- #26

NascentOxygen

Staff Emeritus

Science Advisor

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How did it get to be too small? It is supposed to have been » R3 all along.I increased R_{L}to 13.08K and now it's a lot closer to 4V_{p}.

Yes, and that is what the design procedure achieves (with most of the parameters given to you in the problem specifications).But I am a little confused. Shouldn't each value be able to be calculated in order to reach the requirement of an 8V peak-to-peak output.

That can be taken into account, too, when calculating AC gain.In the end the only real assumption was the value of R_{load}which I just made really large.

If you need to adjust gain to a precise value, you have no choice but to set the value by experiment. The model is only approximate, and you haven't measured Q1's beta.I haven't finished finding the values of the capacitors yet though. But if I don't come to exactly 8V_{pp}symmetrical output then I would have had to gone wrong somewhere. (and just adding a resistor and experimentally finding a value that works is wrong)

Refer to the procedure I outlined earlier. (If in doubt, make then x10 larger.)And what is the formula for finding the capacitor values?

You now have to sweep the frequency over the range of interest, to make sure the gain extends over the full specified bandwidth.