how does one judge good and evil? :p
as far as gameplay goes, they're there simply to give you an achievement.


Map generation when it is already in JPEG format

Question: I got maps in JPEG format but I need some information to be added in it. I can't start editing in JPEG format. If there is any other procedure to add other features into it. Then please let me know.
Comment: I think you can use the map as background raster image (probably will need georeferencing) and then you can add new layers and later create new layout. But of course, you will not be able to remove or modify existing data in the jpg map.
Answer: I often get maps in an image format (usually a poorly aligned scan of a photocopy of a creased map that somebody drew on with crayons).
You have three options.  The first is to follow Juhele's advice to georefernece your map and use it as a raster backdrop to your new features.  The other option is to use GIMP or Photoshop if you want to do something simple like edit typos in the legend or add a couple of place-markers or a call-out balloon to describe a feature.
You're pretty much stuck with the layers that are already in the map you've been given, but if you MUST remove something, remember that it's just a raster and Arc has a whole slew of tools as do GIMP and Photoshop that will allow you to selectively change the appearance of a raster.  Just remember that everything is editable, but not all edits are advisable :)
The third option is to ask for the MXD file (assuming the person who provided you with the map uses Arc) and/or the raw data.  Then you can do what you like with it.


No LAN and SMB access, and Explorer not responsive, when using a second connection

Question: I apologize if this is a duplicate question, I know that there are several questions about multiple connection (LAN + LAN and LAN + dialup) but I haven't been able to find one that fits my scenario.
I'm still using Windows XP on my corporate laptop, and I'm connected to the corporate LAN via Ethernet. The LAN NIC has a public IP address, although not accessible externally, obtained via the corporate DNS server. This connection is firewalled and requires a proxy to access Internet.
To access Internet sites blocked by the corporate firewall, I use my smartphone via USB tethering. It is seen as a new LAN interface, and I get a private IP address (class 192.168..).
There are two problems:

The LAN is not accessible, as the default gateway goes to the tethering NIC. I'd like to solve this, but I can live with it.
My PC becomes unresponsive if I use Windows Explorer to view local files, or even when I open the start menu. I guess that this is caused by attemps to connect to a mapped network drive. But I disabled the "Client for Microsoft Networks" in the tethering NIC. Why the system still hangs? Of course if I disable the Ethernet NIC, Explorer stops hanging.

If you need further details, add a comment. Thanks!
Answer: I wonder if manually adding routes for your corporate network on your machine would help? Let it keep your tethered connection as the default, but then add routes to your table for your corporate LAN. So if your corporate subnet is 10.12.10.x 255.255.255.0, type this in your command prompt:
route add 10.12.10.0 255.255.255.0
Make sense?
Comment: Of course this entry is already in the routing table...


How to add rotation to two particle collisions?

Question: I'm trying to make a particle system where when particles collide, they merge together, to get the new velocity vector the smaller particle's force is added to the larger one. However, this isn't exactly how I want it to work because when a small particle hits the edge of a large particle it shouldn't simply move in the direction it was hit. It should impart a rotational force, and that should be resisted by inertia. The further away from the center the more it should rotate the particle as opposed to pushing it. What is the physically accurate way to approach this problem?
Comment: Possible duplicate of [Calculating collision of polygons](https://gamedev.stackexchange.com/questions/150238/calculating-collision-of-polygons)
Answer: If a billiard ball (pool, snooker, whathaveyou) hits another 50% from full on, I am pretty sure there is no creation of angular momentum.
If the first ball had no rotation, I don't think the 2nd ball would be rotating after being struck.
That said, if you did want to introduce it on collision, just take the cross product between vector A and B, where:
A is the velocity vector of ball 0.
B is the unit vector pointing from ball 0 to ball 1.
Then use the magnitude of the cross product as a measure on how much side-ways the impact was. Use the sign to determine which direction to spin the particle, L or R.
If you work in 3D, just use the entire cross product vector for rotation direction and magnitude.
If both balls are moving, you should probably do the same again with roles reversed.
I think more physically correct would be not to add angular impulse based on grazing factor. Instead, transfer existing momentum, regardless on how much full-on the contact was.But I think that requires taking elasticity into account.
Comment: Not really correct; the amount of rotation created depends on elasticity of the impact, and friction between the object. Billiard balls have very high elasticity (they are still round after the impact), and relatively low friction, so  for your example, there is little rotation. However, if you would cover them in pelt or rubber (for friction), or make them from dough, the behavior would be quite different!
Answer: I am not able to write down the exact formulas from the top of my head, but some starting points:

you need to define the friction coefficients between the two objects. Friction is a function of both object's surfaces, but you can simplify to giving each surface a coefficient, and always use the larger one when two objects connect.
you need to define each object's elasticity, between 0 and 1. A billiard ball would be very near to one, and for example foam would be about zero. Again, you can simplify, this time to always use the smaller value.
when the objects touch, the total momentum is always kept (mass1 * velocity1 + mass2 * velocity2 = const, where velocities are vectors)
also, the total energy is always kept, but a part of it is converted to deformation energy = warmth (mass1 * velocity1^2 + mass2 * velocity2^2 = const)
your elasticity defines how much energy gets converted into deformation
your friction coefficient defines how much energy gets converted into rotation
the rest goes into v1 and v2 after the bounce
from the two equations, you can calculate the momentum and rotation of each object after the touch: (1) total momentum before = total momentum after touch = const; (2) total move energy before, minus deformation, minus rotation = total move energy after the touch.
from the amount of energy going into rotation, and the data about the object's rotational inertia, you can calculate the rotation speed of each object

That is all not that trivial, but such is the real world.
Answer: The correct physics to use here is conservation of angular momentum.
For the two particle collision you describe, it will be easiest to calculate the angular momentum about the center of the large particle.  Then the initial angular momentum will be L=mvr, where m and v are the small particle's mass and velocity, and r is the perpendicular distance from the small particles trajectory to the center of mass of the large particle.  The final angular momentum will be L=Iw, where I is the moment of inertial of the large particle, and w is it's angular velocity.
Solving these gives,
mvr = Iw
w = mvr/I

If the large particle is a sphere, then it's moment of inertia will be I = (2/5)MR^2.  So,
w = (5/2)(mvr/MR^2)

I suggest reading a bit about angular momentum, if this doesn't call the topic to mind.
Note also that this matches part of your intuition, that the "further away from the center the more it should rotate the particle as opposed to pushing it".  This is the r parameter, so the larger r is, the more it rotates (ie, w is larger).  But the other part of this intuition is incorrect: it doesn't rotate more "as opposed to pushing it".  It is pushed the same amount, that is, the center of mass about which this combined particle will spin will move at the same speed in both cases, since this is due to conservation of linear momentum which is independent of r.  This incorrect intuition probably comes from the idea of conservation of energy (that if more energy goes into spinning of the particle than it's going to have to move slower), but that's not useful or correct in an inelastic collision (such as here when the particles stick together).

Below are answers to possible questions:
Are linear momentum and angular momentum independent?:
Yes, linear and angular momentum are independent in the sense that both quantities are always independently conserved within a closed system (ie, one that has no external forces or torques applied to it).  They are different in some ways, for example, linear momentum is a fundamental property of all masses whereas angular momentum is a derived quantity that's primarily useful only for rigid bodies.
What's the difference between momentum and force?:
Momentum is a property of a body, force is a thing that's externally applied to a body that changes its momentum.  Similarly for angular momentum: Angular momentum is a property of a body, torque is a thing that's externally applied to a body that changes the angular momentum.  So when the question mentions, "get the new velocity vector the smaller particle's force is added to the larger one".  This statement is true if the word "momentum" replaces "force", but without that substitution it doesn't really work from a physics perspective.  And in this case, the correct momentum is linear momentum (p=mv), not angular momentum.
When are conservation of linear and angular momentum useful: In these rules, it's important to keep in mind that the conservation rules only apply to closed systems, that is, systems without external forces and torques.  To understand this, consider two variations on a somewhat similar example: 1) If a spinning wheel is dropped onto the ground, then the ground will apply an external force to the edge of the wheel (so it's both an external force, and a torque about the axil) and this force and torque will both reduce the spin of the wheel (the external torque will reduce the angular momentum) and make it move forward (the force will increase the linear momentum).  That is, neither the linear or angular momentum are conserved because both an external force and torque have been applied.  But, 2) if two spinning wheels collide in space (so it's a closed system with only two interacting bodies), then the collision will preserve both the total linear momentum and the total angular momentum.
How about elastic vs inelastic collisions: Unlike conservation of energy which only holds for elastic collisions, conservation of linear and angular momentum holds for both elastic and inelastic collisions.
Comment: Incredibly well explained, The linear vs rotational momentum seems a bit counter intuitive,  I did not expect them to be totally independent forces. So I guess I can add them separately.
Comment: Great. Glad it was helpful.  I'll answer your question in my main answer so I can have sufficient space.


