Sinusoidal Wave not Perfect

Thread Starter

Exjay

Joined Nov 19, 2015
166
Greetings to everyone,

I have passion to build my own function generator. So I surfed the web and found one circuit diagram at musicfromouterspace. The circuit and the generated sine wave is as attached. How can I get a full some wave from the circuit? Is there a faulty component somewhere in the circuit?
I sensed one of the diodes connected back to back is bad or am I wrong?
Please I need your suggestion.

Thanks for answering.
 

Attachments

MrChips

Joined Oct 2, 2009
30,714
XR8038, ICL8038, XR2206 function generator ICs are now discontinued.
If you search you may still be able to find one. I know I have some in stock.
 

Thread Starter

Exjay

Joined Nov 19, 2015
166
That circuit will not make a perfect sinewave. U1-A makes a triangle wave then U2-A simply squashes its peaks a little.
I made a perfect sinewave generator like this:
Dear Audio guru,
Thanks for your response.
They built this circuit on the website with a snapshot of the three wave forms there.
I got a perfect square and triangle wave but not a good sine wave.
I fined tune the three potentiometer and got a half wave sine wave.
I believed it will work since I got a perfect half sine wave but the remaining lower half are chopped off.
I think it needs troubleshooting.
Suggest please. I don't have much time and cash to buy new components.

Thanks looking forward to your response.
 

Thread Starter

Exjay

Joined Nov 19, 2015
166
XR8038, ICL8038, XR2206 function generator ICs are now discontinued.
If you search you may still be able to find one. I know I have some in stock.
Dear Mr Chip,

Thanks for your response.
I will consider that if someone can put me through the design process of the circuit.
I don't know if you can help me out with that.
Looking forward to hearing from you.
Thank you.
 

bertus

Joined Apr 5, 2008
22,270
Hello,

It looks like the sinus bias is off.
Is R24 the sinus bias potmeter correctly connected and adjusted?

Does the page where you found the schematic not show how to adjust the circuit?

Bertus
 

Thread Starter

Exjay

Joined Nov 19, 2015
166
Hello,

It looks like the sinus bias is off.
Is R24 the sinus bias potmeter correctly connected and adjusted?

Does the page where you found the schematic not show how to adjust the circuit?

Bertus
Dear Bertie,
Thanks for your response.
I have checked this R24, I found it was intact.
There is no section to get fine sine wave in the circuit website.

What can be the cause?

Please help me overcome this problem.
Looking forward to hearing from you.
 
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