The question i'm going to ask is that where is the feedback line in this amplifier and which is the resistor will determine the gain ?
I want to vary the gain for optimum performance, but couldn't find it.
Thanks in advance
I want to vary the gain for optimum performance, but couldn't find it.
Thanks in advance
R18 (2k7) is the feedback resistor. Bear in mind that altering feedback doesn't just vary the closed-loop gain, you will also change bandwidth and potentially affect stability.
Or is it R4 (1k). I'm not sure. Maybe both.
This circuit looks like it has had HF stability problems which have been patched up by sprinkling capacitors everywhere.
Or is it R4 (1k). I'm not sure. Maybe both.
This circuit looks like it has had HF stability problems which have been patched up by sprinkling capacitors everywhere.
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df96,
just to be sure, will it destroy my amp or lead to component failure ? or quality reduction ? (permanent changes, that can't be change even after i return to its original value.
Wanted to try to vary these values, see what will happen X.x
my friend said maybe R11 (2k2), and R10 (2k7), but just according to his feeling ^^
just to be sure, will it destroy my amp or lead to component failure ? or quality reduction ? (permanent changes, that can't be change even after i return to its original value.
Wanted to try to vary these values, see what will happen X.x
my friend said maybe R11 (2k2), and R10 (2k7), but just according to his feeling ^^
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😕what is the ||| you written meant for 😕
hm...... R5 ? seems unrelated ? (well.... i'm a beginner)
|| means in parallel. I think the answer may be ((R18||R4)/R5)+1, which means calculate the resistance of R18 and R4 in parallel, then divide by R5, then add 1.
Bear in mind that some resistors (possible R4?) have a DC bias effect as well as AC signal. This is quite a complicated circuit so I would not fiddle with it before understanding what each component does.
Bear in mind that some resistors (possible R4?) have a DC bias effect as well as AC signal. This is quite a complicated circuit so I would not fiddle with it before understanding what each component does.
hm.... the designer of this circuit had mentioned that R2,R12,VR2,VR12 is used to adjust bias and trim DC offset, so means those are not for bias ?
anyway, you mean parallel means by multiplying them ? or what should i do if i want to tweak the gain ?
Google "resistors in parallel". Almost any resistor in a circuit may have an effect on bias, which is why I suggest you understand the circuit before changing it.
hm..... i'm a beginner, so is there any link you could offer me to read about ? (all details about amplifier circuit ?
I don't know a good link for solid-state amp design. I learnt from years of thinking and reading books. I still regard myself as a beginner. Try books by Douglas Self, although they may start further on than you are at present.
There is one feedback loop consisting of R4 with compensating Cap C1, then there is another loop via R18. Because the whole amplifier is an inverting amplifier the feedback is summed and applied to the input. R18 also aids in the DC bias of transistor Q1, because of the DC component associated with it.
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