Why become a Registered eFiler?

Question: I would like to submit a provisional patent via EFS to the USPTO.  There is an option to submit as a registered eFiler.  What reason would I want to perform the submission as a registered eFiler?   If I submit the PPA unregistered, can I register later and have the PPA attached to the registration as if I had submitted as registered?
Answer: Yes, you can attach it latter as long as you know the application number and filing date. If you lost that information you might have some hoops to go through to show that it was you that filed.
Comment: Great info.  I'm finding USPTO customer service to be excellent for solo-inventors.  The provisional process, at least, seems to be functioning as intended for the little guy.

Why become a Registered eFiler?


What is the SQLCLR wait type in Activity Monitor within SQL Server Management Studio (SSMS)?

Question: When I check our SQL Prod server, every time I open Activity Monitor I always see SQLCLR on the first list on the resource wait section in the Activity Monitor. It always has a high number. What is SQLCLR for? Is it bad for the server having that SQLCLR with high resource wait number in the activity monitor?
Answer: SQLCLR is the ability to run .NET code within SQL Server.
When people speak of SQLCLR they are usually referring to the ability to write custom .NET code (Stored Procedures, Functions, Triggers, User-Defined Types, and User-Defined Aggregates). In this case, this ability can be turned on and off via the server option of "clr enabled" within sp_configure, and I believe it's called "CLR Integration" in the Surface Area Configuration GUI. Adding .NET functionality requires using CREATE ASSEMBLY to load the compiled .NET code into SQL Server.
However, even with the "clr enabled" option set to 0 / "off" / "disabled", CLR functionality is still used for internal functionality and some built-in functions and will always be there, unless the "use Windows fibers" / "lightweight pooling" option is enabled.
For a very detailed description of what SQLCLR is, is not, and what it can do, please see the article that I wrote on this topic on SQL Server Central: Stairway to SQLCLR Level 1: What is SQLCLR? (free registration is required to view content on that site). A stripped-down version of that article is available in the following StackOverflow answer: When do we need a CLR function in SQL Server?.
If you want to know whether or not the instance is allowing custom .NET code to be added to databases, run the following and check the "run_value" field:
EXEC sp_configure 'clr enabled';

With regards to the meaning of the SQLCLR wait type in Resource Monitor, please see the following blog post:
How It Works: What is behind the SQLCLR wait category in SQL Server 2008 Activity Monitor
and I believe the pertinent line (as it pertains to the SQLCLR category you are looking at) from that post is:

What I found was that several of the wait_types should be ignored as they are expected waits.
Comment: `SELECT * FROM sys.dm_os_wait_stats WHERE wait_type IN ('CLR_AUTO_EVENT', 'CLR_CRST', 'CLR_JOIN', 'CLR_MANUAL_EVENT',
'CLR_MEMORY_SPY', 'CLR_MONITOR', 'CLR_RWLOCK_READER', 'CLR_RWLOCK_WRITER', 'CLR_SEMAPHORE', 'CLR_TASK_START',
'CLRHOST_STATE_ACCESS', 'ASSEMBLY_LOAD', 'FS_GARBAGE_COLLECTOR_SHUTDOWN', 'SQLCLR_APPDOMAIN', 'SQLCLR_ASSEMBLY',
'SQLCLR_DEADLOCK_DETECTION', 'SQLCLR_QUANTUM_PUNISHMENT')
ORDER BY wait_time_ms DESC, wait_type ASC;`
Comment: That's SQL2008, and was supposedly scheduled to be corrected (based on the linked article).  The OP has flagged SQL 2012.  I'm just looking at the same thing as for me SQLCLR is sitting steady at 3000ms +-1 and we're not using it.
Comment: @RogerWillcocks Scheduled to be fixed does not always mean that it will be fixed. If you read through the comments on that linked post, you will see people reporting that it is still an issue in 2012 SP1 and SP2. What version of SSMS are you using? Run the following (next comment) to see if it matches what you are seeing. Also, there are several built-in features that do use SQLCLR, such as the Geometry, Geography, and HierarchyID types; the FORMAT command, and some other stuff.


Geoprocessing Tools on ArcGIS 10.2 and Visual Studio 2012 -issues

Question: I am migrating one of the existing project (custom Geo-processing tool- class library project) source code which runs on ArcGIS 10 SP4 and Visual studio 2010. This is working fine. I am could run the project and able to add this tool in ArcTool box. Publish this as GP service and consumed in application.
I am moving this code to new machine which Windows 2012 server and  ArcGIS 10.2 and Visual studio 2012. The source code is fetched from TFS and and code is built successfully after updating ArcGIS libraries to 10.2 When I run the project in VS2012 - class library (starting - ArcMap.exe with specific mxd document  as input) break points are not hit.
After doing some research I have found that ESRI Link here I have to update ArcMap.exe.config file. After updating config file to use Framework 4.0 break points are set but not getting hit. Whenever I run the class library project MXD is opens, but the break points are not getting hit and not able to debug the code. Project properties in VS2012 is same as I used in VS2010 (checked Register COM Exception) and enabled debugging.
Question:
a) Why VS2012 is not hitting breaking points?
b) Dll is successfully built, but I am not seeing this custom tool box in "Add tool " box in ArcTool box.
I am not sure what am missing or some changes in ArcGIS 10.2. Please help.
Answer: Why VS2012 is not hitting break points ?
a) I ran ArcGIS code Migration Analyzer from Tools Menu in Visual studio 2012. This pointed list of issues like some dll like ESRI.ArcGIS.Geoprocessing specific version set to false.
b) Project build property set to "Any CPU"
Why tool is not added to tool box
a)Need to explicitly register the dll by right click and select "Desktop".
Hope this helps.


Copy/Migrate FileVault 2 encrypted hard drive

Question: I'm running OS X Mavericks and have the entire hard drive encrypted with FileVault 2. I intend to upgrade to a larger hard drive (actually an SSD). In the past when not using FileVault, I used Carbon Copy Cloner to copy the entire disk to the new hard drive. Can this be accomplished with a FileVault protected drive?
Answer: SSD is different, it needs a separate driver from OS to work properly. It is better that you archive your drive using time machine, install OS X as usual and than, during the last install step, restore your home directory. This will ensure that your system uses all correct drivers and your SSD will live a healthier life.
When archiving with time machine, you can drag /System into the exclusion list to avoid archiving OS X itself (you'll be reinstalling it).


How does Demon: the Descent handle the common problems with Splinters and Time Travel?

Question: So the main Demon the Descent features a campaign seed based on time travel but it doesn't discuss the "common" time travel issues such as causing a paradox, meeting yourself in the past, or reasons why the god-machine would form splinter timelines beyond storyteller fiat. Is this simplified time travel meant to be part of the setting or am i missing a reference somewhere in the book?
Answer: You seem to be talking about splinters mostly:

Splinters are not timetravel as such

They are parallel sub-universes that are not time matched
Think of it more as a teleport to a parallel dimension
at no point do you move through time at anything other than 1 second per second, like everyone else.
Most have some kind of period reset,

where it goes back to the start of its time loop
People except stygamtics and demons loose all memory of the last loop
there are other cool mechanics relating to this

Most are localised to a small area, much smaller than a city

You phyiscally can't leave the area

There was a exception to both rules in dtd core.

A time period that was several hundred years back, but that had continued progressing. and which had sailors arriving in port.

Again, splitters are not really time travel,

because by entering one, you go to a fixed point in time, in a parallel universe,
so changes made in a splitter don't effect the main timeline

IIRC some of the results from destroying a splinter, do result in the changes being merged into the main timeline.
Some exploits etc are also time-travel like, Eg 4 Minutes ago from DtD core p 166.

these abilities tend to be quiet explicit about what they do.

