How to measure differential analog signals

Similar Questions

• How to convert an analog signal into digital signal

  Hello

  How to convert an analog signal into digital signal, such that each sample of the analogue signal corresponding to 1.2V will be represented as '1' digital signal and other samples of the analog signal (which are not 1.2V) will be represented (converted) ' 0' in the digital signal.

  And how to view the wavefroms or graphical indicators signals.

  Thank you.

  If you have 1000 samples and you want to convert to digital, you get 1000 digital values.  Attached, that's what I mean.

• How to measure multiple analog input at the same time.

  

  I tried to do a VI that controls a motor with two buttons. If I press the buttons, the VI took the analog signal from the buttons and the engine is running. Each button covers the different direction - to the left and to the right.

  I need to enter the two report in the VI at the same time, but I can't. If I run the VI, VI takes only a random signal. I want to know what are the problems and how to solve them. Please help me.

  You must use a single task for both channels.  See if that helps.

  

• How to create an analog signal of a text or a binary file?

  I'm trying out an analog signal of a file on a map of NOR-DAQ 6251 with labview 8.5. I found examples on the construction of a waveform, but I'm stuck at how read a text file and do a 1 d table to enter my amplitudes in the buildwaveform.vi and I can't find all the information on how to do it. Help or direction is appreciated.

  Thank you

  David

  What if all you want in the file corresponds to the values of Y, then a text file with a value on each line can be read. Read from a usable spreadsheet file. It will return a 2D you can then use array index to get a column or if you select Transpose, the array returned by 1 d would be used.

  If you want to create an example, use a 1-d array constant in a VI and pass it to the writing on a spreadsheet file.

• How to use an analog signal to conditionally generate a TTL (or a square function) signal?

  Hello world

  I am using PCI-6229 and try to develop a code that can generate a TTL/place function signal from only one analog entry satisfies following conditions: 1. crossing a certain value (for example, 0 V); 2 slope edge of fall. The time delay between the point of passage and newly generated signal TTL/square will be essential to my measurement, and may not exceed 1 millisecond. Any suggestion on this subject? Thank you in advance!

  You are using the measure called Excel add-in? That's what this forum is for. Otherwise, you should post to the multifunction DAQ card and speak the language you are using.

• Compare two analog signals.

  How to compare an analog signal to another analog signal to see what signal has a higher value? I want to display the result on the façade with LED indicator.

  This will make a simple comparison of A > B. If your code is more complicated then you must set up a system of producer-consumer. You can find examples of this in the supplied examples.

  Here's a sample:

  

• How to generate analog signals?

  Hi all

  I'm trying to generate analog signals to simulate the position of the valve. I also want to simulate the position of the valve 0 - 5V (analog signal).  I've implemented the numeric position of the valve by using the toggle switches, but I want to implement analog signals.

  You can help.

  Thank you

  You can just use a random number generator.

  

  Since you have no generator hardware signals of NOR, I'm not sure why you are posting to this Board. Generic questions of LabVIEW. Post to this Board.

• How can I use my PXI-6115 meter analog signal trigger to generate pulses of frequency

  I work on a PXI-6115 DAQ card and want to using the analog signal to trigger the counter it's generating frequency pulses. The manual says the analog trigger is supported, but I can't use an analog signal to trigger the start of work, in the test, I use the counter 0 to generate pulses and use the signal input port analog trigger PFI 0, can someone tell me what it is? My test VI. & error message appears in the attachment.

  Best regards

  If you read the error you can see digital triggers are the available trigger only when you use the output of the counter.

  You can work around this by setting up a dummy analog input task which will trigger an internal digital triggering when he sees the right analog trigger.

  See this thread for more details:

  http://forums.NI.com/T5/LabVIEW/DAQmx-start-trigger-analog-edge-VI-keeps-returning-error-200077/m-p/...

• filterinmg RF analog signals

  I am writing the control software for a system that uses RF (clocked at 72 MHz) as a major component. None of our signals have harwdare filters and software I am sampling 100 samples at 1 k Hz. I have on average these samples and update every 250ms.

  Using a language I can understand, can someone help me understand how RF may influence our signals and what options I have to filter this noise (harwdare and software). Or at least point me to a good resource.

  Doug,

  Here's the ME version of RF interference.  The combination of transmitter/antenna radio creates electromagnetic waves in the space around the antenna.  Think of dropping a stone in a pool of water.  The wave analogy is reasonable for the basic understanding. A leaf floating on the pond goes up and down with the wave.  If you put a float on the water and connect to the Mainland by a gearbox, you can extract energy from the waves.

  In your DAQ system two things are necessary to produce interference. 1. the RF wave must be coupled to the system. 2. the RF energy must reach a point where a non-linear device converts the sine waves of very high frequency in a form which allows to measure the low frequency DAQ system. (2.a. There are a more complicated way interference can occur without a nonlinearity - subsampling).

  How the coupling can occur? The wavelength of an electromagnetic signal in free space is the speed of light, divided by the frequency.  For 72 MHz the wavelength is 4.17 m.  A wavelength of antenna 1/4 long can couple to electromagnetic waves very effectively.  Y at - it wire in your system about 1 meter long?  USB cable? It is likely that you have some very nice antennas.  If the voltage from one of these antennas reached about 0.5 V, it will be sufficient to cause the internal diode junctions in any device of semiconductor (such as amplifiers, analog/digital converters and multiplexers) of lead.  This conduction is non-linear and produce a DC voltage out to the RF input.  This tension Gets the sum (with unknown polarity) with the signals you want to measure, prodcuing errors.

