Hi All
So I modelled a simple CE amp in LTSpice (asc file attached) which indicated a gain in the input signal of about 4.5x.
I then breadboarded the exact same circuit (with an A50k pot on the output) and put a tone generator through it and only managed to achieve about 1.5x gain. Also tried a number of other transistors (PN100, BC549...) with the same result.
Note the transistor has a measured hfe of 354 (from a DMM with a transistor port), but the model in LTSpice is an unmodified BC547B (hfe about 295).
Is this discrepancy between modelled and real-world response normal? what can I do to push the signal amplification higher?
I've also attached my spreadsheet calculating the resistor requirements for biasing and capacitor selection - being very new to electronics, I'd be keen for some QA.
I'd be using these for audio circuitry - primarily guitar pedals, so input frequencies are likely to be between 30Hz-5kHz to allow for harmonics.
Thanks in advance!!
So I modelled a simple CE amp in LTSpice (asc file attached) which indicated a gain in the input signal of about 4.5x.
I then breadboarded the exact same circuit (with an A50k pot on the output) and put a tone generator through it and only managed to achieve about 1.5x gain. Also tried a number of other transistors (PN100, BC549...) with the same result.
Note the transistor has a measured hfe of 354 (from a DMM with a transistor port), but the model in LTSpice is an unmodified BC547B (hfe about 295).
Is this discrepancy between modelled and real-world response normal? what can I do to push the signal amplification higher?
I've also attached my spreadsheet calculating the resistor requirements for biasing and capacitor selection - being very new to electronics, I'd be keen for some QA.
I'd be using these for audio circuitry - primarily guitar pedals, so input frequencies are likely to be between 30Hz-5kHz to allow for harmonics.
Thanks in advance!!
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