Detection of the contours of a measured waveform

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• Align the two signals and measure the Phase Shift

  Hello

  I do an experiment in which I use the NI USB-6221 DAQ card. The jury is able to make 250 k samples/second. I want to measure two voltages in a circuit and find the phase shift between them at frequencies between 1 and 10000. First I ouputted a wave sinusoidal frequency variable through the Commission and applied to a test circuit. Then I used the Board to measure the two tensions consecutively (thus reducing the maximum sampling frequency at 125 k). I used the signals align VI and measured the two phases and then calculates the phase shift (VI attached in Phase 1). It worked well for the test circuit I built in which the phase shift went way logarithmique.20 degrees ~84.5 degrees and then stabilized. At frequencies above 5 000 Hz phase shift must have remained constant, but it varies more or less 1 degree. When the phase shift is 84.5 degrees, present a degree of variability is not particularly explicit. When I asked my program on the circuit that I really wanted to measure, the phase shift went from-. 5 degrees up to about 1.2 degrees. The change in the values of phase shift at high frequencies (> 3000) was environ.2 degrees. Given the small phase shift, this variation is unacceptable. Now I tried to use a sequence to each blood individually (increase the maximum sampling frequency to 250 k) and then align the two signals and measure the phase of each shift. When I use align it and re - sample Express VI to realign the two signals, I get the message "error 20333 analysis: cannot align two waveforms with dt even if their samples are not clocked in phase." Is it possible to align two signals I describe here? I enclose the new VI as Phase 2

  Matthew,

  I think I have an idea for at least part of the problem.

  I took your program data and deleted stuff DAQ.  I have converted the Signal on the chart control and looked then what was going on with the signal analysis.

  The output of the Waveforms.vi line has two waveforms, like the entry.  However, arrays of Y in the two waveforms are empty!  It does not generate an error. After some head scratching, reading the help files and try things out, that's what I think is happening: the time t0 two input signals are 1,031 seconds apart. Since the wavefoms contains 1,000 seconds of data, there is no overlap and may not align them.

  I changed the t0 on two waveforms are the same, and it lines up.  The number of items in the tables is reduced by one. Then I increased the t0 of 0.1 seconds on the first element. The output had both greater than the entry by dt t0 t0 and the size of the arrays was 224998.  Reversing the t0 two elements shifts the phase in the opposite direction.

  What that tells me, is that you can not reliably align two waveforms which do not overlap.

  I suggest that you go to 2-channel data acquisition and that it accept the reduced sample rate.  You won't get the resolution you want, but you should be able to tell if something important happens.

  You may be able to improve the equivalent resolution by taking multiple steps with a slight phase shift. This is similar to the way that old oscilloscopes of sampling (analog) worked. Take a series of measures with the signal you are currently using.  The make enough average to minimize changes due to noise. Then pass the phase of the signal of excitement to an amount that is smaller than the resolution of phase of sampling rate and repeat the measurements.  Recall that I calculated that for a 5 kHz signal sampled at 125kHz, you get a sample every 14.4 degrees. If shift you the phase of 1 degree (to the point/mathematical simulation), you get a different set of samples for excitement.  They are always separated by 14.4 degrees.  Take another series of measures. Transfer phase another degree and repeat.  As long as your sampling clocks are stable enough so that frequency does not drift significantly (and it shouldn't with your equipment), you should be able to get near resolution of what you need.  The trade-off is that you need to perform more measurements and may need to keep track of the phase shifts between the various measures.

  Lynn

• Detect if the time/date browse button has been used

  Hello

  I have a checkpoint vi for the indexing of the elements inside the table and shows the date and the corresponding time. I have the large number of control inside my block signals, but I removed all the blocks out of words and signal for this discussion. I replaced all the unnecessary controls with constant values, so don't waste time analyzing.

  If you take a look at my vi, you'll see Star/Stop control, control of Position and an indicator of time stamp (time waveform) with a browse button date/time of another control of time stamp. I have all the features you want, but I have the problem when you use the button browse to bring up the time. I can't put my time twice in a row to the same value as I compare value "Last entry of time" with a current comes to enter. I wouldn't completely change my blocks because I use a lot of variables and property inside my project nodes. I'm looking for a way to figure out if the time/date browse button was pressed so I could jump to the desired in my registered wave point.

  I'll skip the actual implementation of what you're doing because it's not all that clear to me and answer the question about to detect if the button has been pressed. This general question came several times before in this forum. There is no built-in mechanism to detect that the Browse in a timestamp control button was pressed. When you click this button, it actually opens a VI with the title 'Set Time and Date'. For example, you can monitor to see if this window opens.

• Fluid was detected in the connector of the lightning.