There is also true timetravel via infastructure as a story hook in the God Machine Chronicle

Paradoxs Etc

Sidebar Page 237 DtD core: (Emphasis, Mine)
TIME TRAVEL
  One type of story we haven't shown much in the  World of
  Darkness bears special mention — whether through Infrastructure, the
  powers of arch-angels, or sheer cosmic strangeness such as the
  splinter Seattles (see the Appendix), characters in  a Demon chronicle
  can find themselves travelling  in time.
Time travel in a horror game
  fits as a subset of  Universal Machinery, above, showcasing a story
  where the slightest wrong move can have terrible  unforeseen
  consequences. Time in the World of  Darkness isn't elastic and doesn't
  bounce back  from alteration like it does in many science fiction
  stories, nor are temporally-displaced demons prevented from causing
  catastrophic changes through  paradoxes. They are also not aware of
  the rules of  what they can and can't change. If the characters  alter
  history, treat it as any other cosmic change —  show the damage and
  reveal the long-term fallout.  If the characters are careful in the
  past, make  changes in subtle ways — a street name here, the  details
  of a Storyteller character there. Look to  films like The Butterfly
  Effect or Source Code, or  stories like "A Sound of Thunder" or The
  Anubis  Gates for inspiration.

To me however that is less of a solution, than just repeating the question.
Basically the rules explicitly don't handle paradoxes or altering the past,
or meeting yourself.
Thus what I get out of it, is storytellers are up to there own devices when it comes to handling Timey-Whimy things.
I expect we will get some more guidance when the Storytellers guide comes out.
(If it is a full of guidance as Flowers of Hell was for players)
Why would the God Machine create splinters?

By accident of Facilities:

Time and Space are the same thing, kinda, right?
Infrastructure warps space, this is why facilities are often bigger on the inside (I can't find my citation for this any more)
when that warping becomes intense, it also may warp time right?
When the warping becomes too intense, the fabric of space-time itself might tear off, leaving a section hanging only by a thread. That section is the splinter. If anyone goes back intrim to where it was torn out, they may or may not find the section there.

By mifortune in occult matrixies

Occult matrix gone wrong, gets interputted, goes out of control
or a regrettable side effect:

EG by summoning this angel, in its passage from its storage at the birth of the universe it clipped though the time stream tearing free a section from a few decade ago.

By design:

Some occult matrices are time sensitive. Sometime the god machine might find it worth-whild to fake setting back the clock so it can trigger them when it wants

I once had some Beta software that would expire and be unable to be used after a particular date. I found out by accident that setting the system clock back a few months made it keep working
the god machine may choose to do that to reality.

There are many uses for a time splitter, in and of itself even.

What Purpose does Time Travel serve in the out of character:
To repeat a section of the above quote:

Time travel in a horror game
  fits as a subset of  Universal Machinery, above, showcasing a story
  where the slightest wrong move can have terrible  unforeseen
  consequences

As well as bringing something new to the game - part of the feel they were going for in demon.
Splitters partially fill a need for Demons to have somewhere to build a hell. (as mother damnable has). Sure not all Demons have a dream of a physical Hell, and some others may find there own paths, to other realms or to walled compounds under the sea. But spliters are present and available, unless they are not.
If you don't like splitters, if you don't like angels or infastructre messing with time.
Then don't put them in your game. It will not break the system.
The first short demon campaign I ran was all about a Splinter.
The demon campaign I am running now doesn't use them, or any other time travel mechanics, at all.
Comment: @Sandwich I am not certain I've encountered such things in demon. Do create your own answer with them, because I am unqualified to add such to mine.
Also this answer is already too long (It could do with some editting)
Comment: I think adding some information about stable time loops and other methods of stopping a time paradox would improve this answer.
Comment: A stable time loop can be engineered with any type of time traveling, essentially the easiest way is that the time traveler themselves caused the initial event to happen, such as an object in the past belonging to the character disappearing because the character himself stole the object himself. So the events that caused the time traveling in the first place resulted in an event that was part of history all along.
Comment: @Sandwich That can be hard to engineer in a roleplaying game - Do you have any anecdotes you could share?
Comment: For example, lets say that history states that a demon you're hunting was banished in the past by a group of heroic persons. It turns out that due to time traveling the group that banished the demon in the past is actually your player characters. The demon now seeks to return to hunt down the "ancestors" of the PCs, which are actually the characters themselves. That's a stable time loop.
Comment: Demons (in Demon the Descent) are immune to banishment (just so no-one is confused). It is also very hard (though not impossible) to get into a timeline that is linked to yours -- as described in my answer, in DtD you normally travel to parallel timeshifted worlds. (Or are timetravelling <15 minutes into the past)
Comment: For the missing citation: the description of angels in the God-Machine Chronicle mentions "cavernous chambers folded neatly into impossible spaces," and the letter written by Stephen Escher says the insides of room 913 "go on for miles, far beyond the inside of the building."
Comment: One possibility for the GM's desire to remain hidden is that it is from the future and is trying to preserve the time-line in which it comes to be created.  Since the world is chaotic, this means huge amounts of processing power and lots of obscure tweaks to keep things on the path that leads to its own future. It would explain a lot of the GM's obsessions.


Do guitar strings wear when not used?

Question: Do strings wear because of the pressure applied to them or any other factor, or do they stay in quite the same shape as long as you don't use them?
Comment: For classical and flamenco, in my experience, and I play a lot, classical strings lose their tone after a few days. But I play about 5 hours per day. I play for a living. I tend to change my strings every 3 to 4 days because they lose their tone and sound dead and dull. Plus they lose their brilliance and projection. I can't stand that sound.
Answer: It depends on how you keep the guitar; the higher the humidity the more likely the strings are get get rusty and tarnish; in fact the whole guitar needs extra care in those conditions; good rule of thumb is if the guitar is not to be used keep it in a dry place at room temperature in a case if possible.
If you keep the guitar in good conditions the strings will take years to wear out if not played.
Comment: The flip side of this is, I leave my guitars out. The less I play the guitar, the faster the strings seem to go compared to the ones I play a lot. I could store the guitars properly, but then I'd **never** play them!
Comment: I used to keep my guitars in their cases. When I switched to having them on the stand, plugged in the amp all the time, I started playing a lot more often than I did before.
Answer: If you get sweaty hands when you play the sweat will remain on the strings and cause them to corrode. Give your strings a wipe with a cloth after you play and this should help to mitigate the problem. You can also get string cleaning products but I don't think much of them.
Comment: +1 for this. Absolutely! Fast fret before playing, and a rub down after - they last so much longer!
Comment: I agree.. I'm convinced its sweat/grease from hands that wear out the strings more than the tension itself. Oxidization or exposure to air and humidity plays a part as well. I would guess the strings rubbing against the frets also contributes to a lesser degree (metal on metal will always cause wear to some extent). A wipe down after playing will prevent the worst of it (either with a clean dry cloth or special string cleaners), but nothing beats just regularly changing the strings. Also +1 on the coated strings recommendation. Elixirs last longer in my experience, and there are other brands.
Answer: How do you know if you need new guitar strings?
For Acoustic and Electric guitars
Couple of questions to answer:
1) Have you had the same strings on for over 2 months?
2) Are your strings rusty?
3) Are your strings rough?
4) Do your strings sound dull?
5) Had a string break recently?
If you answered yes to any of the above, its probably time to replace your strings.
Because of moisture on your fingers and in the atmosphere, strings corrode and rust over time and their ablility to vibrate diminishes. This not only causes the sound to dull but even worse, the feel of the strings becomes rough and will hurt or even damage your fingers.
Strings can also become brittle from too much vibration, just think of how a paper clip snaps if you twist it too much, the same happens to strings - especially if you use a lot of different tunings.
If you play a lot, say for 2 hours a day every day, then you should look at changing your guitar strings every month.
If you play less, but still strum most days, the max you should leave them on the guitar would be 2 months.
Strings are quite cheap, about £5 for a set of 6.
There is an alternative to changing your strings this often. You can buy coated strings. These last longer due to a coating on the strings that prevent dirt build up and corrosion. Coated guitar strings tend to last 3 to 5 times longer than normal strings, so you can leave them on for longer. These still need to be changed though. At least every 6 months these should be changed as they are also prone to breaking because of the vibrations of the string as explained earlier using the paper clip analogy.
Coated strings do cost more, about £12 for a set of 6, but last longer, so can work out more cost effective.
Ernie Ball Coated Strings have titanium reinforcement to make them stronger and less prone to break.
For Bass Guitars, the strings are much more substantial and tend to last longer and hold their tone. Change bass strings at least once a year.
For Classical Guitars with nylon based strings, again because of the way they are made, they don't rust, so last longer. They do age though, so do need replacing. When they age they tend to stretch and become hard to keep in tune. If you don't want to wait till this starts happening, you should look at changing them every 3 to 4 months.
So to summarise:
Change your Electric / Acoustic uncoated strings at least every 2 months.
Change your coated Electric / Acoustic strings at least every 6 months.
Change your Bass guitar strings at least once a year.
Change your Classical guitar strings at least every 4 months.
Comment: This answer was edited to remove the link to your shop page; but other than that this was a great answer, thanks.  In addition, please do not duplicate your answers across multiple questions, a link to this answer in the other questions comments would be fine.
Answer: In my experience, old strings start to weaken at the nut or on the bridge, basically where they are stressed by pressing against the hard surface. They develop a kink at that point. This means that when you try to fine tune the string, it "jumps" suddenly to a wrong note just either side of the exact right note, and it's a killer trying to get them in tune.
And I think this happens regardless of whether you're playing it often.
Comment: As a separate datum - mine always snap at 9th or 15th fret, as that is where I do the most bending, never anywhere near the nut or bridge. ymmv :-)
Answer: This sadly happens to me quite a lot. I have hyperhydrosis so my hands sweat quite a lot and I find if I play for a bit then put my guitar away and come back to it in a couple of days it shows signs of rusting. While not everyone suffers from the same problem as me, I'm sure even a small amount of sweat from the string friction would be enough even if you don't notice.
Answer: Strings can last a long time but lose their quality long before they break -- playing a guitar 7 days a week can wear strings down and cause them to lose the "brightness of tone" within a week. Wiping down with a special cloth after use can keep rust and wear away but it's an uphill battle.

