its not that i dont believe you,but you see the difference.....cant be software's fault....
i use multisim v11
bjt version
opamp version
i use multisim v11
bjt version
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opamp version
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Multisim is a piece of crud software, i hate it!!
LT switchercad is so much better!. Even circuitmaker is better than multisim.
Multisim is intended for school electronics teaching.
LT switchercad is so much better!. Even circuitmaker is better than multisim.
Multisim is intended for school electronics teaching.
Try with 100R for R8 instead 1k, and 22R for R10 instead 220R, and use 2k2 for R12...
with this setup response was very well but with something pV at output...
i leaved the R12 at 2.2k and i played with values of R8 & R10 because there seems to be the problem....
the better response i got so far is with R10=5k & R8=100R....
FLow(-3db)=1.6Hz
Fhigh(-3db)=9Khz
still far from the best....
An externally hosted image should be here but it was not working when we last tested it.
BD243/BD244 work with voltage gain x5 (R8/R10), with 5k for R10 there is no enough gain. Try remove C11...
This is my very old amp (see post #99), there is no any files, but no need for new pcb design, just copy from old pcb.
hmm..ok seems that ac analysis in this circuit cant work well or something else dont know..
i changed frequency manually from source and i got same output for all the bandwidth....🙂 i was like WTF 😕...
i changed frequency manually from source and i got same output for all the bandwidth....🙂 i was like WTF 😕...
Never trust simulation! I've had things not work at all in simulation that have worked perfectly fine in reality and vice versa.
I differ... I have had things simulate well in multisim but lockup LTspice. The operators knowledge doing the simulation , the simulator itself ,and the models used will determine the accuracy of the simulation. I just had LT predict my OPS bias point within 1mv from the simulation to the real thing. I knew almost exactly where to set the trimmer to get my 70ma VBias beforehand, no guessing .
I have also simulated classic designs and the simulator predicted the bandwidth and THD within a few % of the OEM specifications ... again, I had to use accurate models that matched the OEM's specs.
OS
Actually is not that multisim doing wrong but its difficult to understand its mind and how it calculate some things...
if i find time i will seperate the schematic into stages and i will see which stage doing this low-pass filter response....
i have already tested the opamp stage and i got clear response...
if i find time i will seperate the schematic into stages and i will see which stage doing this low-pass filter response....
i have already tested the opamp stage and i got clear response...
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