  I get a warning when my iPhone is plugged into its lighting cable saying 'Disconnect accessory lightning' "Liquid has been detected in the connector of the lightning" ' to protect your iPhone, unplug this accessory of lightning, and allow the connector to dry. "

  The cable is as dry as a BONE, the phone has never been exposed to water, other than standard moisture. I have several cables, and it happens with all of them.

  Clues?

  Thank you.

  Try a forced reboot. Hold down the Home and Sleep/Wake buttons at the same time for about 15 seconds, until the Apple logo appears. You won't lose anything.

  If the steps above do not help, you may need to test in an Apple store.

• Firefox has detected that the server redirects the request for this address in a way that will never end.

  This week (01/10/12) I registered on youtube and now I can't log back in here or in my gmail account. I tried every fix-it/single remedy offered the FF forum but nothing works.

  Any other work, all the sites that I frequent load fine, is youtube doing something on purpose for FF users? I can get the page youtube videos and see, but I can't log on, every time I click the sign in button, I get:

  "The page is not redirecting properly".

  Firefox has detected that the server is redirecting the request for this address in a way that will never complete.
  

  This problem can sometimes be caused by disabling or refusing to accept cookies. »

  I hate to be a conspiracy theorist, I can connect to youtube without problem on IE, but I hate this browser. I use windows 7 and 15 FF. Can someone find it?

  Looks like it's a firefox issue, because that never happened on IE, Safari or Opera on me.
  You think not that a simple patch can solve this problem. I have to delete individual cookies every day.

• I deleted my account on a site I'm going and it keeps saing that Firefox has detected that the server redirects the request for this address in a way that doesn't

  He repeated to me that Firefox has detected that the server redirects the request for this address in a way that will never end.

   This problem can sometimes be caused by disabling or refusing to accept
     cookies.
  

  Have you tried to clear the cache and cookies?

  Clear the cache and cookies from sites that cause problems.

  "Clear the Cache":

  • Tools > Options > advanced > network > content caching Web: 'clear now '.

  'Delete Cookies' sites causing problems:

  • Tools > Options > privacy > Cookies: "show the Cookies".

  See also:

  • http://KB.mozillazine.org/cookies
  • http://KB.mozillazine.org/The_page_is_not_redirecting_properly

• I have Firefox 12.0 installed and when I open Youtube and/or Gmail they detect that the browser is obsolete. Why is this happening?

  I have Firefox 12.0 installed and when I open Youtube and/or Gmail they detect that the browser is obsolete. Why is this happening?

  You have a pref general.useragent.override, which identifies you as a Firefox/4.0

  • Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; RV:1.8.1.16; .NET CLR 2.0.50727; ffco7) Gecko/20080702 Firefox/4.0

  See:

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  • https://support.Mozilla.org/KB/websites-incorrectly-report-Firefox-outdated-or-in
  • http://KB.mozillazine.org/Resetting_your_useragent_string_to_its_compiled-in_default

• I got a message that there is an hour: Trojan.Win32.Generic detected in the time machine.  How can I remove it? Is this true?

  I received a message that there is an hour: Trojan.Win32.Generic detected in the time machine.  How can I remove it? Is this true?

  I have the version of yosemite 10.10.5 OSX macbook air.

  Whence this message?

• Satellite U500 - 1 DR series Notebook is not detected by the TOSHIBA site

  Hey,.

  My Toshiba Satellite U500 - 1DR Series notebook (Serial No. 1A058758R) is not detected by the automatic detection of TOSHIBA online system. When trying to get portable detected manually on the site, I stopped fingd the model (Satellite U500-1 DR) is listed in the list of available templates or models. I'm unable to download software/updates on the site.

  Hello

  If the work of autoetection doesn t you can find manually but not not using the name model but the model reference number. Your DR U500-1 has part number PSU9ME-xxxxx then please check under http://eu.computers.toshiba-europe.com/innovation/download_drivers_bios.jsp Toshiba download page and look for Satellite U500 with reference number or model number short PSU9ME.

  Can find you it?

• Firefox has detected that the server redirects the request for this address in a way that will never end. I followed your instructions and nothing works. This just started happening today.

  I was watching www.ustream.tv/decoraheagles for months. I started using Firefox about a month ago. Earlier today, when I tried connecting to the site, I received the message "Firefox has detected that the server redirects the request for this address in a way that will never end."
  I went on your site and follow the instructions. This Web site was not in the blocked sites. He told me how to add it, and I did.
  She still refuses to open this site.
  Internet Explorer WILL open this site.

  Clear the cache and cookies from sites that cause problems.

  "Clear the Cache":

  • Tools > Options > advanced > network > storage (Cache) offline: 'clear now '.