Do guitar strings wear when not used?


Numerical Methods for the Schrodinger Equation

Question: We are comparing the performance of various numerical methods that can be used to solve the Schrodinger's Equation for the Hydrogen Atom interacting with a strong laser pulse (too strong to use perturbation methods). When using discretization schemes for the radial part, it seems like most (all) people put the atom in a box, just chopping the radius off at some large value and solving for those basis sets. How does this compare with mapping the radial variable to a finite domain, and then discretizing that domain (in the process, throwing out most of the basis sets available)?   Is there a reason nobody seems to do that?
Comment: The reason is probably that taking the box large enough will not influence the results at all for the given numerical accuracy, so nobody bothers with mapping the variable. However, a simple google search revealed for example this publication: http://dx.doi.org/10.1137/S1064827596301418 that deals with mapping the infinite domain to a finite interval.
Comment: What is the functional form of the pulse? I don't see why this can't be solved nearly analytically.
Comment: @Jeff: The pulse is likely too short to use Flouquet methods, and even if they could be used I suspect that the OP is interested in other species besides the H-atom.
Answer: Baker et al. proposed such a mapping for a radial grid for atomic & molecular electronic structure computations in 1994. It is still used in modern electronic structure codes, e.g. FHI-AIMS uses them, as described in a recent paper.
Even with such a mapping, the same problems still remains: if something interesting should happen beyound the outermost grid point, you will miss it. However, these mappings do have the advantage that the grid can be systematically improved toward the inclusion of distant grid points. (This is explained in section 4.1 of the recent FHI-AIMS paper).


Crack in paint seems to be slowly getting longer

Question: I have a crack in the paint that seems to be getting larger over the years.  It doesn't seem to be damp.  Could this be something serious or just shoddy installer work?
Comment: Or this? https://diy.stackexchange.com/questions/58369/what-could-cause-a-crack-in-the-drywall-where-the-wall-meets-the-ceiling
Comment: are there cracks on the other side of the wall (if it's an exterior one)?
Answer: Unfortunately many of the homes built in the 80s and 90s have features such as vaulted ceilings and floating walls, and they usually employed engineered truss systems. Those trusses move seasonally due to temperature and moisture changes, and builders hadn't yet worked out how to handle that movement.
In later years devices like isolation channel and expansion joints were installed, which allowed for such movement without drywall damage. Your house (and mine) lack these preventative measures, so we get cracks that come and go.
You have a couple choices, if this in fact the problem you face.

Ignore it.
Rub some paintable caulk into the cracks, then paint. Press firmly and don't leave caulk on the surface to create ridges or seam lines. A lightly damp cloth can help. Such caulk shrinks as it dries, so you may have to hit it twice.
Re-tape those areas with fiberglass mesh. Obviously this requires re-texturing and full-wall painting. Stronger setting-type joint compound (like EasySand 90) for the initial tape coat would be a good idea. Pre-mixed mud is easier to finish with.

All that said, I'm speculating. If you have reason to think you're in a termite area or have larger foundation issues, bring in an expert to look with real eyes.
Comment: Yes, but engineered trusses dramatically enhanced the tendency for lift to occur due to their very rigid structure and connections. The rafters in my 1950s home, by comparison, had nailed connections that had worked quite loose after 60 years.  Also, they made it easy for builders to offer dramatic roof and ceiling features, so these issues became more common.
Comment: Paintable silicone doesn't suffer the same way that regular painter's caulk does and it allows for joint movement of about 25%.
Comment: It's common even in homes that don't have trusses. *Any* house that settles (so, every house) after drywall is taped and mudded is going to have this problem eventually.
Answer: I had something similar, only horizontal. A hairline crack that slowly got bigger/longer, and was almost a perfect straight line. Turns out, it was the paper drywall tape letting go from the sheetrock. The builder didn't get enough mud behind the tape to make it adhere properly. Granted, it held well enough for about 12 years.
It's hard to tell from you pictures, but it looks like the same thing. The second picture even looks like you can see the tape's outline telegraphing through.
I ended up cutting out the bad tape and replacing it with fiberglass tape, re-mudding it. Took a little artistic approach to get the texturing done right, but it looks pretty darn good. Mine was a small area, about 8 inches long. In your case I'd consider calling a drywall professional.
Comment: This is a good suggestion in general, but here we can plainly see the deep cracks and tearing that only come from movement.
Answer: Isherwood goves some good options here.  One thing I've done that seems to have solved a similar issue over the last couple years was to take a utility knife and open the crack into a V-shaped 'trench'.  Someone had previously attempted to use mesh tape which I removed entirely.  Then I layered in joint compound over a few days to fill the  crack level with the wall.  Then I put a little spray on texture and painted to match the wall.  I haven't seen the crack since.
It's important to not fill in crack all at once.  The joint compound will take forever to dry and it will shrink.  Fill in a little and let it dry completely before adding more.  I would also advise against overfilling and sanding.  You don't want to spread all that dust in your house.  Try to get it basically smooth with a putty knife.  Light sanding is all that you should need.
Update:
I thought a little more about why making the crack wider is important.  I had never really considered why, I just got the idea somewhere and it works (every time, in my experience.)  So here's a hypothesis about why it helps which essentially comes down to geometry.  To simplify the model, assume we have two pairs of nails on a wall separated by a crack which we have connected with an elastic band.  Like so:

It doesn't really matter what the units are here but let's say millimeters.  One band is 1mm long the other is 4mm.  They both have neutral tension in this position i.e. they are not stretched.  These bands are flexible to a point.  They can be stretched to double their neutral length but beyond that, they will snap.
Now imagine the right side of the crack shifts down 2mm.  Now things look like this:

The longer band has been stretched 13% of it's capacity.  The short one is stretched to 120% of its capacity.  This is beyond its limit and is expected to fail.  Obviously joint compound is not an elastic band but it's a flexible bonding agent which will fail when it's stretched significantly.
So when you fill a tight crack with something flexible, it's like the second (closer) pair of nails.  When you open the gap wider before filling, the situation is more like the first pair.  It's generally not feasible to control the vertical movement but you can reduce the stress by widening the gap.  It's going to be hard to finish a wide gap filled with caulk so that's why joint compound is used here.
Whether you tape this is up to you.  I know it's recommended and I see a lot of people claiming you will definitely get cracks if you don't use it between drywall sheets.  I think that might be a slightly different situation and I've found mesh tape in a few failed crack repairs in my home.  I used this method with no tape to good results.  My walls are mostly plaster over lath-board, though so that might make a difference here.
Here's a picture of the repair I made a couple years (or more) on.  You can see where I made the repair here because I didn't get the texture quite right (it's an art, for sure) but no cracking to be found.  I wish I had a pre-picture but I did find a hairline crack in a different spot that wasn't repaired this way.  Perhaps when I get that one, I'll document it for posterity.
Comment: I'm surprised a repair with no tape is holding. That sounds like a sure fail. How long has it been?
Comment: @isherwood 2 years at least. I'm fairly certain the cause is seasonal movement.  The prior repair with tape didn't work at all.  The tape just popped the paint into quarter-sized chips as the wall moved and I think made things worse.  I'm not really sure how tape helps here, it's never going to prevent the movement.  What you need is something that will accommodate the movement.  I think I got this idea from Ask This Old House or something.
Comment: No, it won't prevent movement, but there's a reason joints are routinely taped. :) Even without structural movement I'd expect a hairline crack after a while.
Comment: @isherwood It's really crucial to open up the crack which might seem unintuitive.  My prior home had a lot of really bad cracks like this that opened up every year and I had a lot of opportunities to try things including mesh tape and rubberized sprays.  This has been the most reliable fix I've found.  Next I get to try to solve for improperly installed crown moldings : |
Comment: @isherwood Yes, good advice but I don't want to cut new ones.   They are installed with butt-joints along a long ceiling so they open up every winter and the joints are all cruded up where someone tried to caulk the gap.  I'll be posting a question one day.  I also think I have some idea why opening the gap helps with the wall cracks.  I'll update the answer with the reasoning.
Comment: For deep fills you can just use a setting compound like durabond and fill it all at once. Then cover with paper tape and finish
Comment: @redlude97 I appreciate the input but I can't confirm that gives the same results.  For all I know the process of layering could be crucial.  This is one of the advantages from a DIY perspective.  Taking 15-30 minutes a day to apply to do this over a week is no problem for a homeowner but it's not something many contractors would be able to do, unless they are there all week for other reasons.
Comment: I am also just a homeowner, setting compounds are less prone to crack and provide better adhesion than compared to drying joint compound. In the case of durabond it has glass fiber reinforcement as well in the powder
Comment: @redlude97 Interesting.  I would think that having glass fibers would make it more rigid, though. That's undesirable here, I think.
Comment: The fibers make it more rigid and more crack resistant. It is not like joint compound is flexible either, it is both rigid and weak/crumbly
Comment: @redlude97 So when it says 'flexible' joint compound on the packaging, you believe that's a fraudulent claim?  You should file a FTC complaint about for false advertising.
Comment: Can you post a link to the product you are using? What most people refer to as joint compound ie usg all purpose is not flexible. It sounds like you are using a vinyl patching compound


Update results in failed DB check

Question: In trying to upgrade to Civi 4.6.3, I did a backup using Drupal 7.35 (I know, updating that was next) Backup and Migrate, then copied the Civi code files to my desktop, deleted the old Civi, copied in the new Civi, and got an error message that says "Database check failed - the database looks to have been partially upgraded. You may want to reload the database with the backup and try the upgrade process again."
So I did that, using both the backup I had just made and a previous one. Same error message both times. In delving into the Advanced Settings on B&M, it appears that the default only backs up the Civi database. I modified it (I think) to backup the Drupal database as well, backed up the whole site (with the reportedly incomplete database), hoping that what was "incomplete" was the Drupal portion. Same error message every time I start Civi.
What can I do, short of asking my ISP to restore the whole site to a time when I wasn't messing with it (I'm even more ignorant with MySQL).
I know it advises always trying updates on a development site first, but my desktop is Windows and the ISP is Linux. IF I have to, I'll upgrade my contract to give me another site, but I'd probably run into the same problem there.
Civi seems to work just fine, but there is that disturbing error message and I am disturbed enough as it is.
Thanks for any help.
Answer: Are you sure the problem isn't already on the "old" site?
Could you try to (without changing any code) go to the civicrm upgrade page on the old site (/civicrm/upgrade). do not upgrade, just look at what's on the screen
Do you have a message saying you are already at the correct version and nothing to be done?
<code>Sorry but we are not able to provide this at the moment.
Your database has already been upgraded to CiviCRM [your version]
</code>
... or do you already have a message saying database check failed?
If the later, it means that you had a partial update already that was never properly sorted. It's recoverable, but you might have to dig into sql more than you'd like (or hire an expert to help you, probably an easier option to help you untangle the situation)
Comment: Thanks for the quick response. The actual codebase update seems to have worked. I also had gotten a (fleeting) message about some problem involving InnoDB, so maybe it was a MySQL configuration problem. I think I am just going to export the Contacts list (the only thing that has changed much lately) to .csv and ask my very-forgiving ISP to reload the DB from backup.  Incidentally, I learned in trying to figure out what went wrong that Drupal's Backup and Migrate module's default settings only backed up the Civi DB and not the separate Drupal DB. So maybe that is the problem. Thanks again.
Comment: mff, "Database check failed - the database looks to have been partially upgraded." doesn't sound good to me. Ignoring it is going to be biting you in your whatever part of your body you don't want to at the next upgrade I'm afraid...
Comment: After messing around with WP, I'm back to Drupal and trying to test the idea of exporting the Contacts data to CSV, then loading a backup from back before the glitch occurred (which may lose a lot of Contact data) and then importing the CSV. My ISP may be able to selectively restore the DB, but I want to have the Import option in case he can't. The problem right now is that the Civi Contacts Import screen on my desktop version will not accept the Contacts exported from the on-line version. It lets me browse and specify the CSV I downloaded, but when I hit "Continue", it throws an error message

Update results in failed DB check


How can I make a directory accessible without putting it on a menu?

Question: I want users to be able to download a file from my Joomla website, but I don't want the URL posted anywhere on my site. How can I make a file downloadable without adding any links to it from my site?
Answer: Obfuscated File Name
You can upload a file to the website e.g. at website.com/obfuscatedfilename.pdf and then notify users of the file location via email.
Users can then download the file by browsing directly to it and selecting the option to download the file.
Restricted Content
You could add the link to an article and only allow access to the article for registered users. Create accounts only for users that need access to the file.
You could implement a similar solution using a third party download manager extension.
Answer: If you're using Apache, you can also make a directory indexable by editing the .htaccess file in that directory.
Just make a file in your directory called .htaccess. The file should contain the following (and whatever other apache options you want):
Options +Indexes


Appropriate response to an anonymous attempt to hack my servers

Question: If I identify an anonymous attempt to hack my servers is there an appropriate response? Or is it a case of look at what they were attempting and make sure we're covered against it and similar attacks?
Cheers,
Robin
Answer: The appropriate answer depends on a lot of things.
First, it's important to realize that the vast majority of attacks against servers are not performed directly by a malicious "hacker", but by a compromised machine.  Your response should be to using the DNS whois info about the source to get word to the owners of that IP that there are attacks coming from their network.  Most likely, they either have a compromised machine, or a malicious user, and both they will take care of internally.
Second, analyze the attacks and ensure that you've taken appropriate measures to guard against them.
Answer: You must be new to network security.
I can't even count the number of times our servers receive hacking attempts per day. It's basically a normal part of incoming traffic on the internet these days. Not only can you expect this traffic to be coming from compromised home computers, but you can expect entire networks of them working together just like SETI@Home, except bigger, and on an involuntary basis.
I'd say the vast majority of these "botnets" are used to send spam and run scams, the volume of which is entirely overwhelming.
The appropriate response is to make sure that you're not vulnerable (which is more than likely if you can actually detect the attacks), and if at all possible, restrict access to only a few IPs of those people who are allowed to have access in the first place.
Answer:
Is it a case of look at what they were attempting and make sure we're covered against it and similar attacks?

Yes, certainly do this.
Whether you choose to report such unsuccessful attempts really depends upon how much time you have upon your hands. The accepted convention is for network operators to operate an abuse@ address on their domain and detail this, plus any procedural information, within the inetnum entry of their RIR for any address ranges which they are responsible.
You can retrieve this information from the relevant RIR by performing a whois against the would-be attacker's IP address. Don't trust the reverse-DNS of the IP because it can be easily spoofed to an unrelated domain or hostname.
The reality is that most attempts will be generated by distributed and automated utilities operating from networks which simply won't follow up abuse reports. If you're feeling particularly vigilant then you can send reports. But chances are, unless the IP resolves to a well known organisation, your time would be better off spent protecting yourself.
Answer: Your response depends a lot on the vector they were using. For example, I had a VM on Rackspace Cloud that was being constantly hit with SSH attempts. So, I added some IPTables rules to only allow SSH from my IP's. Now, if the vector was web serving that you want everyone to see, obviously restricting it would not be the answer.
Answer: find the Abuse email address related to that ip and send an email warning that there are attacks. provide logs. you can use `whois' to get information about an ip/domain
Answer: You need to audit any change to your files, audit your code, make sure you sanitize any inputs. you can limit the risks by running your http server chrooted/jailed or/and use a IDS plugged in a monitor port of your switch.


What does a coinbase output script look like?

