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circuit to measure flow

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kushal.khanal

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I am having problem in finding velocity or flow of liquid

I have already amplified the received signal but since the sine wave detected is being clipped ;How can I measure the time period of frequency shifted signal;

Can someone suggest some pulse shaping circuitry to square wave or any other solutions?

Waiting desperately for helpful minds.....

Thank you
 

A.Anand Srinivasan

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Re: circuit to measure flow of liquid using ultrasound

use a comparator with one input grounded i.e. a zero crossing detector to convert the sine wave to square wave....
 

kushal.khanal

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A.Anand Srinivasan said:
use a comparator with one input grounded i.e. a zero crossing detector to convert the sine wave to square wave....


FIRST OF ALL,
THANKS A LOT FOR LENDING HELPING HANDS.

I THINK I COULD NOT MAKE YOU UNDERSTAND GUYS!!!

AS SHOWN IN FIG BELOW I HAVE CLIPPED SINE WAVE AND I HAVE TO CONVERT IT TO SQUARE WAVE FOR COUNTING ITS FREQUENCY.

ANY IDEA GUYS??????@?!

TO:A.Anand Srinivasan &IanP

WHEN I MAKE ONE INPUT GROUND OF COMPARATOR OPAMP;THIS MEANS REF VOLTAGE IS 0V;
AND MAKE INPUT TO THE OTHER END THE CLIPPED SINE WAVE (SEE BELOW)
WILL I GET SQUARE WAVES WITHOUT EXTRA CIRCUITRY???




------
* *
* *
* * .
* * .
---*-----------*------------*---------
. * *
. * *
* *
*------*
PK-PK (6-8)V

FIG:CILPPED SINE WAVE PULSE TO BE SHAPED TO SQUARE WAVE




. . 5V
* * * * * * *
* * *
* * *
* * *
---*----------* * * * * * * ----------------------------0V
.
.



FIG: SQAURE WAVE TO BE OBTAINED




AND IanP

CAN YOU SUGGEST A SPECIFIC CONFIGURATION OF SCHMITT TRIGGER LOOKING ABOVE;
AS I TRIED SCHMITT TRIGGER BUT IN VAIN;

WAITING... EAGERLY
THANK YOU
 

A.Anand Srinivasan

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Re: circuit to measure flow of liquid using ultrasound

dude post your waveform and the waveform you got when you used a schmitt trigger so that we can understand better...
 

IanP

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Re: circuit to measure flow of liquid using ultrasound

It would be good idea to "MERGE" both your posts, so there is a complete picture on what you intend to do in one place .. Maybe you should ask moderators to do that ..
Anyhow, below is "modified" version of sin-to-square converter, this one has theshold adjustment and 1/2Vcc reference (not 0V) ..
Instead of typical comparator such as the LM339 you can use any general purpose (single rail) opamp, for example the LM358 ..

Regards,
IanP
 

kushal.khanal

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Re: circuit to measure flow of liquid using ultrasound

uh la la!!!!!!!

i thought making waveforms withs symbols were better but they were distorted.
so i have posted an attachment of schmitt trigger used with waveforms input and output and what is to be obtained.

so would you again look this guys;
its embarrasing to ask ask again and again something but......what to do?


Regards
kushal khanal
 

A.Anand Srinivasan

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Re: circuit to measure flow of liquid using ultrasound

that circuit would work just fine... provided you know the voltage you are setting using the divider and the amount of hysteresis you are providing is aptly what you need.....
 

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