It's the tenth printing, dated January 1955.
There are no addenda at the back. It ends with the final Chapter XIX "Illustrative Designs for Single Loop Feedback Amplifiers"
Very sorry I can't help you, Dave.
I don't promote anything here as this is just my hobby, but I want to learn more and I don't have good explanation about this difference between CFA and VFA Bode plots. I think what I did with TMC in my VFA is quite close to the maximum and that one was built and working for years. The ULGF of my CFA is not 40 MHz but 4.5 MHz only.
I hope Richard Marsh will give more information, he is testing and measuring this amp.
Apparently not, if I get comments like that.
If you are under the impression that all those amplifiers worked and keep working because of luck, I think you misunderstand the process of engineering for quantity manufacture. Come on. let's not be rude to each other.
I thought it was established beyond any doubt that 0R1 gives lower crossover distortion than higher values. It also reduces losses in the output stage, especially for sub-8R loads. What's not to like?
Thank you for the courtesy.
Best wishes
David
If anyone else has a later version of Bode I would love to know.
You've used two pole compensation and you have high loop gains in your CFA. You can easily get the same shape with a VFA Damir.
Yes, I can use local VAS feedback to lower LF loop gain, but as I said already I can't get loop gain of 80 dB at 20 kHz, and with this CFA it comes so natural.
If you look at Dadod's graph and draw a line at about 26dB gain and look at the loop gain at 20KHz, the loop gain is over 50dB. If you look at MiiB's VFA plot at 26dB you have less than 30dB. There goes to show CFA has much higher loop gain at 20KHz than VFA even though MiiB's VFA has higher loop gain at lower frequency.
It is the -3dB of the open loop gain that matters. dadod's CFA has -3dB slightly above 20KHz, but MiiB's VFA has -3dB below 50Hz. All the high open loop gain means nothing if the open loop gain start rolling off too early.
If you compare loop gain at 1KHz, CFA here still beat the VFA by about 20dB.
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Those graphs are loop gain not open loop gain, you don't need to subtract anything.
You never explain why 0.1ohm works reliably. I love to hear it. Did you just do it and it works OR do you have a theoretical explanation? Reputation is not a proof of your assertion, you are going to need more to explain this.
No offense, I can't really read your book and take it too seriously. You gave a lot of assertions, but you don't explain why. This is science, not magic, you make big assertion like this, you are going to have to do better than just say "I design for this and that companies and it works".
So far, your so called Class B is pretty much Class AB with Oliver's condition that you don't give credit to. From your Table 10.2, you pretty much followed Oliver's condition. You have about 30mV across Re IF everything is matched and perfect. If you have an offset of 5 to 10mV if you don't match hfe and/or Vbe, you will have 10 to 20% difference in current and the one that has 20% more current will heat up more and get hotter, in turn reducing the Vbe and further increase the current and go into current hogging.
That's the reason I am matching hfe and Vbe before I attempt to lower to 0.12ohm EVEN you claim that it is safe to use 0.1ohm. I am going to start out with 0.22ohm, measure the voltage across all the Re. If I see over 3mV difference, I won't even attempt lowering to 0.12ohm.
So please explain your assertion if you have one.
Sorry
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OK, but my rationing still hold,
But the advantage of your is less because MiiB's VFA still have about 40dB of loop gain. At some point of time when loop gain is over 40, it really does not matter as much.
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A remarkable synthesis of almost all the of common errors, confusions and misunderstandings regarding the amplifier's loop gain. Please do your homework by reading the fundamentals, to many to quote on your Google friend.