Question: What does a coinbase output script look like and how would it be used to fund a transaction?
Answer: Coinbase transactions are almost identical to normal transactions.
The only difference is that they have exactly 1 input, which must have a special form (which would be invalid for non-coinbase transactions).
There is no difference between the outputs of coinbase transactions and others*. So just like any other transaction, they can have 1 or more outputs, and all those outputs have an amount and a script (address). Each of those outputs result in a new UTXO that is spendable by anyone who can sign for that script/address.
(*) Coinbase outputs have a special rule that they can only be spent after 100 blocks, instead of immediately. This is to prevent reorganizations from wiping out whole sequences of dependent transactions.


how to edit etc/usb_modswitch.d?

Question: Hello I would like to enter a text file with some code in this directory(etc/usb_modswitch.d). How can I do this? please help me. I have try to do this by just move the file but it's a root directory so I got the message permission denied! So How can I become the root and able to copy paste a file there or is it possible to to do this changes by using terminal?
Thanks.
My os is ubuntu 11.10 version.
Comment: Possible duplicate of [Editing /etc/grub.d/40\_custom](https://askubuntu.com/questions/674736/editing-etc-grub-d-40-custom)
Answer: Open a terminal by pressing ctrl+alt+t (don't worry, you'll use it only to invoke the text editor with sudo privileges).
On the terminal type:
<code>sudo gedit
</code>
press enter and input your password when prompted.
Presto, the gedit editor should be running with root permissions!

how to edit etc/usb_modswitch.d?


Quiet 7200rpm hard drive

Question: I'm adding a 7200rpm 3TB data drive to my desktop.  I have a long list of drives with 64MB cache and SATA-3 connectors, but what I really want to know is which will be quiet – in particular the read/write crane movement.  I've had everything from drives that sound from the other side of the room like marbles rattling around in a cement mixer to drives so quiet that I have to press my head against the case to hear that the heads are moving.  Since there are a large number of makes and models of drives that satisfy my performance specs, how can I select ones that are likely to have quiet R/W performance?
Comment: I know you already have some answers, but for me I've found that using rubber grommets supplied with the drive caddy work wonders. My Fractal Define R5 has 4x 500GB 7200 RPM drives in, and I can't hear any of them clicking away.
Answer: It's a bit tough finding exact decibel ratings on different hard drives, in general the dbA is not listed under the hard drive's specifications. But I did find one site where sound measurements were taken. The only issue is, it may be a little outdated (October 2014 was it's last update). But, if we assume that the manufacturers and model types are similar in sound to the ones on this page, it seems that Seagate Barracuda's make the least noise. There are also some other options if we go by the chart I linked to above, so if the Barracuda isn't a good fit, you could go by some of the other ones listed.
That being said, I also did find some HDD "silencers" which would effectively allow you to use any HDD you'd like, although it would take a little bit more fuss. I found a very nice looking one here. There are also other dampeners from the same site here.
Comment: The Seagate Barracuda 3TB is quiet, but it's also *extremely* unreliable.  [Backblaze's reliability study](https://www.backblaze.com/blog/hard-drive-reliability-q3-2015/) shows a 30% failure rate, and I'd love to know how they got it that low -- my personal experience is a 100% failure rate (six drives from three batches, none lasted more than two years).
Comment: Also adding some sound dampening material to the side panels, as well as bottom and top of the case helps as well, and is an inexpensive fix.  If all else fails, one could just use old egg cartons and make a partial anechoic chamber for the case.
Answer: On further research I found several claims that 3.5" 7200rpm drives are a lot harder to keep quiet than sub-6000rpm drives, and that there is no longer a significant performance benefit from the higher platter speed (I suppose because data density is so high that the linear speed under the head is no longer a limiting factor?).
So I expanded my search to 5900rpm drives and found an $80 Toshiba DT01ABA300V that includes "low acoustics" under its design features.
I put it in my chassis and have been running it for a few days and haven't heard a thing.  So for quiet this does the trick!  (How is its R/W performance?  Well I use a SSD for O/S and programs, so I don't know if I would notice even if it were markedly deficient....)

Quiet 7200rpm hard drive


Diminished Intervals

Question: If I go from F# to D# down (F#-D#) is that a diminished third or augmented second interval?
I am composing in minor mode and want to know because augmented intervals are forbidden in part writing.
Comment: d# minor is relative to f# major, hence d# to f# is a minor third.
Answer: It's actually just a minor third.  D# to F## would be a major third, therefore, D# to F# is a minor third.  A diminished third would be D# to F.  Besides, you wouldn't hardly ever use an augmented interval to descend in a voice, but ascending would be more likely.
Answer: I seem to remember (far too many years ago) my theory teacher stating flatly that the names of the notes define the interval, e.g.  C-Ebb is dim3 but C-D is major2 .
Answer: In equal temperament it can be either, depending on the context. If you're writing a descending D#-minor triad it's a minor third. If you're writing a descending harmonic G-minor scale it's an augmented second. You should actually write it as F#-Eb then although it will sound just the same on a piano, for example. But even pianists may play the interval differently depending on what you write, and might get a little confused if what you've written is not what it should be. If you don't have the theoretical knowledge to decide which one it is, try listening to it. If it sounds tense, it's probably a second. If it's relaxed, it's probably a third.
Answer: You always count from the lowest not up when trying to get an interval. It would in this case D# to F#. If the accidentals are bothering you try and lower each not by a semitone. That should help you get this pesky interval.
D - F is a minor third. D major does not have a F but rather an F# but d minor has an natural F. Hence the title of fitting into the interval of minor. D# to F# will have the same interval as D to F.
Answer: I've always used the lower note as a base to count from.Thus, D# to F# (or even Eb to Gb) is a minor third.If it was to be called an augmented second it could be, but it may depend on the key the piece is in.An example of that section of tune may make it easier to explain.
Comment: I am composing in e minor is it an augmented second in that case?
Comment: @ Tim - after reading your comment a second time I realized I made a mistake in my original comment.  It should read "For the interval to be an augmented second, it would need to be written D# - E##."  Good catch.
Comment: For the interval to be a minor second, it would need to be written D# - E##.
Answer: F# down to D# is a minor 3rd. It is equivalent to an augmented 2nd in distance, but because it is an F down to a D it has to be a third. The equivalent interval as an augmented 2nd would be an F# down to Eb which does exist in the G harmonic minor (pointed out by nonpop) so if you are using that scale it is an augmented second.
The intervals can also be looked at in as inverted where an F# up to a D# would be a Major 6th and an F# up to a Eb would be a diminished 7th.
This distance from one letter name to another determines what the name of an interval is so the key you are in is must know knowledge for analysing intervals.

Diminished Intervals


Are there any tools that enable me to convert sentences to Furigana?

Question: I'm looking for some tool that can help me but I don't know if this exists.  What I would like to do is to be able to convert the output of for example Google translate to a sentence that contains the hiragana for Kanji written in [] after the kanji.
Answer: This PDF describes some of the difficulties in ascertaining how to read the two-kanji name 淳子.  This might provide some hints as to why such a tool is ultimately an impossibility.
Even if we ignore proper names (since these are notoriously variable in Japanese), we find strings like 金山, which could be read variously as かなやま, きんざん, or こんせん, depending on context.
Ultimately, I don't think such a tool exists.  If it does, its capabilities are probably restricted to those sets of kanji-spelled words that have single unambiguous readings.
Comment: My thinking was theoretical rather than from any optimism in Google Translate's abilities. I'm quite sure your right that it will still manage to screw things up :(
Comment: If the OP really wants to use Google translate (putting aside the horror of such a proposition) then it provides romaji output as well as Japanese. It should be possible to unambiguously convert this to hiragana. I assume the romaji has the correct readings of the kanji; I've never checked.
Comment: @user3856370, I doubt that Google Translate _could_ have the correct readings for all kanji-spelled words, simply due to the polymorphic nature of Japanese words. For instance, names are sometimes impossible even for native speakers to guess at with any accuracy. Some kanji strings are also hard to figure: 食べ物 is rather unambiguously read as たべもの, but what about if we remove the okurigana and spell it as 食物?  I count eight "official" readings for this in my dictionary, each with slightly different connotations. Google could take a statistics-based approach, but that won't always be right.
Comment: My point is that if Google is translating from the English then it already ought to know which meaning of a kanji it is intending to use so there should be no ambiguity.
Comment: @user3856370: "ought to" can be a dangerous assumption. :)  See, for instance, the oddities described [here](https://japanese.stackexchange.com/questions/66672/morning-afternoon-night-kanji/66673#66673) regarding Google Translate's inability to correctly identify a kanji term.  While English input and Japanese output might be more likely to produce a correct reading, I'm not sure I share your optimism at present.
Answer: Unfortunately getting kanji readings right is not an exact science,  but you can get some approximation by using the text glossing feature in WWWJDIC (and few other similar sites/apps). You'll likely quickly see missing or wrong readings for many kanji combinations.


