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Generate and acquire signals from Walkie Talkies

Hello, i am a Portuguese Student and i have some problems in a Academic Project.

 

The following project consists in two Walkie Talkies that are link to a USB 6009.

One of the Walkie talkies are attached do AO0 and ground with the objective of generate a signal to the 6009 then the other Walkie talkie connected to Ai0 and GND have to acquire the same signal that i generate in the other one, this two signals have the main problem that needs to be represented in the same Chart or Graf.

 

Please can anyone help me in this question and send me a (vi), i would greatly appreciate.

something send me a post or email for l21739@gmai.com.

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@juhu wrote:

Hello, i am a Portuguese Student and i have some problems in a Academic Project.

 

Please can anyone help me in this question and send me a (vi), i would greatly appreciate.

something send me a post or email for l21739@gmai.com.


Shall I write the report for you alsoSmiley Very Happy

Why do you not show us what you have done so far. And tell us why and how you struggle. We are happy to help in this forum. But we are not some free homework service. You have to put in some effort your self. By the way I do not think a 6009 unit is the best choice for such a project. Since analog out function is quite limited. How about using the sound card



Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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To expand on what Coq Rouge wrote: The reason the USB-6009 is a poor choice for your application is that the analog outputs are software timed with a maximum update rate of less than 150 Hz.  When you include the Nyquist limit, you could not send any signal with a frequency above 75 Hz and you would need to be much lower if you want a nice, near-sinusoidal signal.  By then you would be below the low frequency limit for the audio passband of your walkie talkie.

 

Lynn

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I have some ideas for using a sound card. If your Teacher says it is OK to use a sound card.



Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
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hello thanks for the post.

So far i have acquire the signals from the input signal, but it came with noise and others.

The main problem is the output signal that i simulate (sine wave), does not arrive to the other Walkie Talkie (receiver).

The project is connect an Walkie Takie (A) to a extensometer ( to measured strain) and another Wakie Talkie (B) to the USB 6009 ( is the only hardware in the lab that i have). When the Walkie Talkie (A) measured some strain the Wakie Talkie (B) have to receive the strain in (cm ISO).

So far i can´t do anything else than the acquire signal, i think that the USB 6009 is not the more indicated but is the only one that i have.

I will send the graph in jpg for you to see, but the only thing that i want for now, and i can be able to do it is send and receive signals in the same graph or chart.

can anyone help me please

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Your strain is probably a low frequency signal which could not directly modulate the walkie talkie anyway.  In that case once you got past the simulation to real data the system still would not work.

 

I recommend that you do several things:

1. Determine the magnitude and frequency of the signals you ultimately want to measure.  Also determine the required resolution and accuracy.  Estimate the signal to noise ratio at the transducer. ---  All these things affect every other decision you will make about the project, so do this first.  If you have to estimate or approximate some of these values, be sure to document that they are estimates so they can be validated or adjusted later.

2. If you want to test the receiving end and the noise introduced by the transmission channel, use a signal generator (set to the values from 1.) to modulate the transmitting walkie talkie.

3. Consider building a circuit which will take your strain signal and create an audio frequency signal you can feed to the walkie talkie audio input.  Look up voltage to frequency converters.

 

Lynn

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Hello Lynn,

 

Sorry about the late response, but only today i have access again to the USB 6009 in the LAB.

In below are the graph from the input signal, the first is the graph from the Walkie Talkie (receiver) when the button from the Walkie Talkie that send the signal are not press. What we see is only noise and others frequency's.

In the other graph we can see a different graph this graph is from the  Walkie Talkie (receiver) but when the button from the Walkie Talkie that send the signal are press where we can see that is a different kind of signal and the receiver are ready to receive the signal and are receiving some signal from the other walkie talkie.

 

First I need some help for this first steps

1- But how can I generate a signal wave and send it from the other Walkie Talkie (transmitter), I used a Basic Function Generator

 

2-How can I see in  the Walkie Talkie (receiver) if he receive the Signal that I generate in the transmitter, The graph changes of frequency and amplitude always that I press the button of the transmitter Walkie Talkie.

 

3-How can I put the two signals in the same chart or graph, The main problem is like you said the USB 6009 is too low sending signals.

 

Sorry my English, I appreciate any help

Thanks 

BTP

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Here is an example to solve your third question. Merging two or more signals into one graph:

Block Diagram.pngFront Panel.PNG

 

Block diagram                                                                                                                                Front panel

Regards,
Even
_________________________________
Certified LabVIEW Associate Developer

Automated Test Developer
Topro AS
Norway
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The signal displayed while the other transmitter is running looks like it has a strong 100 Hz component.  Is this twice the power line frequency? This may indicate a problem with the way your receiver and data acquisition device are grounded.  Also, the Data acquisition device (or the receiver) may be overloaded if the transmitting walkie talkie is too close to the receiver and computer.

 

Q1. You cannot generate a suitable signal with your USB-6009.  You need to build some kind of audio frequency generator in external circuitry.  If you use a voltage to frequency converter or a voltage controlled oscillator, you could change the frequency of the audio tone by changing the DC voltage from the Analog Output of the USB-6009.

Q2. Have you tired whistling or humming a tune into the transmitter microphone?  This usually generates a fairly clean modulating signal.  Then you need to listen to the receiver and see if what you detect with the USB-6009 and the software seem similar to the whistle.  An oscilloscope is helpful if you have one available.  That gives you an independent means of verifying that the signal is there.

Q3. Even Deejay gave you one answer.  Look at the Help files for the graph.  They tell you how to connect multiple signals.  If you have been using LV for less than 30 years, it is a good idea to always keep the Context Help window open while programming.

 

Lynn

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