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3 Copy edited (e.g. ref. <https://en.wiktionary.org/wiki/op-amp#English>, <<http://english.stackexchange.com/questions/15953>>, and <https://en.wiktionary.org/wiki/basicly>).
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Op Amp-amp circuit has lower gain onat low frequencies

I'm trying to design an amplifier, which amplifies line level audio to 5Vpp5 Vpp, so I can sample it with a microcontrolermicrocontroller. My plan is to do this in two steps: amplify the signal to 5Vpp5 Vpp and then add a 2.5V5 V offset. I'm stuck at the first step.

I put together a simple inverting amplifier like so:
  

Op Amp Circuit
Op Amp 

I'm using isthe LM324N op-amp. I'm powering it using a PC Powerpower supply  (-12V12 V for negative rail, 12V and 12 V for positive rail). Ground, pictured in the circuit is 0V0 V.

I'm testing the setup with sina sine wave  (from my phone) as input. AmplifierThe amplifier works normally at higher frequencies, but the gain starts dropping at around 300Hz300 Hz. At 20Hz20 Hz, the gain is basiclybasically 1. For example:

1000Hz1000 Hz:
Normal at 1000Hz

40Hz:
Lower Gain at 40HzNormal at 1000 Hz

So, my question is40 Hz:

Lower gain at 40 Hz

What am I doing wrong? Is this normal behaviour for this Op Ampop-amp? As I understand, Op Ampsop-amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?

Op Amp lower gain on low frequencies

I'm trying to design an amplifier, which amplifies line level audio to 5Vpp, so I can sample it with a microcontroler. My plan is to do this in two steps: amplify the signal to 5Vpp and then add 2.5V offset. I'm stuck at the first step.

I put together a simple inverting amplifier like so:
 Op Amp Circuit
Op Amp I'm using is LM324N. I'm powering it using PC Power supply(-12V for negative rail, 12V for positive rail). Ground, pictured in the circuit is 0V.

I'm testing the setup with sin wave(from my phone) as input. Amplifier works normally at higher frequencies, but gain starts dropping at around 300Hz. At 20Hz, gain is basicly 1. For example:

1000Hz:
Normal at 1000Hz

40Hz:
Lower Gain at 40Hz

So, my question is: What am I doing wrong? Is this normal behaviour for this Op Amp? As I understand, Op Amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?

Op-amp circuit has lower gain at low frequencies

I'm trying to design an amplifier, which amplifies line level audio to 5 Vpp, so I can sample it with a microcontroller. My plan is to do this in two steps: amplify the signal to 5 Vpp and then add a 2.5 V offset. I'm stuck at the first step.

I put together a simple inverting amplifier like so: 

Op Amp Circuit 

I'm using the LM324N op-amp. I'm powering it using a PC power supply  (-12 V for negative rail and 12 V for positive rail). Ground, pictured in the circuit is 0 V.

I'm testing the setup with a sine wave  (from my phone) as input. The amplifier works normally at higher frequencies, but the gain starts dropping at around 300 Hz. At 20 Hz, the gain is basically 1. For example:

1000 Hz:

Normal at 1000 Hz

40 Hz:

Lower gain at 40 Hz

What am I doing wrong? Is this normal behaviour for this op-amp? As I understand, op-amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?

2 deleted 4 characters in body
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I'm trying to design an amplifier, which amplifies line level audio to 5Vpp, so I can sample it with a microcontroler. My plan is to do this in two steps: amplify the signal to 5Vpp and then add 2.5V offset. I'm stuck at the first step.

I put together a simple non inverting amplifier like so:
Op Amp Circuit
Op Amp I'm using is LM324N. I'm powering it using PC Power supply(-12V for negative rail, 12V for positive rail). Ground, pictured in the circuit is 0V.

I'm testing the setup with sin wave(from my phone) as input. Amplifier works normally at higher frequencies, but gain starts dropping at around 300Hz. At 20Hz, gain is basicly 1. For example:

1000Hz:
Normal at 1000Hz

40Hz:
Lower Gain at 40Hz

So, my question is: What am I doing wrong? Is this normal behaviour for this Op Amp? As I understand, Op Amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?

I'm trying to design an amplifier, which amplifies line level audio to 5Vpp, so I can sample it with a microcontroler. My plan is to do this in two steps: amplify the signal to 5Vpp and then add 2.5V offset. I'm stuck at the first step.

I put together a simple non inverting amplifier like so:
Op Amp Circuit
Op Amp I'm using is LM324N. I'm powering it using PC Power supply(-12V for negative rail, 12V for positive rail). Ground, pictured in the circuit is 0V.

I'm testing the setup with sin wave(from my phone) as input. Amplifier works normally at higher frequencies, but gain starts dropping at around 300Hz. At 20Hz, gain is basicly 1. For example:

1000Hz:
Normal at 1000Hz

40Hz:
Lower Gain at 40Hz

So, my question is: What am I doing wrong? Is this normal behaviour for this Op Amp? As I understand, Op Amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?

I'm trying to design an amplifier, which amplifies line level audio to 5Vpp, so I can sample it with a microcontroler. My plan is to do this in two steps: amplify the signal to 5Vpp and then add 2.5V offset. I'm stuck at the first step.

I put together a simple inverting amplifier like so:
Op Amp Circuit
Op Amp I'm using is LM324N. I'm powering it using PC Power supply(-12V for negative rail, 12V for positive rail). Ground, pictured in the circuit is 0V.

I'm testing the setup with sin wave(from my phone) as input. Amplifier works normally at higher frequencies, but gain starts dropping at around 300Hz. At 20Hz, gain is basicly 1. For example:

1000Hz:
Normal at 1000Hz

40Hz:
Lower Gain at 40Hz

So, my question is: What am I doing wrong? Is this normal behaviour for this Op Amp? As I understand, Op Amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?

1
source | link

Op Amp lower gain on low frequencies

I'm trying to design an amplifier, which amplifies line level audio to 5Vpp, so I can sample it with a microcontroler. My plan is to do this in two steps: amplify the signal to 5Vpp and then add 2.5V offset. I'm stuck at the first step.

I put together a simple non inverting amplifier like so:
Op Amp Circuit
Op Amp I'm using is LM324N. I'm powering it using PC Power supply(-12V for negative rail, 12V for positive rail). Ground, pictured in the circuit is 0V.

I'm testing the setup with sin wave(from my phone) as input. Amplifier works normally at higher frequencies, but gain starts dropping at around 300Hz. At 20Hz, gain is basicly 1. For example:

1000Hz:
Normal at 1000Hz

40Hz:
Lower Gain at 40Hz

So, my question is: What am I doing wrong? Is this normal behaviour for this Op Amp? As I understand, Op Amps start behaving abnormally at high frequencies, not at low. Is something wrong with my input?