Why does my fan not work?

Question: I've got a Nissan Micra E 03 reg & the problem is my fan doesn't work on settings 1 & 2 but does work on settings 3 & 4. Could you please tell me what has happened. Thank you.
Answer: To elaborate on user4546's answer...
The heater fan is controlled by a resistor pack located somewhere under the dashboard. This usually has 3 resistors for settings 1, 2 and 3, with setting 4 being a direct connection. With time, these resistors burn out and need to be replaced - and they almost invariably burn out in order, so setting 1 will fail first, then 2 (and you have seen) and so on...
To fix it, you can either replace the entire pack, or, in some cases, have the individual resistors changed. I can't tell from a quick googling if this is possible for that age of  Micra, but new resistor packs seem to be available from Nissan or various online suppliers - make sure you get the correct one, as it looks like '03 was the changover year between two generations of Micra (K11 and K12)
Answer: Sounds like a bad blower motor resistor
Comment: For a Micra, of course! You'd get one cheap off a breakers as well - they're very popular cars, so every scrapyard has one
Comment: This sounds like the problem to me as well. You should be able to pick one up off of the internet fairly easily.

Why does my fan not work?


Converting names to Japanese

Question: I am a Japanese learner and I would like to know how my name is in Japanese. My name is Bill and I have seen the translations "ビル" (biru) and "バジル" (bajiru). I am aware that バジル means "basil" but I use it most of the times. Can you please help me?
Comment: バジル seems odd to me; I don't think I have ever heard it as a name. I would certainly stick with ビル (unless, of course, your name is pronounced somewhat akin to basil in English).
Comment: @Ben Steffan Thanks for your advice! ありがとうございます!
Comment: @Blavius my bad, deleted the comment
Comment: This could be a funny website for you: http://www.kanjizone.com/kanjiname.aspx?name=Bill

Anyway, I'd go with ビール. Definitely funnier than ビル. :)
Comment: @Tommy Haha!  Yeah!  Very funny!
Answer: ビル is a good transcription of the name Bill. This website confirms the match: http://apps.nolanlawson.com/japanese-name-converter/#?q=Bill
Example:

なぜウィリアムのあだ名がビルなんですか?またなぜロバートはボブなんですか?

This is from a yahoo question website.

Why is Bill a nickname for William? Also, why does Robert become Bob?

You're quite right about バジル being the Japanese word for basil - it would make you sound as though you were named after a herb. More to the point, it doesn't sound anything like your name. ビッル might be another transcription, but this seems strange to me and I can't find any examples of it being used.
Incidentally, ビル could also mean a multi-storey building or a bill, as in check, invoice, paper money or beak of a bird - these are loan words from English. https://ja.wikipedia.org/wiki/%E3%83%93%E3%83%AB
Comment: Can I also use ウィリアム as Bill is the short/nickname of William?
Comment: If you want people to call you ウィリアム, that seems quite all right to me. A google search of ウィリアム brought up links to Prince William. In Japanese I sometimes go by ロブ and sometimes ロバート. I prefer to tell people the former, because it's easier to pronounce.

Converting names to Japanese


Where to post questions that might not fit serverfault?

Question: I have a issue with high system cpu usage with qemu but because i use a panel (virtualizor) that (probably?) doesn't fit on sf. I mainly just dont want to get downvoted into oblivion because "it doesnt fit 100%" Is it safe to post or should i be looking somewhere else for support (virtualizor support already gave up on it as it "wasnt their software causing the issue")
Comment: from my experience having one bad question leads to a ton of downvotes which leads to you not being able to lose all features. That is why i generally dont like using Stackoverflow but as i was denied support in most other placed i thought i'd give it a chance.
Answer: If you're using a panel, do you have a provider, or did you set it up yourself? Talk to your provider's support staff.
Alternatively, there are some coding/IT fora around. Reddit might be a good place to look.
Comment: I used virtualizor but they were not able to help that well as its 'not their software" and QEMU support is also very inactive. I can try reddit but as it looks like a quite advanced issue i doubt that will help much


How (un)suitable are veterinary products for human health?

Question: We've all seen movies in which gangsters are treated by (paid or coerced) veterinarians in order to avoid law enforcement in hospitals. How bad are animal-grade pharmaceuticals for human health, in real life? I assume that they are held to decent standards of purity, and sterility. How do these compare to human-grade drugs? Are they OK, say, for emergency situations?
Comment: I don't have a specific drug in mind.  If some types of medicines are held to the same standards as those for humans, and others not, then an explanation of why that is the case would certainly be the starting point of a good answer to this question :)
Comment: This is a good question. For example, suppose I have bronchitis but can only obtain horse antibiotics from the local farm supply shop. Assuming I match drug, dosage, route, etc., how much of a "risk" am I taking on? I recognize that this would hardly ever be clinically recommended as a best practice, but can the risk be quantified or at least described in a coherent way (e.g. 2% greater chance of being poisoned by impurities, 0.5% chance of having a seizure from veterinary-specific binders and inactive ingredients, etc.), or is "don't do it, it's baaaad" the most anyone can say?
Comment: More often than not they're the same drugs. I've owned dogs most of my life, and probably 95% of the prescriptions we give them come from the same drugstore we get ours and they're the same drugs. That said, it depends on the drug in question. There's no answer to your question because it's too broad.
Comment: Can you find a way to narrow it down to a specific drug or class of drugs?
Answer: Some problems with using veterinary drugs by humans:
1) It's illegal.

Any deviation from the label, by veterinarians or lay persons is an
  illegal use...(American Veterinary Medical Association)

2) It can be harmful for your actual condition.
If you wrongly self-diagnose yourself, a certain drug that is not intended to treat your actual condition, can dangerously interact with it.
Example: fish antibiotics:

...most upper respiratory problems, for example, have the same symptoms.
  But many of the diseases are viruses and don't respond to
  antibiotics....taking an antibiotic can complicate the course of that
  event (U.S. Department of Defense, 2002).

3) It can cause significant side effects.
Drugs intended only for animals have not been tested in humans, so they can have significant side effects in humans (due to active or added substances).
Example 1:

Closantel is a halogenated salicylanilide with a potent anti parasitic
  activity. It is widely used in management of parasitic infestation in
  animals, but is contraindicated in humans.
A 34-year-old man with depression was referred to our center with
  progressive loss of vision in both eyes 10 days after unintentional
  ingestion of three 500 mg tablets of Closantel (BMC Ophtalmology,
  2016).

Example 2:

Acepromazine is a phenothiazine that is used exclusively in veterinary medicine for multiple purposes.
A 54-year-old woman intentionally ingested 950 mg of her dog's
  acepromazine. Within 3 h of ingestion, she developed central nervous
  system and respiratory depression along with hypotension requiring
  non-invasive ventilation and vasopressors (Journal of Medical
  Toxicology, 2015).
Comment: Case 1 is not really relevant to biology itself, and cases 2 and 3 are only valid in the case of people taking the wrong drug (e.g. taking antibiotics is useless for viral infections, even if the antibiotics are human-grade). However there are plenty of active molecules in veterinary drugs that are, or have been, used in human therapy; for example ampicillin, lidocaine, isoflurane, and many others. Do you have any insight about these?


How to visualize screen overlaps in Chrome

Question: Is there some way to show the overlapping between two screens in chrome? I usually use "page up" and "page down" when I read on my computer. This works quite well in Acrobat Reader as it detects the last line of the previous screen (or page) and only shows the new content. The worst case is: I have one additional line of old text.
In Chrome a significant part of both screens overlap (usually 5-7 lines). It is very bothersome to find the point where I stopped reading, especially if this is the last portion of the website and the screen shows way more than 5-7 lines of the old text.
I want to have a visual mark where the old stuff stops and the new content begins. Something like this mockup:
Imagine I read this page and I am done reading. I press "scroll down".

As you can see about 5 lines overlap. I want something like the grey line that shows me where to pick up reading.

