Electronics > Beginners
TL071 distortion - bad amplifier design?
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spec:

--- Quote from: perieanuo on December 10, 2018, 10:55:06 am ---And for god's sake put limiting resistors on base on final resistors, once they saturate you're in trouble.
On input I will use in your place bigger capacitors like 10 uF


Envoyé de mon iPad en utilisant Tapatalk

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The output transistors are fine. But it is quite true, that in common with many audio amplifiers, that this amplifier is not short circuit protected
spec:

--- Quote from: AngraMelo on December 10, 2018, 04:39:06 pm ---Well, on the scope, the crossover distortion was clear. There were bumps on the side of the waves near the 0V line. I guess lowering the 220R resistor would help bring it to the "AB" side.

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The bumps 'on the sides' are crossover distortion. If you can see them on the scope, it is gross distortion.
The amplifier as it stands is essentially class B, not class AB.

On the schematic that you originally posted there is a missing dot connection between the two 0.22R resistors. Is this a typo and is that connection actually made in practice?

Did you try changing the capacitors as I suggested in reply #21?
AngraMelo:
It is a typo. The resistors are connected to the output.
Im trying your suggestin right now. Ill be back in a moment
spec:

--- Quote from: AngraMelo on December 10, 2018, 07:54:03 pm ---It is a typo. The resistors are connected to the output.
Im trying your suggestin right now. Ill be back in a moment

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Thanks

Attached below is the mod for converting the amplifier from deep class B to class AB. Set Iq to 30mA to 40mA. Physically place the flat part of the BC337 case in contact with one of the driver transistor cases.
AngraMelo:
Thank you so much!!!! Im about to try it!!!

I just soldered the 2 47uf capacitors.
Should I keep them on your desing? Or I go back to the 4.7nf?
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