Simple sine and square wawe generator

[robimarko]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

[grumpydoc]

http://images.lmgtfy.com/?q=simple+function+generator+that+can+generate+sine+and+square+wave

[benjamin545]

something like this?

http://www.amazon.com/Elenco-1MHz-Function-Generator-Kit/dp/B0002MQEW4/ref=sr_1_2?ie=UTF8&qid=1400620975&sr=8-2&keywords=elenco+function+generator

[robimarko]

I am more of DIY guy

[TVman]

I am more of DIY guy

I think it is A DIY kit.

[Bored@Work]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

So when you googled, which potential candidates (schematics, kits, products) did come up?

[Riotpack]

Maybe build something based on the old XR2206

www.jaycar.com.au/images_uploaded/xr2206v1.pdf

[robimarko]

Then I will have to order XR2206,I thought maybe there is one version that i can build with components that I have at home

[LvW]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

What does this mean? Sine and squarewave at the the same time ? Or alternating (selectable per swirch)? Which frequency? Tunable (this is most important)?
Why not using a simple RC oscillator (WIEN type or simlar) with additional limiting (clipping)?

[robimarko]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

What does this mean? Sine and squarewave at the the same time ? Or alternating (selectable per swirch)? Which frequency? Tunable (this is most important)?
Why not using a simple RC oscillator (WIEN type or simlar) with additional limiting (clipping)?

Of course not in the same time,selectable with swich.
Tunability is not so important.
I will try wien bridge oscillator

[LvW]

I will try wien bridge oscillator

Perhaps this choice can meet your requirements - perhaps not?
Do you have some particular requirements regarding frequency, amplitudes and quality of the signals?
These information are important for selection of a suitable principle.

[rdl]

You can build a rudimentary function generator from some op amps and a handful of resistors and capacitors. Try Googling "op amp function generator circuit"

[robimarko]

I have no special demands,only that signal is decent quality,5V amplitude would be perfect,as for frequency I have no specific demand,any frequency will be fine

Sent from my IOCEAN X7 using Tapatalk

[LvW]

Why not using a simple RC oscillator (WIEN type or simlar) with additional limiting (clipping)?

I think, I should better say ".....with an additional comparator".

[tszaboo]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

I need to chose a small resistor. Please help me.

We can only help if you can describe what you really want. Speed. Size. Peak to peak voltage. Price.
Give us at least some basic specification, otherwise we cannot help.

[robimarko]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

I need to chose a small resistor. Please help me.

We can only help if you can describe what you really want. Speed. Size. Peak to peak voltage. Price.
Give us at least some basic specification, otherwise we cannot help.

I need this generator for capacitance measurement with oscilloscope.
I think that 5V peak to peak will be fine and a frequency of 100kHz.
It would be great if price is around 10 dollars.

[jpb]

Why not just use a 555?

http://www.555-timer-circuits.com/simplest-555-oscillator.html

you can get the sin from the square wave with a low pass filter I guess.

[tszaboo]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

I need to chose a small resistor. Please help me.

We can only help if you can describe what you really want. Speed. Size. Peak to peak voltage. Price.
Give us at least some basic specification, otherwise we cannot help.

I need this generator for capacitance measurement with oscilloscope.
I think that 5V peak to peak will be fine and a frequency of 100kHz.
It would be great if price is around 10 dollars.

Very good! The 555 mentioned above is perfect for this application.
What I would do is the following: Make a 555 circuit, astable multivibrator, size it to around 100Hz-1Khz. It doesnt have to be 50%, close to it is fine. Power it from a 9V battery. That is cheap, easy, works untill the battery dies. Put a resistor on the output, or even better, a potentiometer, maybe even logaritmic pot.
Connect the ground and the output on the unknown capacitor. Measure the voltage across the capacitor with the scope.
Now, look at the scope plot. You will see the capacitor beeing charged throug the resistor, than discharged. At around 0% charge and 66% charge put the markers on the scope. The time between the two will be the theta, the time constant of the RC circuit. You can measure the R with a multimeter, and you can calculate the C. This is a very educational circuit, this is basically how I did it in high school (with analog scope because they rulez)

[robimarko]

Hi everybody,
I really need simple function generator that can generate sine and square wawe.
Please help me

I need to chose a small resistor. Please help me.

We can only help if you can describe what you really want. Speed. Size. Peak to peak voltage. Price.
Give us at least some basic specification, otherwise we cannot help.

I need this generator for capacitance measurement with oscilloscope.
I think that 5V peak to peak will be fine and a frequency of 100kHz.
It would be great if price is around 10 dollars.

Very good! The 555 mentioned above is perfect for this application.
What I would do is the following: Make a 555 circuit, astable multivibrator, size it to around 100Hz-1Khz. It doesnt have to be 50%, close to it is fine. Power it from a 9V battery. That is cheap, easy, works untill the battery dies. Put a resistor on the output, or even better, a potentiometer, maybe even logaritmic pot.
Connect the ground and the output on the unknown capacitor. Measure the voltage across the capacitor with the scope.
Now, look at the scope plot. You will see the capacitor beeing charged throug the resistor, than discharged. At around 0% charge and 66% charge put the markers on the scope. The time between the two will be the theta, the time constant of the RC circuit. You can measure the R with a multimeter, and you can calculate the C. This is a very educational circuit, this is basically how I did it in high school (with analog scope because they rulez)

Excellent idea,will definitively try it.
I will do this with analog scope.
Most definitively bang for a buck