Does such an addon or plugin exist for chrome? I do not care how the visualization is provided. The old text might be hi-lighted or grey.
Comment: I've exactly the same problem. Could you solve it?
Answer: MagicScroll. Kinda.
Demo, Chrome Addon, Source, HN Discussion (which also mentions Beeline Reader)


How can I protect my savings against inflation? [UK]

Question: How can I ensure that my savings keep up with inflation, even after any tax due is taken off the returns?
Answer: If your primary concern is inflation, you can buy an Inflation-index bond.  This is a widely available bond that many countries offer.  In the UK, this is referred to as the "Inflation-linked Gilt", issued by the UK Debt Management Office.  These bonds will value the investment in relation to a certain inflation index. In the case of the Inflation-linked Gilt, they use the Retail Prices Index.
Answer: In the UK, you could use an index fund or ETF that invests in instruments indexed to the Consumer Price Index. One option is the iShares Barclays £ Index-Linked Gilts (INXG), which

is an exchange traded fund (ETF) that aims to track the performance of the Barclays World Government Inflation-Linked Bond Index as closely as possible.

You still need to take into account commissions, among other factors, and understand that any investment comes with risk. Note that this ETF aims to track the performance of an inflation-linked bond index. It may not succeed all the time. This isn't a fool-proof strategy, unfortunately, because investing is always a trade-off between risk and return. By excepting a higher return, i.e., one that can keep up with inflation, you do bear a higher level of risk.
Vanguard.co.uk has good general information about inflation-indexed instruments and funds too.
Answer: Don't forget to buy whatever you use inside one of the tax-free savings vehicle (ie, some sort of ISA or similar), especially if you're a high rate tax payer. If you don't, the 40% tax on it will pretty much make it impossible to get a return anywhere near the rate of inflation.
Answer: If you don't need the money immediately I suggest some of the large equity income Investment trusts would be a good way of beating inflation Lowland and City of London are two that come to mind.


Can I sell this patented product outside the US?

Question: I'm trying to reproduce this product: https://patents.google.com/patent/US20160324283A1/en but I wondered if I could sell it outside the US since it has the WO patent... Thanks!
Comment: The linked file is an application, not yet a patent. Also, I'm guessing the inventor also filed internationally too.
Answer: That number is the publication number of a U.S. patent application. It is not a granted patent at this time. Looking in the USPTO database Public PAIR, I see that it got a "final rejection" recently. That doesn't mean final; just final until more money is paid to a Request for Continued Publication. From the same database, the PCT application (WO2016179586) is shown as getting priority from US provisional application 14/706,019 filed 05-07-2015. I do not see in Patentscope (WIPO) that any national stage was entered within the 30 or 31 month time frames so the U.S. might be the only place with something pending.
Patent rights are territorial so if a U.S. patent was issued you would be prohibited from making, selling, offering for sale, using, or importing it into the US - only. What this way of looking at the situation misses is that there may be patents in any location that are already granted to this inventor of some other inventor that would constrain your actions in the respective locations.
Answer: In addition to George White answer I would like to add that, if you are trying to reproduce the product in US and then export to other countries then also you would be liable as an infringer if the patent gets granted .


Proper sump pit water level?

Question: I am concerned that my sump pump no longer turns on when the water reaches the appropriate level. As you can see from the picture the water level is about 3/4 the way up the inlet pipes. Which is high enough so that water doesn't really run in. Shouldn't the water level be below the inlet pipes? I bought the house last year so I am not really sure about the age of the pump. I can manually run the pump, but that doesn't really do much good if I were to get a lot of rain I would have to babysit it. Can I troubleshoot the automatic turn on by dumping water into the pit with a bucket?
Comment: What is the second wire? Is it a float switch (bulb or ball on the end of the cable) that should be in the sump?
Comment: According to the discoloration on the sides if the pit, that has been ho high the water stays that I can tell. as long as the water is below those pipes it should do what it is designed for.
Answer: The water should not be that high in the sump. It should be down to around the 2-3" level inside. This is what I'd call a safety margin which allows the pump time to rest should there be any sudden surge of water coming in from the drain tile or where ever else it might come in from (only other place I can think of off the top of my head would be the A/C drain, but you wouldn't get a surge from there). If a pump has to pump continually without resting, it will burn up the motor faster due to heat build up.
There are two things to test. First, find the float switch which should turn your pump on when the water gets deep enough (it should be a ball floating in the water somewhere, maybe under the drain pipes). Rattle it around and see if it will turn the sump on. If it was stuck under the pipe, it may just need to be dislodged. If you rattle it around and the pump does not kick in, it could just be bad float switch, which you can get a replacement for if the main power cord runs through the check ball cord (hard to explain, but there would be a plug within a plug as it plugs into the wall).
The second thing to check is if the pump itself is good (if the check ball does not turn it on). If there is the plug-in-a-plug situation as I described above, pull the two plugs out of the wall socket, pull them apart, then put the pump one (should look like a regular plug) back into the wall and see if the pump turns on. If it does, you can get a replacement float switch and you should be golden for the mean time. If it doesn't, you'll need to replace the pump.
Unless there is a longer manufacturer's warranty on a pump, you should replace them every two years anyway. I would bet this one has not been changed for quite some time. It gives a little piece of mind in doing so. As well, if you do not keep the maintenance up on your pump and the a flood ensues where the pump could have handled the difference, the insurance company might not pay for cleanup and repairs, so this maintenance item is a must in my house.
Comment: A good one will last 10 or more years. If you have great concern, a dual-pump controller and two pumps will soon be cheaper than replacing every two years...especially if you don't buy the cheapest pump around. The warranty won't cover water damage from it failing. The controller will let you know when one dies, and a good controller will exercise both equally.
Comment: @Ecnerwal ... very good points. We have a backup sump after our main one failed, but will look for the dual in the future. The last one which failed I replaced with a 1hp model ... that thing can throw some water ;-) It has a 5-year warranty, but I don't think I'd ever trust a sump to last past that ... just me having had a wet basement a couple of times ... no fun at all.
Answer: Looking in the photo, it looks like this is a Hydromatic D-A1 which uses a Diaphragm float switch. The diaphragm switch looks like it is a older design before 2014, and these ones get stuck after a period of time(Either stuck in the on position or stuck in the off position). The newer switch from Hydromatic in 2014 doesn't have this issue. First what I would do is, with the water level up to the level seen in the picture, get a stick and push down on the Diaphragm switch(The big black cylinder attached to the side of the pump) and see if it triggers the pump.
The next thing I would do is pull the pump out of the pit, and place it outside, then get a pencil/pen and stick this up into the bottom of the diaphragm switch in the center to where a hole is located and lift up the actual diaphragm until you hear a click come from it, next, repeatedly lift up and lower the pen/pencil to get the switch to activate and deactivate, and do this 5-10 times so then the diaphragm loosens itself so it activates and deactivates properly. Put the pump back into the pit and fill up with water. If the pump still doesn't activate, I would order a new diaphragm switch from Hydromatic, or for a cheaper option, get a Basement Watchdog/PHCC dual float switch.

Proper sump pit water level?


how to view your accounts google play store money

Question: I bought a nexus 7 in 2012 and it came with a $20.00 gift card. When I went to install apps from the app store, it asked me to sign into my google account. I signed into my gmail account and received the $20.00 for the play store. I purchased one or two items but I'm positive I still have a good $15.00 left. Where do I go to check how much google play store money I have left on my account? I went to wallet.google.com and it asked me to create a payment method, but I know for a fact that I still ahve a good $15.00 left on that gift card... Do the gift cards expire?
Answer: According to the TOS, Google Play gift cards never expire.
You can view your balance by opening your Google Wallet page (you can also view your transaction history here to figure out where your money went) or by contacting Customer Care at 1-855-466-4438.
Comment: That Google Wallet page actually did show me when my credits expire. Thanks.
Comment: @MGOwen Interesting, I don't see when it expires anywhere.  Where do you see that information?
Answer: Gift cards expire after a year of not being used, I think.
To check their value go to buy an app, and on payment methods, the card will be displayed with the value underneath. Then cancel out of buying the app.
Comment: This information is contrary to the answer provided by @Compro01 above.


Is there any way to experiment with the Bitcoin technology without having to buy actual bitcoins for use on the larger bitcoin network?

Question: So, I'm just a curious person at this point, I've only just decided to look into Bitcoin and see how it works and what it does. But I'm not sure if I want to try out things on the larger bitcoin network, where there's real money of real value at stake. Is there a way I can setup a local bitcoin "network", with its own blockchain, etc. for testing purposes?
Comment: you can check these instructions to setup a local bitcoin network https://blog.starapps.io/setup-private-bitcoin-regtest-using-docker-a406127192df
Answer: Yes. You can run bitcoind in regtest mode. In that mode, you can produce your own "bitcoins" for testing purposes.