  What can you do about it?  Disable the transmitter will not solve the problem, but because it is needed for other purposes, is not an option.  The signals of interest being very low frequencies, it should be fairly easy to eliminate parasites.  Three general principles apply.  First is to eliminate the source, which has already been ruled out.  However, check if the transmitter power can be reduced without compromising the performance of the RF System. Second is to reduce the coupling.  If possible, keep the transmitting antenna as much as possible to the source of your slow signals and threads of connection to your data acquisition system. The orientation of the antenna and son can help too.  There are too many combinations to try even give general guidelines on this without more information on the physical configuration of your system.  Armor is a big part of the principle of coupling reduction and works well at 72 MHz.  All the sons of your signal sources for the acquisition of data and data acquisition to the computer must be shielded. Should be based on the shields.  Just make sure that you don't create ground loops in the process that can lead to other problems.  Connect everything to a pattern with a 'star' grounded to System.  The third principle is to reduce the signals interfere by filtering. I would try to put a ceramic capacitor of 100 nF for each signal line to the mass input on the DAQ hardware, keeping the capacitor leads as short as possible.  If your sources of signals have a very high impedance or inductive, you might have an EE assess suitable filtering.  The benefits of the capacitors are: cheap!, simple to install, will reduce RF interference over a wide bandwidth, require no development and are generally quite effective.

  The problems are depending on the severity, it can be quite simple eliminate your interference or it might require a major overhaul of the entire system.

  Lynn

  ADDRA Consulting, LLC

• Reading of analog signal using DAQPad-6016

  I'm reading an analog signal using DAQPad-6016.  An entry is on the ground, the other is Vdc.  I can't operate at MAX and I'm confused becaue MAX alone gives me an option for differential reading, but the list of pins give enough information on how to connect in a different way.  Is there a reference as well?

  Hello, Bernadette.

  This link should have what it takes to equip themselves properly: http://www.ni.com/gettingstarted/setuphardware/dataacquisition/analogvoltage.htm

  After that you have put work in place, specifically see step 11 for check the connections of the device.

  I hope this helps!

• How can I get digital signals (interface UART) with a microcontroller with NI USB-6008?

  I have acauired a few analog signals by A/D (3 channels). I put each scanned data on 3 digital output with a microcontroller. I want to see if it is possible to import these digital outputs 3 to a PC via a USB-6008? It's like the connection of the output to the digital input of the USB-6008 and import the 3 channels simultaneously to LabView? Do I need to use some other hardware like USB-8451 and connect the clock of the MCU to USB-8451?

  Saraydin,

  The digital I/o on the USB-6008 is a software program only, so unless your signals are rather slow, it probably will not work for you.  In general, the procedure would be to connect each signal to one of the digital lines on the map and then set up a digital entry into LabVIEW task to read the three channels.  If you use a device that has clocked by the digital i/o hardware, you then your input clock signal and use it as the sample for the task clock.  Here is a list of USB devices supporting DIO clocked by the hardware.  Also, there is an example that comes with LabVIEW, which shows how to do this.  You can get to it in LabVIEW by going to help > find examples.  When the example Finder window opens, navigate to hardware input and output > DAQmx > digital measures > Cont read dig Chan-Ext Clk.vi.

  The 8451 is specifically for I2C and SPI, and would be great if you try to make one of these protocols, but otherwise I would recommend the devices in the list I linked above.

  -Christina

• G20-120: how to choose digital airborne signal to Qosmioplayer?

  I have a G20-120 with analog/digital TV tuner.
  I now wish to leave the DVB - T tuner to receive airborne television signals. (Try mine with analog signals only)
  I can't find how? Any person who knows or who succeeded with that?

  MODIFIER

  Hello

  It would be very interesting to know what version of the Qosmio player you have.
  I found this official document to support Toshiba:
  http://support.toshiba-tro.de/KB0/TSB6101A90000R01.htm

  There, I found information that 4.3 Qosmio player and older Version does not support the DVB - T signal.
  The DVB - T signal can only be used in the Microsoft operating system

• How to measure how long a Boolean value is high with thick County?

  I acquire the impulse response of a parallax Distance sensor, but I I don't know how to measure the number of features that this signal is high (the time of the input signal is high is proportional to the distance). I would like to reset the counter thickness when this signal is low. is this possible? Y at - it another option?

  Thank you...

  for (imstuck) wrote:

  You will need to adjust some if you want an indicator of up-to-date at all times.

  Here is a very minimalist version which updates the timer continuously while the switch is on and holds last value when the switch is off. Try it!

  

• How to read 3 analog inputs simultaneously with 6070E?

  Hello

  I wanted to read 3 analog signals simultaneously using cards of acquiring data NI PXI-6070E and Labview 2010.

  I can with success read and record the 1 signal (which you can see in the attachment), but do not know and can not find examples on how to read 3 signals simultaneously. Any help, especially a simple example would be great.

  Thank you!

  Just click on = pull down from the constant physical channel, select Browse and shift-click or Ctl-click here to add other channels. You can also type in new channels with the ai0 syntax: 2 for three continuous channels for example.

• Help stairs analog signal

  Hi all

  I'm still new to LabVIEW, but I played a little enough to create a simple analog signal generator. Product signals appear staircased when displayed on an oscilloscope, but are smooth, when I read the signals in an entry (as shown by the graph on the waveform) analog. How can I change my program settings so that I can see this staircased signal?

  I run LabVIEW 2010 and use a data USB X Series multifunction acquisition.

  Thank you

  -Olivier