Hi..
I am trying to build a stereo amp based on 2*ta8210 chips.
I check the noise while my ears is very close to the speakers)
And I have an hiss background noise that increases with volume pot movement..The noise exist even zero volume..Source is connected or not result is same..
So I tried a few things.
Nothing connected to amplifier inputs!!..
I also have 1nF bypass cap close&connected to the input pin of the chip and goes to gnd..
1-I shunt input rca + & -
Noise is fix(independent pot movement) and decreased..
2-I connect input cap shield(electrolitic cap) to gnd.
Noise is fix(independent pot movement) and decreased..
3-I connect positive side of input cap(leg goes to input pin of the chip) to gnd.
Zero noise..Dead quite..
Does this mean that input cap picking rfi??
I use cheap input cap..
How can I remove the noise completely?
If you have any experience similar to mine, can you share it with me?
Or do you have any guess/suggestion for me?
I am trying to build a stereo amp based on 2*ta8210 chips.
I check the noise while my ears is very close to the speakers)
And I have an hiss background noise that increases with volume pot movement..The noise exist even zero volume..Source is connected or not result is same..
So I tried a few things.
Nothing connected to amplifier inputs!!..
I also have 1nF bypass cap close&connected to the input pin of the chip and goes to gnd..
1-I shunt input rca + & -
Noise is fix(independent pot movement) and decreased..
2-I connect input cap shield(electrolitic cap) to gnd.
Noise is fix(independent pot movement) and decreased..
3-I connect positive side of input cap(leg goes to input pin of the chip) to gnd.
Zero noise..Dead quite..
Does this mean that input cap picking rfi??
I use cheap input cap..
How can I remove the noise completely?
If you have any experience similar to mine, can you share it with me?
Or do you have any guess/suggestion for me?
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How can I remove the noise completely?
Can you post photos of the pcb and wiring?
Can you post photos of the pcb and wiring?
Attachments
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It sounds like noise being picked up by the unshielded/untwisted input wires.1-I shunt input rca + & -
Noise is fix(independent pot movement) and decreased..
Short out the input capacitor
I tried it now and Dead quite!!
What does this mean??
I tried it now and Dead quite!!
What does this mean??
This looks like a single supply amplifier circuit, so the input blocking capacitor is necessary.
Does the amplifier still work when you short the input capacitor, which blocks DC and protects the source?
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Can you post a picture showing what you've done?
I connect +&- of the input cap.
Did you mean this?
Attachments
This looks like a single supply amplifier circuit, so the input blocking capacitor is necessary.
Does the amplifier still work when you short the input capacitor?
I didn't connect it to source when I shorted the +&- of the input cap.Probably it can damage to the speakers..
I didn't connect it to source when I shorted the +&- of the input cap.
Probably it can damage to the speakers.
That could also damage your signal source, as well as cause the amplifier to malfunction.
If the source has its own blocking capacitor maybe not, but it depends on the details.
The noise could be high frequency oscillation.
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Ah, that probably explains why it's silent with the capacitor shortedThis looks like a single supply amplifier circuit
Remove the short and see if it still works
Ah, that probably explains why it's silent with the capacitor shorted
Remove the short and see if it still works
Oh you think input caps are extra
Yeah it still works..
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