English language is my weakness.
I know I am not saying anything new. I'm more devoted Vdif. My pattern was Walter Jung.
It is a pity that today, losing those who are interested in how that works.
Here it is together.
http://www.diyaudio.com/forums/digital-source/55422-barrie-gilberts-articles.html
http://www.diyaudio.com/forums/digital-source/55422-barrie-gilberts-articles.html
Thank you very much, I found the article here. The text is excellent. I see that much has already been explained. Barrie Gilbert states 18mV, it corresponds with my findings.
Thank you very much
No theory, but many years of experience. Vdif is warranted, as well as delays. Barrie Gilbert wrote a very interesting text. Now I know that my way is correct.
Vdif is dependent on the output voltage, gain and frequency. Gain and bandwidth of the input differential pair is dependent on the current.
According to Barrie Gilbert, a great cause Vdif distortion, in my opinion are increasing mutual modulation. Today, I confirmed that QQF 500kHz bandwidth is insufficient. Measured very many pieces, and all the same. No theory.
The topology HQQF not want to have fun. I did not tell the principal parameters. When the time comes, everything post. Let's please consider the possibility of an amplifier, according to the rotation of the output voltage.
Thank you
Barrie Gilbert, Are Op Amps Really Linear?
„If you have the patience to follow through with the rest of this analysis, you'll discover that the gain magnitude is different; that there is significant odd-harmonic distortion even at frequencies well below the unity-gain crossover; and that the phase angle is not only a function of frequency, but also of amplitude -- that is, the op amp generates a peculiar kind of amplitude-to-phase modulation, something which one should not expect of a linear system. But, then, an op amp is by no means as pristine in this respect as the textbooks suggest, and that gm cell has very strong open-loop distortion for even quite small inputs.
To anticipate our analysis, it is found that the third-harmonic distortion of a simple bipolar differential pair reaches 1% for a sinewave input amplitude of about 18 mV at 27ýC. Now, recall that the open-loop ac gain is only 1/, and consider what the nonlinear differential input (the error voltage V in Fig. 2) must be to provide a 10-V sinewave output at, say, one-hundredth of 1, we will find it to be a whopping 100 mV, much higher that the 1% voltage, and some 10% of the 1-V input at a gain of 10. Our question is, what will be actual differential error voltage be in practice, and the actual distortion? Finding the answers requires a bit more mathematics, with the device nonlinearities included.“
Barrie Gilbert addressed operational amplifier. I have dealt with the input differential pair of discrete amplifiers. The similarity is not coincidental. Barrie Gilbert also spoke about modulation.
„If you have the patience to follow through with the rest of this analysis, you'll discover that the gain magnitude is different; that there is significant odd-harmonic distortion even at frequencies well below the unity-gain crossover; and that the phase angle is not only a function of frequency, but also of amplitude -- that is, the op amp generates a peculiar kind of amplitude-to-phase modulation, something which one should not expect of a linear system. But, then, an op amp is by no means as pristine in this respect as the textbooks suggest, and that gm cell has very strong open-loop distortion for even quite small inputs.
To anticipate our analysis, it is found that the third-harmonic distortion of a simple bipolar differential pair reaches 1% for a sinewave input amplitude of about 18 mV at 27ýC. Now, recall that the open-loop ac gain is only 1/, and consider what the nonlinear differential input (the error voltage V in Fig. 2) must be to provide a 10-V sinewave output at, say, one-hundredth of 1, we will find it to be a whopping 100 mV, much higher that the 1% voltage, and some 10% of the 1-V input at a gain of 10. Our question is, what will be actual differential error voltage be in practice, and the actual distortion? Finding the answers requires a bit more mathematics, with the device nonlinearities included.“
An externally hosted image should be here but it was not working when we last tested it.
Barrie Gilbert addressed operational amplifier. I have dealt with the input differential pair of discrete amplifiers. The similarity is not coincidental. Barrie Gilbert also spoke about modulation.
I see that you still not understand that this is a real measurement. A few years ago the fiber with 1209 posts. This thread is about something else, so I will not repeat over and over. If you are interested in QQF, here is the thread.
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