  'Delete Cookies' sites causing problems:

  • Tools > Options > privacy > Cookies: "show the Cookies".
  • http://KB.mozillazine.org/The_page_is_not_redirecting_properly

• IMac-formatted external hard drive is not detected in the window computer

  I had formatted my drive external hard seagate new with the imac. now the problem is that it is detected in the iMac and not in my computer window. kindly help me in the detection of seagate in my computer window

  What format do you have selected?

  Ciao.

• message from Firefox: "page isn't redirecting properly" Firefox has detected that the server redirects the request for this address in a way that will never end. * Why this mess

  "The page isn't redirecting properly?

  i receive this warning on a daily basis. it seems to occur whenever i open a message  in gmail or try to send a message. anybody have a clue about this? thanks!
  

  Firefox has detected that the server redirects the request for this address in a way that will never end.

     *   This problem can sometimes be caused by disabling or refusing to accept
           cookies.
  

  See http://kb.mozillazine.org/The_page_is_not_redirecting_properly

• Satellite M30x + Win7: DVD not detected by the CD/DVD drive

  Hello

  I use a M30x since 2004 with its CD/DVD drive * a S mat. DVD-RAM UJ-831
  When I was with Windows XP, I have never had problems to read or write on CD, CD - R, DVD, DVD - R or DVD - RW. But recently I installed windows seven, and since that day the drive won't recognize the DVD. I can still read and burn CDs and CD - R. I'm burning the same Virgin DVD-+ R/RW as before, but the drive won't detect them. Those I have already burn are not detected or the other.
  My computer says that the CD/DVD drive work properly and drivers are up to date.
  I tried to clean the lens, but nothing has changed. And I tried to reinstall the drivers, but I could not found for windows seven.

  Thanks for the help.

  Hello

  Have you tried to delete the upper and lower registry Filters >
  Pleas check it!
  http://support.Microsoft.com/kb/270008/en-us

  You will find the registry key where filters must be removed.

• HARD drive not detected in the BIOS on Satellite A215

  Hi all

  I could use to solve this problem: bought this laptop computer without a disk of the auction. Installed again 2.5 inches HDD SATA 250 GB, which was not detected in BIOS and also not detected when using a MS Vista installation disc. When trying to install Vista, get a message no drive seen HARD and demand for pilots.
  I flashed the BIOS with version (2.0) of lates without problem through the CD drive, but still no detection of HARD drive.

  The drive partitioned and formatted NTFS without problem by using another computer and USB SATA adapter using the command line method. Just for additional verification, I went on the new HARD drive to an extra 2.5 "SATA HDD used for backups, but that the HARD drive has also not been detected.

  It is not a "compatibility" option in CMOS to select SATA or Auto, etc..
  There is not a second HDD, so this isn't a question of slave/primary. There are no jumpers on the new HARD drive.
  Set the CMOS settings 'by default' does not solve the problem.

  The SATA connectors on the HARD drive and laptop computer are in perfect condition.
  Also, the drive is not detected on the laptop connected via USB to SATA Adapter, but of course there is no OS installed to support this connection.

  In any case, I just can't come up with any more ideas to try.
  Any suggestions would be really appreciated!

  Best,
  Glenn

  Hello

  The BIOS should recognize the HARD disk even if the SATA mode would be compatible or AHCI. This should not affect the recognition of the HARD drive.

  You said that you have tested the condition of the HARD drive and it's ok, so I guess that it s no disc HARD question.
  Hmm, you could try to format the HARD drive once more and then connect the portable computer HARD drive.

  Another idea: Remove/Disconnect the CD/DVD drive and then connect the HARD drive to the SATA connector.
  If it does not, then I recommend to test another HARD drive, otherwise if the new HARD drive would not work, then a SATA controller may be defective.

• Satellite L40 - no HARD drive not detected in the BIOS

  Hello

  I need some advice here. I have a Toshiba Satellite a colleague here, type L40 - 14N. She wanted to run the Toshiba Recovery CD procedure to get back original configuration... system was going way too slow and all that, no other problems. Anyway, she's not very experienced and one way or another the recovery failed.

  Problem is that the system does not detect a HARD drive now more for some reason any. Not in the BIOS, not during the procedure of Toshiba Recovery CD if I start it now. I also tried a Vista installer retail and loaded drivers SATA raid as mentioned on this forum. Without success, no HARD drive detected.

  It's weird, because nothing essentially. Any suggestions how I could solve this problem and get the HARD drive online?

  If the HARD drive is not detected, the installation of recovery will not work and also a Microsoft installation disc.
  The HARD drive should be detected in the BIOS, otherwise that an installation is not possible.

  However, it seems that the HARD drive is defective because the BIOS peut t detect it.
  If your laptop is in warranty got a local ASP or you change the HARD drive by yourself.