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design simple amp
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NASK:
i need to understand basic bjt amplifier concept therefor I design this simple amp but i didn't getting required out put using calculation values. could i know reason for it?  (i have attached the calculation & out puts)
furthermore, using Cin & Cout calculated value didn't come to at least near to the required output  value. but change it to Cin 10uF and Cout 15uF it pass the 1V peak but not come to 2V peak (design value) .Is it not possible to achieve Av=200 from Bc548
oPossum:
2N2222 has much lower Hfe than BC548
Zero999:
Use lower resistor values for the biasing potential divider, if possible, so the Hfe is less of a factor.
Kleinstein:
For AC the R5 is effectively parallel to R1 and thus the gain is reduced.
LvW:
Without any external load - and assuming that all capacitors are large enough for coupling the 1kHz - the actual gain is Av=-6k/25=-240.
Because I do not see that the load is specified, the remaining task is to find the proper load resistor for reducing the gain to -200.
That is a simple task.
In case, the load is given the effective gain determining resistor is 6k||10k=3.75 kohms and the gain can never reach the value of -200.
(Av=-3.75k/25=-150) .
Comment: Modifying the base resistors cannot help at all because it is the transconductance (gm=1/re) that matters only (as far as gain is concerned).
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